🔖 Version 2.1.2.1

Fixes regression from #24302

.devcontainer/Dockerfile

@@ -0,0 +1,29 @@
+# See here for image contents: https://github.com/microsoft/vscode-dev-containers/tree/v0.187.0/containers/python-3/.devcontainer/base.Dockerfile
+
+# [Choice] Python version: 3, 3.9, 3.8, 3.7, 3.6
+ARG VARIANT="3.9.0-buster"
+FROM python:${VARIANT}
+
+# [Option] Install Node.js
+ARG INSTALL_NODE="true"
+ARG NODE_VERSION="lts/*"
+RUN if [ "${INSTALL_NODE}" = "true" ]; then su vscode -c "umask 0002 && . /usr/local/share/nvm/nvm.sh && nvm install ${NODE_VERSION} 2>&1"; fi
+
+# [Optional] If your pip requirements rarely change, uncomment this section to add them to the image.
+# COPY requirements.txt /tmp/pip-tmp/
+# RUN pip3 --disable-pip-version-check --no-cache-dir install -r /tmp/pip-tmp/requirements.txt \
+#    && rm -rf /tmp/pip-tmp
+
+# [Optional] Uncomment this section to install additional OS packages.
+# RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
+#     && apt-get -y install --no-install-recommends <your-package-list-here>
+
+# [Optional] Uncomment this line to install global node packages.
+# RUN su vscode -c "source /usr/local/share/nvm/nvm.sh && npm install -g <your-package-here>" 2>&1
+
+
+RUN pip install -U https://github.com/platformio/platformio-core/archive/develop.zip
+RUN platformio update
+# To get the test platforms
+RUN pip install PyYaml
+#ENV PATH /code/buildroot/bin/:/code/buildroot/tests/:${PATH}

.devcontainer/devcontainer.json

@@ -0,0 +1,51 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the README at:
+// https://github.com/microsoft/vscode-dev-containers/tree/v0.187.0/containers/python-3
+{
+  "name": "Python 3",
+  "build": {
+    "dockerfile": "Dockerfile",
+    "context": "..",
+    "args": {
+      // Update 'VARIANT' to pick a Python version: 3, 3.6, 3.7, 3.8, 3.9
+      "VARIANT": "3.9.0-buster",
+      // Options
+      "INSTALL_NODE": "false",
+      "NODE_VERSION": "lts/*"
+    }
+  },
+
+  // Set *default* container specific settings.json values on container create.
+  "settings": {
+    "python.pythonPath": "/usr/local/bin/python",
+    "python.languageServer": "Pylance",
+    "python.linting.enabled": true,
+    "python.linting.pylintEnabled": true,
+    "python.formatting.autopep8Path": "/usr/local/py-utils/bin/autopep8",
+    "python.formatting.blackPath": "/usr/local/py-utils/bin/black",
+    "python.formatting.yapfPath": "/usr/local/py-utils/bin/yapf",
+    "python.linting.banditPath": "/usr/local/py-utils/bin/bandit",
+    "python.linting.flake8Path": "/usr/local/py-utils/bin/flake8",
+    "python.linting.mypyPath": "/usr/local/py-utils/bin/mypy",
+    "python.linting.pycodestylePath": "/usr/local/py-utils/bin/pycodestyle",
+    "python.linting.pydocstylePath": "/usr/local/py-utils/bin/pydocstyle",
+    "python.linting.pylintPath": "/usr/local/py-utils/bin/pylint"
+  },
+
+  // Add the IDs of extensions you want installed when the container is created.
+  "extensions": [
+    "ms-python.python",
+    "ms-python.vscode-pylance",
+    "platformio.platformio-ide",
+    "marlinfirmware.auto-build",
+    "editorconfig.editorconfig"
+  ],
+
+  // Use 'forwardPorts' to make a list of ports inside the container available locally.
+  // "forwardPorts": [],
+
+  // Use 'postCreateCommand' to run commands after the container is created.
+  // "postCreateCommand": "pip3 install --user -r requirements.txt",
+
+  // Comment out connect as root instead. More info: https://aka.ms/vscode-remote/containers/non-root.
+  // "remoteUser": "vscode"
+}

.editorconfig

@@ -14,6 +14,10 @@ end_of_line = lf
 indent_style = space
 indent_size = 2
 
-[{*.py,*.conf,*.sublime-project}]
+[{*.py}]
+indent_style = space
+indent_size = 4
+
+[{*.conf,*.sublime-project}]
 indent_style = tab
 indent_size = 4

.github/contributing.md

@@ -34,8 +34,11 @@ This project and everyone participating in it is governed by the [Marlin Code of
 
 We have a Message Board and a Facebook group where our knowledgable user community can provide helpful advice if you have questions.
 
-* [Marlin RepRap forum](https://reprap.org/forum/list.php?415)
-* [MarlinFirmware on Facebook](https://www.facebook.com/groups/1049718498464482/)
+- [Marlin Documentation](https://marlinfw.org) - Official Marlin documentation
+- Facebook Group ["Marlin Firmware"](https://www.facebook.com/groups/1049718498464482/)
+- RepRap.org [Marlin Forum](https://forums.reprap.org/list.php?415)
+- Facebook Group ["Marlin Firmware for 3D Printers"](https://www.facebook.com/groups/3Dtechtalk/)
+- [Marlin Configuration](https://www.youtube.com/results?search_query=marlin+configuration) on YouTube
 
 If chat is more your speed, you can join the MarlinFirmware Discord server:
 
@@ -116,7 +119,7 @@ Unsure where to begin contributing to Marlin? You can start by looking through t
 
 ### Pull Requests
 
-Pull Requests should always be targeted to working branches (e.g., `bugfix-2.0.x` and/or `bugfix-1.1.x`) and never to release branches (e.g., `2.0.x` and/or `1.1.x`). If this is your first Pull Request, please read our [Guide to Pull Requests](https://marlinfw.org/docs/development/getting_started_pull_requests.html) and Github's [Pull Request](https://help.github.com/articles/creating-a-pull-request/) documentation.
+Pull Requests should always be targeted to working branches (e.g., `bugfix-2.1.x` and/or `bugfix-1.1.x`) and never to release branches (e.g., `2.0.x` and/or `1.1.x`). If this is your first Pull Request, please read our [Guide to Pull Requests](https://marlinfw.org/docs/development/getting_started_pull_requests.html) and Github's [Pull Request](https://help.github.com/articles/creating-a-pull-request/) documentation.
 
 * Fill in [the required template](pull_request_template.md).
 * Don't include issue numbers in the PR title.

.gitignore

@@ -21,35 +21,18 @@
 
 # Generated files
 _Version.h
-bdf2u8g
+bdf2u8g.exe
+genpages.exe
 marlin_config.json
 mczip.h
 *.gen
 *.sublime-workspace
 
-#
 # OS
-#
 applet/
 .DS_Store
 
-#
-# Misc
-#
-*~
-*.orig
-*.rej
-*.bak
-*.idea
-*.i
-*.ii
-*.swp
-tags
-
-#
-# C++
-#
-# Compiled Object files
+# Compiled C++ Object files
 *.slo
 *.lo
 *.o
@@ -80,10 +63,7 @@ tags
 *.out
 *.app
 
-#
-# C
-#
-# Object files
+# Compiled C Object files
 *.o
 *.ko
 *.obj
@@ -143,12 +123,13 @@ vc-fileutils.settings
 .vscode/*
 !.vscode/extensions.json
 
-#Simulation
+# Simulation files
 imgui.ini
 eeprom.dat
 spi_flash.bin
+fs.img
 
-#cmake
+# CMake
 CMakeLists.txt
 src/CMakeLists.txt
 CMakeListsPrivate.txt
@@ -169,3 +150,16 @@ __pycache__
 
 # IOLogger logs
 *_log.csv
+
+# Misc.
+*~
+*.orig
+*.rej
+*.bak
+*.idea
+*.i
+*.ii
+*.swp
+tags
+*.logs
+*.bak

Makefile

@@ -1,11 +1,16 @@
+SCRIPTS_DIR := buildroot/share/scripts
+CONTAINER_RT_BIN := docker
+CONTAINER_RT_OPTS := --rm -v $(PWD):/code -v platformio-cache:/root/.platformio
+CONTAINER_IMAGE := marlin-dev
+
 help:
 	@echo "Tasks for local development:"
 	@echo "* tests-single-ci:             Run a single test from inside the CI"
 	@echo "* tests-single-local:          Run a single test locally"
-	@echo "* tests-single-local-docker:   Run a single test locally, using docker-compose"
+	@echo "* tests-single-local-docker:   Run a single test locally, using docker"
 	@echo "* tests-all-local:             Run all tests locally"
-	@echo "* tests-all-local-docker:      Run all tests locally, using docker-compose"
-	@echo "* setup-local-docker:          Setup local docker-compose"
+	@echo "* tests-all-local-docker:      Run all tests locally, using docker"
+	@echo "* setup-local-docker:          Build the local docker image"
 	@echo ""
 	@echo "Options for testing:"
 	@echo "  TEST_TARGET          Set when running tests-single-*, to select the"
@@ -27,26 +32,28 @@ tests-single-ci:
 
 tests-single-local:
 	@if ! test -n "$(TEST_TARGET)" ; then echo "***ERROR*** Set TEST_TARGET=<your-module> or use make tests-all-local" ; return 1; fi
-	export PATH=./buildroot/bin/:./buildroot/tests/:${PATH} \
+	export PATH="./buildroot/bin/:./buildroot/tests/:${PATH}" \
 	  && export VERBOSE_PLATFORMIO=$(VERBOSE_PLATFORMIO) \
 	  && run_tests . $(TEST_TARGET) "$(ONLY_TEST)"
 .PHONY: tests-single-local
 
 tests-single-local-docker:
 	@if ! test -n "$(TEST_TARGET)" ; then echo "***ERROR*** Set TEST_TARGET=<your-module> or use make tests-all-local-docker" ; return 1; fi
-	docker-compose run --rm marlin $(MAKE) tests-single-local TEST_TARGET=$(TEST_TARGET) VERBOSE_PLATFORMIO=$(VERBOSE_PLATFORMIO) GIT_RESET_HARD=$(GIT_RESET_HARD) ONLY_TEST="$(ONLY_TEST)"
+	@if ! $(CONTAINER_RT_BIN) images -q $(CONTAINER_IMAGE) > /dev/null ; then $(MAKE) setup-local-docker ; fi
+	$(CONTAINER_RT_BIN) run $(CONTAINER_RT_OPTS) $(CONTAINER_IMAGE) $(MAKE) tests-single-local TEST_TARGET=$(TEST_TARGET) VERBOSE_PLATFORMIO=$(VERBOSE_PLATFORMIO) GIT_RESET_HARD=$(GIT_RESET_HARD) ONLY_TEST="$(ONLY_TEST)"
 .PHONY: tests-single-local-docker
 
 tests-all-local:
-	export PATH=./buildroot/bin/:./buildroot/tests/:${PATH} \
+	export PATH="./buildroot/bin/:./buildroot/tests/:${PATH}" \
 	  && export VERBOSE_PLATFORMIO=$(VERBOSE_PLATFORMIO) \
-	  && for TEST_TARGET in $$(./get_test_targets.py) ; do echo "Running tests for $$TEST_TARGET" ; run_tests . $$TEST_TARGET ; done
+	  && for TEST_TARGET in $$($(SCRIPTS_DIR)/get_test_targets.py) ; do echo "Running tests for $$TEST_TARGET" ; run_tests . $$TEST_TARGET ; done
 .PHONY: tests-all-local
 
 tests-all-local-docker:
-	docker-compose run --rm marlin $(MAKE) tests-all-local VERBOSE_PLATFORMIO=$(VERBOSE_PLATFORMIO) GIT_RESET_HARD=$(GIT_RESET_HARD)
+	@if ! $(CONTAINER_RT_BIN) images -q $(CONTAINER_IMAGE) > /dev/null ; then $(MAKE) setup-local-docker ; fi
+	$(CONTAINER_RT_BIN) run $(CONTAINER_RT_OPTS) $(CONTAINER_IMAGE) $(MAKE) tests-all-local VERBOSE_PLATFORMIO=$(VERBOSE_PLATFORMIO) GIT_RESET_HARD=$(GIT_RESET_HARD)
 .PHONY: tests-all-local-docker
 
 setup-local-docker:
-	docker-compose build
+	$(CONTAINER_RT_BIN) build -t $(CONTAINER_IMAGE) -f docker/Dockerfile .
 .PHONY: setup-local-docker

Marlin/Makefile

@@ -109,7 +109,7 @@ LIQUID_TWI2        ?= 0
 # This defines if Wire is needed
 WIRE               ?= 0
 
-# This defines if Tone is needed (i.e SPEAKER is defined in Configuration.h)
+# This defines if Tone is needed (i.e., SPEAKER is defined in Configuration.h)
 # Disabling this (and SPEAKER) saves approximately 350 bytes of memory.
 TONE               ?= 1
 
@@ -307,133 +307,22 @@ else ifeq ($(HARDWARE_MOTHERBOARD),1154)
 else ifeq ($(HARDWARE_MOTHERBOARD),1155)
 # Tenlog D3 Hero IDEX printer
 else ifeq ($(HARDWARE_MOTHERBOARD),1156)
-# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend0, Hotend1, Fan, Bed)
+# Tenlog D3,5,6 Pro IDEX printers
 else ifeq ($(HARDWARE_MOTHERBOARD),1157)
-# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend0, Hotend1, Hotend2, Bed)
+# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend0, Hotend1, Fan, Bed)
 else ifeq ($(HARDWARE_MOTHERBOARD),1158)
-# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend, Fan0, Fan1, Bed)
+# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend0, Hotend1, Hotend2, Bed)
 else ifeq ($(HARDWARE_MOTHERBOARD),1159)
-# Longer LK1 PRO / Alfawise U20 Pro (PRO version)
+# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend, Fan0, Fan1, Bed)
 else ifeq ($(HARDWARE_MOTHERBOARD),1160)
-# Longer LKx PRO / Alfawise Uxx Pro (PRO version)
+# Longer LK1 PRO / Alfawise U20 Pro (PRO version)
 else ifeq ($(HARDWARE_MOTHERBOARD),1161)
-
-
-# 3Drag Controller
-else ifeq ($(HARDWARE_MOTHERBOARD),1100)
-# Velleman K8200 Controller (derived from 3Drag Controller)
-else ifeq ($(HARDWARE_MOTHERBOARD),1101)
-# Velleman K8400 Controller (derived from 3Drag Controller)
-else ifeq ($(HARDWARE_MOTHERBOARD),1102)
-# Velleman K8600 Controller (Vertex Nano)
-else ifeq ($(HARDWARE_MOTHERBOARD),1103)
-# Velleman K8800 Controller (Vertex Delta)
-else ifeq ($(HARDWARE_MOTHERBOARD),1104)
-# 2PrintBeta BAM&DICE with STK drivers
-else ifeq ($(HARDWARE_MOTHERBOARD),1105)
-# 2PrintBeta BAM&DICE Due with STK drivers
-else ifeq ($(HARDWARE_MOTHERBOARD),1106)
-# MKS BASE v1.0
-else ifeq ($(HARDWARE_MOTHERBOARD),1107)
-# MKS v1.4 with A4982 stepper drivers
-else ifeq ($(HARDWARE_MOTHERBOARD),1108)
-# MKS v1.5 with Allegro A4982 stepper drivers
-else ifeq ($(HARDWARE_MOTHERBOARD),1109)
-# MKS v1.6 with Allegro A4982 stepper drivers
-else ifeq ($(HARDWARE_MOTHERBOARD),1110)
-# MKS BASE 1.0 with Heroic HR4982 stepper drivers
-else ifeq ($(HARDWARE_MOTHERBOARD),1111)
-# MKS GEN v1.3 or 1.4
-else ifeq ($(HARDWARE_MOTHERBOARD),1112)
-# MKS GEN L
-else ifeq ($(HARDWARE_MOTHERBOARD),1113)
-# zrib V2.0 control board (Chinese RAMPS replica)
-else ifeq ($(HARDWARE_MOTHERBOARD),1114)
-# BigTreeTech or BIQU KFB2.0
-else ifeq ($(HARDWARE_MOTHERBOARD),1115)
-# Felix 2.0+ Electronics Board (RAMPS like)
-else ifeq ($(HARDWARE_MOTHERBOARD),1116)
-# Invent-A-Part RigidBoard
-else ifeq ($(HARDWARE_MOTHERBOARD),1117)
-# Invent-A-Part RigidBoard V2
-else ifeq ($(HARDWARE_MOTHERBOARD),1118)
-# Sainsmart 2-in-1 board
-else ifeq ($(HARDWARE_MOTHERBOARD),1119)
-# Ultimaker
-else ifeq ($(HARDWARE_MOTHERBOARD),1120)
-# Ultimaker (Older electronics. Pre 1.5.4. This is rare)
-else ifeq ($(HARDWARE_MOTHERBOARD),1121)
-  MCU              ?= atmega1280
-  PROG_MCU         ?= m1280
-
-# Azteeg X3
-else ifeq ($(HARDWARE_MOTHERBOARD),1122)
-# Azteeg X3 Pro
-else ifeq ($(HARDWARE_MOTHERBOARD),1123)
-# Ultimainboard 2.x (Uses TEMP_SENSOR 20)
-else ifeq ($(HARDWARE_MOTHERBOARD),1124)
-# Rumba
-else ifeq ($(HARDWARE_MOTHERBOARD),1125)
-# Raise3D Rumba
-else ifeq ($(HARDWARE_MOTHERBOARD),1126)
-# Rapide Lite RL200 Rumba
-else ifeq ($(HARDWARE_MOTHERBOARD),1127)
-# Formbot T-Rex 2 Plus
-else ifeq ($(HARDWARE_MOTHERBOARD),1128)
-# Formbot T-Rex 3
-else ifeq ($(HARDWARE_MOTHERBOARD),1129)
-# Formbot Raptor
-else ifeq ($(HARDWARE_MOTHERBOARD),1130)
-# Formbot Raptor 2
-else ifeq ($(HARDWARE_MOTHERBOARD),1131)
-# bq ZUM Mega 3D
-else ifeq ($(HARDWARE_MOTHERBOARD),1132)
-# MakeBoard Mini v2.1.2 is a control board sold by MicroMake
-else ifeq ($(HARDWARE_MOTHERBOARD),1133)
-# TriGorilla Anycubic version 1.3 based on RAMPS EFB
-else ifeq ($(HARDWARE_MOTHERBOARD),1134)
-# TriGorilla Anycubic version 1.4 based on RAMPS EFB
-else ifeq ($(HARDWARE_MOTHERBOARD),1135)
-# TriGorilla Anycubic version 1.4 Rev 1.1
-else ifeq ($(HARDWARE_MOTHERBOARD),1136)
-# Creality: Ender-4, CR-8
-else ifeq ($(HARDWARE_MOTHERBOARD),1137)
-# Creality: CR10S, CR20, CR-X
-else ifeq ($(HARDWARE_MOTHERBOARD),1138)
-# Dagoma F5
-else ifeq ($(HARDWARE_MOTHERBOARD),1139)
-# FYSETC F6 1.3
-else ifeq ($(HARDWARE_MOTHERBOARD),1140)
-# FYSETC F6 1.5
-else ifeq ($(HARDWARE_MOTHERBOARD),1141)
-# Duplicator i3 Plus
-else ifeq ($(HARDWARE_MOTHERBOARD),1142)
-# VORON
-else ifeq ($(HARDWARE_MOTHERBOARD),1143)
-# TRONXY V3 1.0
-else ifeq ($(HARDWARE_MOTHERBOARD),1144)
-# Z-Bolt X Series
-else ifeq ($(HARDWARE_MOTHERBOARD),1145)
-# TT OSCAR
-else ifeq ($(HARDWARE_MOTHERBOARD),1146)
-# Overlord/Overlord Pro
-else ifeq ($(HARDWARE_MOTHERBOARD),1147)
-# ADIMLab Gantry v1
-else ifeq ($(HARDWARE_MOTHERBOARD),1148)
-# ADIMLab Gantry v2
-else ifeq ($(HARDWARE_MOTHERBOARD),1149)
-# BIQU Tango V1
-else ifeq ($(HARDWARE_MOTHERBOARD),1150)
-# MKS GEN L V2
-else ifeq ($(HARDWARE_MOTHERBOARD),1151)
-# MKS GEN L V2.1
-else ifeq ($(HARDWARE_MOTHERBOARD),1152)
-# Copymaster 3D
-else ifeq ($(HARDWARE_MOTHERBOARD),1153)
-# Ortur 4
-else ifeq ($(HARDWARE_MOTHERBOARD),1154)
-# Tenlog D3 Hero
-else ifeq ($(HARDWARE_MOTHERBOARD),1155)
+# Longer LKx PRO / Alfawise Uxx Pro (PRO version)
+else ifeq ($(HARDWARE_MOTHERBOARD),1162)
+# Zonestar zrib V5.3 (Chinese RAMPS replica)
+else ifeq ($(HARDWARE_MOTHERBOARD),1163)
+# Pxmalion Core I3
+else ifeq ($(HARDWARE_MOTHERBOARD),1164)
 
 #
 # RAMBo and derivatives

Marlin/Version.h

@@ -28,7 +28,7 @@
 /**
  * Marlin release version identifier
  */
-//#define SHORT_BUILD_VERSION "2.0.9.4"
+//#define SHORT_BUILD_VERSION "2.1.2.1"
 
 /**
  * Verbose version identifier which should contain a reference to the location
@@ -41,7 +41,7 @@
  * here we define this default string as the date where the latest release
  * version was tagged.
  */
-//#define STRING_DISTRIBUTION_DATE "2022-06-04"
+//#define STRING_DISTRIBUTION_DATE "2023-05-16"
 
 /**
  * Defines a generic printer name to be output to the LCD after booting Marlin.

Marlin/config.ini

@@ -0,0 +1,211 @@
+#
+# Marlin Firmware
+# config.ini - Options to apply before the build
+#
+[config:base]
+ini_use_config                           = none
+
+# Load all config: sections in this file
+;ini_use_config                          = all
+# Load config file relative to Marlin/
+;ini_use_config                          = another.ini
+# Download configurations from GitHub
+;ini_use_config                          = example/Creality/Ender-5 Plus @ bugfix-2.1.x
+# Download configurations from your server
+;ini_use_config                          = https://me.myserver.com/path/to/configs
+# Evaluate config:base and do a config dump
+;ini_use_config                          = base
+;config_export                           = 2
+
+[config:minimal]
+motherboard                              = BOARD_RAMPS_14_EFB
+serial_port                              = 0
+baudrate                                 = 250000
+
+use_watchdog                             = on
+thermal_protection_hotends               = on
+thermal_protection_hysteresis            = 4
+thermal_protection_period                = 40
+
+bufsize                                  = 4
+block_buffer_size                        = 16
+max_cmd_size                             = 96
+
+extruders                                = 1
+temp_sensor_0                            = 1
+
+temp_hysteresis                          = 3
+heater_0_mintemp                         = 5
+heater_0_maxtemp                         = 275
+preheat_1_temp_hotend                    = 180
+
+bang_max                                 = 255
+pidtemp                                  = on
+pid_k1                                   = 0.95
+pid_max                                  = BANG_MAX
+pid_functional_range                     = 10
+
+default_kp                               = 22.20
+default_ki                               = 1.08
+default_kd                               = 114.00
+
+x_driver_type                            = A4988
+y_driver_type                            = A4988
+z_driver_type                            = A4988
+e0_driver_type                           = A4988
+
+x_bed_size                               = 200
+x_min_pos                                = 0
+x_max_pos                                = X_BED_SIZE
+
+y_bed_size                               = 200
+y_min_pos                                = 0
+y_max_pos                                = Y_BED_SIZE
+
+z_min_pos                                = 0
+z_max_pos                                = 200
+
+x_home_dir                               = -1
+y_home_dir                               = -1
+z_home_dir                               = -1
+
+use_xmin_plug                            = on
+use_ymin_plug                            = on
+use_zmin_plug                            = on
+
+x_min_endstop_inverting                  = false
+y_min_endstop_inverting                  = false
+z_min_endstop_inverting                  = false
+
+default_axis_steps_per_unit              = { 80, 80, 400, 500 }
+axis_relative_modes                      = { false, false, false, false }
+default_max_feedrate                     = { 300, 300, 5, 25 }
+default_max_acceleration                 = { 3000, 3000, 100, 10000 }
+
+homing_feedrate_mm_m                     = { (50*60), (50*60), (4*60) }
+homing_bump_divisor                      = { 2, 2, 4 }
+
+x_enable_on                              = 0
+y_enable_on                              = 0
+z_enable_on                              = 0
+e_enable_on                              = 0
+
+invert_x_dir                             = false
+invert_y_dir                             = true
+invert_z_dir                             = false
+invert_e0_dir                            = false
+
+invert_e_step_pin                        = false
+invert_x_step_pin                        = false
+invert_y_step_pin                        = false
+invert_z_step_pin                        = false
+
+disable_x                                = false
+disable_y                                = false
+disable_z                                = false
+disable_e                                = false
+
+proportional_font_ratio                  = 1.0
+default_nominal_filament_dia             = 1.75
+
+junction_deviation_mm                    = 0.013
+
+default_acceleration                     = 3000
+default_travel_acceleration              = 3000
+default_retract_acceleration             = 3000
+
+default_minimumfeedrate                  = 0.0
+default_mintravelfeedrate                = 0.0
+
+minimum_planner_speed                    = 0.05
+min_steps_per_segment                    = 6
+default_minsegmenttime                   = 20000
+
+[config:basic]
+bed_overshoot                            = 10
+busy_while_heating                       = on
+default_ejerk                            = 5.0
+default_keepalive_interval               = 2
+default_leveling_fade_height             = 0.0
+disable_inactive_extruder                = on
+display_charset_hd44780                  = JAPANESE
+eeprom_boot_silent                       = on
+eeprom_chitchat                          = on
+endstoppullups                           = on
+extrude_maxlength                        = 200
+extrude_mintemp                          = 170
+host_keepalive_feature                   = on
+hotend_overshoot                         = 15
+jd_handle_small_segments                 = on
+lcd_info_screen_style                    = 0
+lcd_language                             = en
+max_bed_power                            = 255
+mesh_inset                               = 0
+min_software_endstops                    = on
+max_software_endstops                    = on
+min_software_endstop_x                   = on
+min_software_endstop_y                   = on
+min_software_endstop_z                   = on
+max_software_endstop_x                   = on
+max_software_endstop_y                   = on
+max_software_endstop_z                   = on
+preheat_1_fan_speed                      = 0
+preheat_1_label                          = "PLA"
+preheat_1_temp_bed                       = 70
+prevent_cold_extrusion                   = on
+prevent_lengthy_extrude                  = on
+printjob_timer_autostart                 = on
+probing_margin                           = 10
+show_bootscreen                          = on
+soft_pwm_scale                           = 0
+string_config_h_author                   = "(none, default config)"
+temp_bed_hysteresis                      = 3
+temp_bed_residency_time                  = 10
+temp_bed_window                          = 1
+temp_residency_time                      = 10
+temp_window                              = 1
+validate_homing_endstops                 = on
+xy_probe_feedrate                        = (133*60)
+z_clearance_between_probes               = 5
+z_clearance_deploy_probe                 = 10
+z_clearance_multi_probe                  = 5
+
+[config:advanced]
+arc_support                              = on
+auto_report_temperatures                 = on
+autotemp                                 = on
+autotemp_oldweight                       = 0.98
+bed_check_interval                       = 5000
+default_stepper_deactive_time            = 120
+default_volumetric_extruder_limit        = 0.00
+disable_inactive_e                       = true
+disable_inactive_x                       = true
+disable_inactive_y                       = true
+disable_inactive_z                       = true
+e0_auto_fan_pin                          = -1
+encoder_100x_steps_per_sec               = 80
+encoder_10x_steps_per_sec                = 30
+encoder_rate_multiplier                  = on
+extended_capabilities_report             = on
+extruder_auto_fan_speed                  = 255
+extruder_auto_fan_temperature            = 50
+fanmux0_pin                              = -1
+fanmux1_pin                              = -1
+fanmux2_pin                              = -1
+faster_gcode_parser                      = on
+homing_bump_mm                           = { 5, 5, 2 }
+max_arc_segment_mm                       = 1.0
+min_arc_segment_mm                       = 0.1
+min_circle_segments                      = 72
+n_arc_correction                         = 25
+serial_overrun_protection                = on
+slowdown                                 = on
+slowdown_divisor                         = 2
+temp_sensor_bed                          = 0
+thermal_protection_bed_hysteresis        = 2
+thermocouple_max_errors                  = 15
+tx_buffer_size                           = 0
+watch_bed_temp_increase                  = 2
+watch_bed_temp_period                    = 60
+watch_temp_increase                      = 2
+watch_temp_period                        = 20

Marlin/src/HAL/AVR/HAL.h

@@ -19,6 +19,10 @@
  */
 #pragma once
 
+/**
+ * HAL for Arduino AVR
+ */
+
 #include "../shared/Marduino.h"
 #include "../shared/HAL_SPI.h"
 #include "fastio.h"
@@ -28,6 +32,7 @@
   #include <HardwareSerial.h>
 #else
   #include "MarlinSerial.h"
+  #define BOARD_NO_NATIVE_USB
 #endif
 
 #include <stdint.h>
@@ -102,36 +107,36 @@ typedef Servo hal_servo_t;
 
   #define MYSERIAL1 TERN(BLUETOOTH, btSerial, MSerial0)
 #else
-  #if !WITHIN(SERIAL_PORT, -1, 3)
-    #error "SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
+  #if !WITHIN(SERIAL_PORT, 0, 3)
+    #error "SERIAL_PORT must be from 0 to 3."
   #endif
   #define MYSERIAL1 customizedSerial1
 
   #ifdef SERIAL_PORT_2
-    #if !WITHIN(SERIAL_PORT_2, -1, 3)
-      #error "SERIAL_PORT_2 must be from 0 to 3, or -1 for USB Serial."
+    #if !WITHIN(SERIAL_PORT_2, 0, 3)
+      #error "SERIAL_PORT_2 must be from 0 to 3."
     #endif
     #define MYSERIAL2 customizedSerial2
   #endif
 
   #ifdef SERIAL_PORT_3
-    #if !WITHIN(SERIAL_PORT_3, -1, 3)
-      #error "SERIAL_PORT_3 must be from 0 to 3, or -1 for USB Serial."
+    #if !WITHIN(SERIAL_PORT_3, 0, 3)
+      #error "SERIAL_PORT_3 must be from 0 to 3."
     #endif
     #define MYSERIAL3 customizedSerial3
   #endif
 #endif
 
 #ifdef MMU2_SERIAL_PORT
-  #if !WITHIN(MMU2_SERIAL_PORT, -1, 3)
-    #error "MMU2_SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
+  #if !WITHIN(MMU2_SERIAL_PORT, 0, 3)
+    #error "MMU2_SERIAL_PORT must be from 0 to 3"
   #endif
   #define MMU2_SERIAL mmuSerial
 #endif
 
 #ifdef LCD_SERIAL_PORT
-  #if !WITHIN(LCD_SERIAL_PORT, -1, 3)
-    #error "LCD_SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
+  #if !WITHIN(LCD_SERIAL_PORT, 0, 3)
+    #error "LCD_SERIAL_PORT must be from 0 to 3."
   #endif
   #define LCD_SERIAL lcdSerial
   #if HAS_DGUS_LCD

Marlin/src/HAL/AVR/Servo.cpp

@@ -66,27 +66,26 @@ static volatile int8_t Channel[_Nbr_16timers];              // counter for the s
 
 /************ static functions common to all instances ***********************/
 
-static inline void handle_interrupts(timer16_Sequence_t timer, volatile uint16_t* TCNTn, volatile uint16_t* OCRnA) {
-  if (Channel[timer] < 0)
-    *TCNTn = 0; // channel set to -1 indicated that refresh interval completed so reset the timer
-  else {
-    if (SERVO_INDEX(timer, Channel[timer]) < ServoCount && SERVO(timer, Channel[timer]).Pin.isActive)
-      extDigitalWrite(SERVO(timer, Channel[timer]).Pin.nbr, LOW); // pulse this channel low if activated
-  }
+static inline void handle_interrupts(const timer16_Sequence_t timer, volatile uint16_t* TCNTn, volatile uint16_t* OCRnA) {
+  int8_t cho = Channel[timer];                                        // Handle the prior Channel[timer] first
+  if (cho < 0)                                                        // Channel -1 indicates the refresh interval completed...
+    *TCNTn = 0;                                                       // ...so reset the timer
+  else if (SERVO_INDEX(timer, cho) < ServoCount)                      // prior channel handled?
+    extDigitalWrite(SERVO(timer, cho).Pin.nbr, LOW);                  // pulse the prior channel LOW
 
-  Channel[timer]++;    // increment to the next channel
-  if (SERVO_INDEX(timer, Channel[timer]) < ServoCount && Channel[timer] < SERVOS_PER_TIMER) {
-    *OCRnA = *TCNTn + SERVO(timer, Channel[timer]).ticks;
-    if (SERVO(timer, Channel[timer]).Pin.isActive)    // check if activated
-      extDigitalWrite(SERVO(timer, Channel[timer]).Pin.nbr, HIGH); // it's an active channel so pulse it high
+  Channel[timer] = ++cho;                                             // Handle the next channel (or 0)
+  if (cho < SERVOS_PER_TIMER && SERVO_INDEX(timer, cho) < ServoCount) {
+    *OCRnA = *TCNTn + SERVO(timer, cho).ticks;                        // set compare to current ticks plus duration
+    if (SERVO(timer, cho).Pin.isActive)                               // activated?
+      extDigitalWrite(SERVO(timer, cho).Pin.nbr, HIGH);               // yes: pulse HIGH
   }
   else {
     // finished all channels so wait for the refresh period to expire before starting over
-    if (((unsigned)*TCNTn) + 4 < usToTicks(REFRESH_INTERVAL))    // allow a few ticks to ensure the next OCR1A not missed
-      *OCRnA = (unsigned int)usToTicks(REFRESH_INTERVAL);
-    else
-      *OCRnA = *TCNTn + 4;  // at least REFRESH_INTERVAL has elapsed
-    Channel[timer] = -1; // this will get incremented at the end of the refresh period to start again at the first channel
+    const unsigned int cval = ((unsigned)*TCNTn) + 32 / (SERVO_TIMER_PRESCALER), // allow 32 cycles to ensure the next OCR1A not missed
+                       ival = (unsigned int)usToTicks(REFRESH_INTERVAL); // at least REFRESH_INTERVAL has elapsed
+    *OCRnA = max(cval, ival);
+
+    Channel[timer] = -1;                                              // reset the timer counter to 0 on the next call
   }
 }
 
@@ -123,91 +122,102 @@ static inline void handle_interrupts(timer16_Sequence_t timer, volatile uint16_t
 
 /****************** end of static functions ******************************/
 
-void initISR(timer16_Sequence_t timer) {
-  #ifdef _useTimer1
-    if (timer == _timer1) {
-      TCCR1A = 0;             // normal counting mode
-      TCCR1B = _BV(CS11);     // set prescaler of 8
-      TCNT1 = 0;              // clear the timer count
-      #if defined(__AVR_ATmega8__) || defined(__AVR_ATmega128__)
-        SBI(TIFR, OCF1A);      // clear any pending interrupts;
-        SBI(TIMSK, OCIE1A);    // enable the output compare interrupt
-      #else
-        // here if not ATmega8 or ATmega128
-        SBI(TIFR1, OCF1A);     // clear any pending interrupts;
-        SBI(TIMSK1, OCIE1A);   // enable the output compare interrupt
-      #endif
-      #ifdef WIRING
-        timerAttach(TIMER1OUTCOMPAREA_INT, Timer1Service);
-      #endif
-    }
-  #endif
+void initISR(const timer16_Sequence_t timer_index) {
+  switch (timer_index) {
+    default: break;
 
-  #ifdef _useTimer3
-    if (timer == _timer3) {
-      TCCR3A = 0;             // normal counting mode
-      TCCR3B = _BV(CS31);     // set prescaler of 8
-      TCNT3 = 0;              // clear the timer count
-      #ifdef __AVR_ATmega128__
-        SBI(TIFR, OCF3A);     // clear any pending interrupts;
-        SBI(ETIMSK, OCIE3A);  // enable the output compare interrupt
-      #else
-        SBI(TIFR3, OCF3A);   // clear any pending interrupts;
-        SBI(TIMSK3, OCIE3A); // enable the output compare interrupt
-      #endif
-      #ifdef WIRING
-        timerAttach(TIMER3OUTCOMPAREA_INT, Timer3Service);  // for Wiring platform only
-      #endif
-    }
-  #endif
+    #ifdef _useTimer1
+      case _timer1:
+        TCCR1A = 0;             // normal counting mode
+        TCCR1B = _BV(CS11);     // set prescaler of 8
+        TCNT1 = 0;              // clear the timer count
+        #if defined(__AVR_ATmega8__) || defined(__AVR_ATmega128__)
+          SBI(TIFR, OCF1A);      // clear any pending interrupts;
+          SBI(TIMSK, OCIE1A);    // enable the output compare interrupt
+        #else
+          // here if not ATmega8 or ATmega128
+          SBI(TIFR1, OCF1A);     // clear any pending interrupts;
+          SBI(TIMSK1, OCIE1A);   // enable the output compare interrupt
+        #endif
+        #ifdef WIRING
+          timerAttach(TIMER1OUTCOMPAREA_INT, Timer1Service);
+        #endif
+        break;
+    #endif
 
-  #ifdef _useTimer4
-    if (timer == _timer4) {
-      TCCR4A = 0;             // normal counting mode
-      TCCR4B = _BV(CS41);     // set prescaler of 8
-      TCNT4 = 0;              // clear the timer count
-      TIFR4 = _BV(OCF4A);     // clear any pending interrupts;
-      TIMSK4 = _BV(OCIE4A);   // enable the output compare interrupt
-    }
-  #endif
+    #ifdef _useTimer3
+      case _timer3:
+        TCCR3A = 0;             // normal counting mode
+        TCCR3B = _BV(CS31);     // set prescaler of 8
+        TCNT3 = 0;              // clear the timer count
+        #ifdef __AVR_ATmega128__
+          SBI(TIFR, OCF3A);     // clear any pending interrupts;
+          SBI(ETIMSK, OCIE3A);  // enable the output compare interrupt
+        #else
+          SBI(TIFR3, OCF3A);   // clear any pending interrupts;
+          SBI(TIMSK3, OCIE3A); // enable the output compare interrupt
+        #endif
+        #ifdef WIRING
+          timerAttach(TIMER3OUTCOMPAREA_INT, Timer3Service);  // for Wiring platform only
+        #endif
+        break;
+    #endif
 
-  #ifdef _useTimer5
-    if (timer == _timer5) {
-      TCCR5A = 0;             // normal counting mode
-      TCCR5B = _BV(CS51);     // set prescaler of 8
-      TCNT5 = 0;              // clear the timer count
-      TIFR5 = _BV(OCF5A);     // clear any pending interrupts;
-      TIMSK5 = _BV(OCIE5A);   // enable the output compare interrupt
-    }
-  #endif
+    #ifdef _useTimer4
+      case _timer4:
+        TCCR4A = 0;             // normal counting mode
+        TCCR4B = _BV(CS41);     // set prescaler of 8
+        TCNT4 = 0;              // clear the timer count
+        TIFR4 = _BV(OCF4A);     // clear any pending interrupts;
+        TIMSK4 = _BV(OCIE4A);   // enable the output compare interrupt
+        break;
+    #endif
+
+    #ifdef _useTimer5
+      case _timer5:
+        TCCR5A = 0;             // normal counting mode
+        TCCR5B = _BV(CS51);     // set prescaler of 8
+        TCNT5 = 0;              // clear the timer count
+        TIFR5 = _BV(OCF5A);     // clear any pending interrupts;
+        TIMSK5 = _BV(OCIE5A);   // enable the output compare interrupt
+        break;
+    #endif
+  }
 }
 
-void finISR(timer16_Sequence_t timer) {
+void finISR(const timer16_Sequence_t timer_index) {
   // Disable use of the given timer
   #ifdef WIRING
-    if (timer == _timer1) {
-      CBI(
-        #if defined(__AVR_ATmega1281__) || defined(__AVR_ATmega2561__)
-          TIMSK1
-        #else
-          TIMSK
-        #endif
-          , OCIE1A);    // disable timer 1 output compare interrupt
-      timerDetach(TIMER1OUTCOMPAREA_INT);
-    }
-    else if (timer == _timer3) {
-      CBI(
-        #if defined(__AVR_ATmega1281__) || defined(__AVR_ATmega2561__)
-          TIMSK3
-        #else
-          ETIMSK
-        #endif
-          , OCIE3A);    // disable the timer3 output compare A interrupt
-      timerDetach(TIMER3OUTCOMPAREA_INT);
+    switch (timer_index) {
+      default: break;
+
+      case _timer1:
+        CBI(
+          #if defined(__AVR_ATmega1281__) || defined(__AVR_ATmega2561__)
+            TIMSK1
+          #else
+            TIMSK
+          #endif
+          , OCIE1A    // disable timer 1 output compare interrupt
+        );
+        timerDetach(TIMER1OUTCOMPAREA_INT);
+        break;
+
+      case _timer3:
+        CBI(
+          #if defined(__AVR_ATmega1281__) || defined(__AVR_ATmega2561__)
+            TIMSK3
+          #else
+            ETIMSK
+          #endif
+          , OCIE3A    // disable the timer3 output compare A interrupt
+        );
+        timerDetach(TIMER3OUTCOMPAREA_INT);
+        break;
     }
   #else // !WIRING
     // For arduino - in future: call here to a currently undefined function to reset the timer
-    UNUSED(timer);
+    UNUSED(timer_index);
   #endif
 }
 

Marlin/src/HAL/AVR/endstop_interrupts.h

@@ -213,6 +213,51 @@ void setup_endstop_interrupts() {
       pciSetup(K_MIN_PIN);
     #endif
   #endif
+  #if HAS_U_MAX
+    #if (digitalPinToInterrupt(U_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(U_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(U_MAX_PIN), "U_MAX_PIN is not interrupt-capable");
+      pciSetup(U_MAX_PIN);
+    #endif
+  #elif HAS_U_MIN
+    #if (digitalPinToInterrupt(U_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(U_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(U_MIN_PIN), "U_MIN_PIN is not interrupt-capable");
+      pciSetup(U_MIN_PIN);
+    #endif
+  #endif
+  #if HAS_V_MAX
+    #if (digitalPinToInterrupt(V_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(V_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(V_MAX_PIN), "V_MAX_PIN is not interrupt-capable");
+      pciSetup(V_MAX_PIN);
+    #endif
+  #elif HAS_V_MIN
+    #if (digitalPinToInterrupt(V_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(V_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(V_MIN_PIN), "V_MIN_PIN is not interrupt-capable");
+      pciSetup(V_MIN_PIN);
+    #endif
+  #endif
+  #if HAS_W_MAX
+    #if (digitalPinToInterrupt(W_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(W_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(W_MAX_PIN), "W_MAX_PIN is not interrupt-capable");
+      pciSetup(W_MAX_PIN);
+    #endif
+  #elif HAS_W_MIN
+    #if (digitalPinToInterrupt(W_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(W_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(W_MIN_PIN), "W_MIN_PIN is not interrupt-capable");
+      pciSetup(W_MIN_PIN);
+    #endif
+  #endif
   #if HAS_X2_MAX
     #if (digitalPinToInterrupt(X2_MAX_PIN) != NOT_AN_INTERRUPT)
       _ATTACH(X2_MAX_PIN);

Marlin/src/HAL/AVR/fast_pwm.cpp

@@ -23,6 +23,10 @@
 
 #include "../../inc/MarlinConfig.h"
 
+//#define DEBUG_AVR_FAST_PWM
+#define DEBUG_OUT ENABLED(DEBUG_AVR_FAST_PWM)
+#include "../../core/debug_out.h"
+
 struct Timer {
   volatile uint8_t* TCCRnQ[3];  // max 3 TCCR registers per timer
   volatile uint16_t* OCRnQ[3];  // max 3 OCR registers per timer
@@ -108,12 +112,15 @@ const Timer get_pwm_timer(const pin_t pin) {
 }
 
 void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
+  DEBUG_ECHOLNPGM("set_pwm_frequency(pin=", pin, ", freq=", f_desired, ")");
   const Timer timer = get_pwm_timer(pin);
   if (timer.isProtected || !timer.isPWM) return; // Don't proceed if protected timer or not recognized
 
   const bool is_timer2 = timer.n == 2;
   const uint16_t maxtop = is_timer2 ? 0xFF : 0xFFFF;
 
+  DEBUG_ECHOLNPGM("maxtop=", maxtop);
+
   uint16_t res = 0xFF;        // resolution (TOP value)
   uint8_t j = CS_NONE;        // prescaler index
   uint8_t wgm = WGM_PWM_PC_8; // waveform generation mode
@@ -121,23 +128,29 @@ void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
   // Calculating the prescaler and resolution to use to achieve closest frequency
   if (f_desired != 0) {
     constexpr uint16_t prescaler[] = { 1, 8, (32), 64, (128), 256, 1024 };  // (*) are Timer 2 only
-    uint16_t f = (F_CPU) / (2 * 1024 * maxtop) + 1;           // Start with the lowest non-zero frequency achievable (1 or 31)
+    uint16_t f = (F_CPU) / (uint32_t(maxtop) << 11) + 1;      // Start with the lowest non-zero frequency achievable (for 16MHz, 1 or 31)
 
+    DEBUG_ECHOLNPGM("f=", f);
+    DEBUG_ECHOLNPGM("(prescaler loop)");
     LOOP_L_N(i, COUNT(prescaler)) {                           // Loop through all prescaler values
-      const uint16_t p = prescaler[i];
+      const uint32_t p = prescaler[i];                        // Extend to 32 bits for calculations
+      DEBUG_ECHOLNPGM("prescaler[", i, "]=", p);
       uint16_t res_fast_temp, res_pc_temp;
       if (is_timer2) {
         #if ENABLED(USE_OCR2A_AS_TOP)                         // No resolution calculation for TIMER2 unless enabled USE_OCR2A_AS_TOP
           const uint16_t rft = (F_CPU) / (p * f_desired);
           res_fast_temp = rft - 1;
           res_pc_temp = rft / 2;
+          DEBUG_ECHOLNPGM("(Timer2) res_fast_temp=", res_fast_temp, " res_pc_temp=", res_pc_temp);
         #else
           res_fast_temp = res_pc_temp = maxtop;
+          DEBUG_ECHOLNPGM("(Timer2) res_fast_temp=", maxtop, " res_pc_temp=", maxtop);
         #endif
       }
       else {
         if (p == 32 || p == 128) continue;                    // Skip TIMER2 specific prescalers when not TIMER2
         const uint16_t rft = (F_CPU) / (p * f_desired);
+        DEBUG_ECHOLNPGM("(Not Timer 2) F_CPU=" STRINGIFY(F_CPU), " prescaler=", p, " f_desired=", f_desired);
         res_fast_temp = rft - 1;
         res_pc_temp = rft / 2;
       }
@@ -146,24 +159,28 @@ void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
       LIMIT(res_pc_temp, 1U, maxtop);
 
       // Calculate frequencies of test prescaler and resolution values
-      const uint32_t f_diff      = _MAX(f, f_desired) - _MIN(f, f_desired),
-                     f_fast_temp = (F_CPU) / (p * (1 + res_fast_temp)),
+      const uint16_t f_fast_temp = (F_CPU) / (p * (1 + res_fast_temp)),
+                     f_pc_temp   = (F_CPU) / ((p * res_pc_temp) << 1),
+                     f_diff      = _MAX(f, f_desired) - _MIN(f, f_desired),
                      f_fast_diff = _MAX(f_fast_temp, f_desired) - _MIN(f_fast_temp, f_desired),
-                     f_pc_temp   = (F_CPU) / (2 * p * res_pc_temp),
                      f_pc_diff   = _MAX(f_pc_temp, f_desired) - _MIN(f_pc_temp, f_desired);
 
+      DEBUG_ECHOLNPGM("f_fast_temp=", f_fast_temp, " f_pc_temp=", f_pc_temp, " f_diff=", f_diff, " f_fast_diff=", f_fast_diff, " f_pc_diff=", f_pc_diff);
+
       if (f_fast_diff < f_diff && f_fast_diff <= f_pc_diff) { // FAST values are closest to desired f
         // Set the Wave Generation Mode to FAST PWM
         wgm = is_timer2 ? uint8_t(TERN(USE_OCR2A_AS_TOP, WGM2_FAST_PWM_OCR2A, WGM2_FAST_PWM)) : uint8_t(WGM_FAST_PWM_ICRn);
         // Remember this combination
         f = f_fast_temp; res = res_fast_temp; j = i + 1;
+        DEBUG_ECHOLNPGM("(FAST) updated f=", f);
       }
       else if (f_pc_diff < f_diff) {                          // PHASE CORRECT values are closes to desired f
         // Set the Wave Generation Mode to PWM PHASE CORRECT
         wgm = is_timer2 ? uint8_t(TERN(USE_OCR2A_AS_TOP, WGM2_PWM_PC_OCR2A, WGM2_PWM_PC)) : uint8_t(WGM_PWM_PC_ICRn);
         f = f_pc_temp; res = res_pc_temp; j = i + 1;
+        DEBUG_ECHOLNPGM("(PHASE) updated f=", f);
       }
-    }
+    } // prescaler loop
   }
 
   _SET_WGMnQ(timer, wgm);

Marlin/src/HAL/AVR/fastio.h

@@ -293,11 +293,11 @@ enum ClockSource2 : uint8_t {
 
 #if HAS_MOTOR_CURRENT_PWM
   #if PIN_EXISTS(MOTOR_CURRENT_PWM_XY)
-    #define PWM_CHK_MOTOR_CURRENT(P) (P == MOTOR_CURRENT_PWM_E || P == MOTOR_CURRENT_PWM_Z || P == MOTOR_CURRENT_PWM_XY)
+    #define PWM_CHK_MOTOR_CURRENT(P) (P == MOTOR_CURRENT_PWM_E_PIN || P == MOTOR_CURRENT_PWM_E0_PIN  || P == MOTOR_CURRENT_PWM_E1_PIN || P == MOTOR_CURRENT_PWM_Z_PIN || P == MOTOR_CURRENT_PWM_XY_PIN)
   #elif PIN_EXISTS(MOTOR_CURRENT_PWM_Z)
-    #define PWM_CHK_MOTOR_CURRENT(P) (P == MOTOR_CURRENT_PWM_E || P == MOTOR_CURRENT_PWM_Z)
+    #define PWM_CHK_MOTOR_CURRENT(P) (P == MOTOR_CURRENT_PWM_E_PIN || P == MOTOR_CURRENT_PWM_E0_PIN  || P == MOTOR_CURRENT_PWM_E1_PIN || P == MOTOR_CURRENT_PWM_Z_PIN)
   #else
-    #define PWM_CHK_MOTOR_CURRENT(P) (P == MOTOR_CURRENT_PWM_E)
+    #define PWM_CHK_MOTOR_CURRENT(P) (P == MOTOR_CURRENT_PWM_E_PIN || P == MOTOR_CURRENT_PWM_E0_PIN  || P == MOTOR_CURRENT_PWM_E1_PIN)
   #endif
 #else
   #define PWM_CHK_MOTOR_CURRENT(P) false

Marlin/src/HAL/AVR/fastio/fastio_1280.h

@@ -27,6 +27,9 @@
  *   Hardware Pin  : 02 03 06 07 01 05 15 16 17 18 23 24 25 26 64 63 13 12 46 45 44 43 78 77 76 75 74 73 72 71 60 59 58 57 56 55 54 53 50 70 52 51 42 41 40 39 38 37 36 35 22 21 20 19 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 | 04 08 09 10 11 14 27 28 29 30 31 32 33 34 47 48 49 61 62 65 66 67 68 69 79 80 81 98 99 100
  *   Port          : E0 E1 E4 E5 G5 E3 H3 H4 H5 H6 B4 B5 B6 B7 J1 J0 H1 H0 D3 D2 D1 D0 A0 A1 A2 A3 A4 A5 A6 A7 C7 C6 C5 C4 C3 C2 C1 C0 D7 G2 G1 G0 L7 L6 L5 L4 L3 L2 L1 L0 B3 B2 B1 B0 F0 F1 F2 F3 F4 F5 F6 F7 K0 K1 K2 K3 K4 K5 K6 K7 | E2 E6 E7 xx xx H2 H7 G3 G4 xx xx xx xx xx D4 D5 D6 xx xx J2 J3 J4 J5 J6 J7 xx xx xx xx xx
  *   Logical Pin   : 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | 78 79 80 xx xx 84 85 71 70 xx xx xx xx xx 81 82 83 xx xx 72 73 75 76 77 74 xx xx xx xx xx
+ *
+ * Arduino Pin Layout video: https://youtu.be/rIqeVCX09FA
+ * AVR alternate pin function overview video: https://youtu.be/1yd8wuI5Plg
  */
 
 #include "../fastio.h"

Marlin/src/HAL/AVR/fastio/fastio_1281.h

@@ -26,6 +26,9 @@
  *
  *   Logical Pin: 38 39 40 41 42 43 44 45 16 10 11 12 06 07 08 09 30 31 32 33 34 35 36 37 17 18 19 20 21 22 23 24 00 01 13 05 02 03 14 15 46 47 48 49 50 51 52 53 25 26 27 28 29 04
  *   Port:        A0 A1 A2 A3 A4 A5 A6 A7 B0 B1 B2 B3 B4 B5 B6 B7 C0 C1 C2 C3 C4 C5 C6 C7 D0 D1 D2 D3 D4 D5 D6 D7 E0 E1 E2 E3 E4 E5 E6 E7 F0 F1 F2 F3 F4 F5 F6 F7 G0 G1 G2 G3 G4 G5
+ *
+ * Arduino Pin Layout video: https://youtu.be/rIqeVCX09FA
+ * AVR alternate pin function overview video: https://youtu.be/1yd8wuI5Plg
  */
 
 #include "../fastio.h"

Marlin/src/HAL/AVR/fastio/fastio_168.h

@@ -26,6 +26,9 @@
  *
  *   Logical Pin: 08 09 10 11 12 13 14 15 16 17 18 19 20 21 00 01 02 03 04 05 06 07
  *   Port:        B0 B1 B2 B3 B4 B5 C0 C1 C2 C3 C4 C5 C6 C7 D0 D1 D2 D3 D4 D5 D6 D7
+ *
+ * Arduino Pin Layout video: https://youtu.be/rIqeVCX09FA
+ * AVR alternate pin function overview video: https://youtu.be/1yd8wuI5Plg
  */
 
 #include "../fastio.h"

Marlin/src/HAL/AVR/fastio/fastio_644.h

@@ -26,6 +26,9 @@
  *
  *   Logical Pin: 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
  *   Port:        B0 B1 B2 B3 B4 B5 B6 B7 D0 D1 D2 D3 D4 D5 D6 D7 C0 C1 C2 C3 C4 C5 C6 C7 A7 A6 A5 A4 A3 A2 A1 A0
+ *
+ * Arduino Pin Layout video: https://youtu.be/rIqeVCX09FA
+ * AVR alternate pin function overview video: https://youtu.be/1yd8wuI5Plg
  */
 
 /**                        ATMega644

Marlin/src/HAL/AVR/fastio/fastio_AT90USB.h

@@ -27,6 +27,9 @@
  *   Logical Pin: 28 29 30 31 32 33 34 35 20 21 22 23 24 25 26 27 10 11 12 13 14 15 16 17 00 01 02 03 04 05 06 07 08 09(46*47)36 37 18 19 38 39 40 41 42 43 44 45
  *   Port:        A0 A1 A2 A3 A4 A5 A6 A7 B0 B1 B2 B3 B4 B5 B6 B7 C0 C1 C2 C3 C4 C5 C6 C7 D0 D1 D2 D3 D4 D5 D6 D7 E0 E1 E2 E3 E4 E5 E6 E7 F0 F1 F2 F3 F4 F5 F6 F7
  *            The logical pins 46 and 47 are not supported by Teensyduino, but are supported below as E2 and E3
+ *
+ * Arduino Pin Layout video: https://youtu.be/rIqeVCX09FA
+ * AVR alternate pin function overview video: https://youtu.be/1yd8wuI5Plg
  */
 
 #include "../fastio.h"

Marlin/src/HAL/AVR/inc/Conditionals_LCD.h

@@ -20,7 +20,3 @@
  *
  */
 #pragma once
-
-#if HAS_SPI_TFT || HAS_FSMC_TFT
-  #error "Sorry! TFT displays are not available for HAL/AVR."
-#endif

Marlin/src/HAL/AVR/inc/SanityCheck.h

@@ -25,6 +25,10 @@
  * Test AVR-specific configuration values for errors at compile-time.
  */
 
+#if HAS_SPI_TFT || HAS_FSMC_TFT
+  #error "Sorry! TFT displays are not available for HAL/AVR."
+#endif
+
 /**
  * Check for common serial pin conflicts
  */
@@ -35,16 +39,26 @@
   || X_STEP_PIN == N || Y_STEP_PIN == N || Z_STEP_PIN == N \
   || X_DIR_PIN  == N || Y_DIR_PIN  == N || Z_DIR_PIN  == N \
   || X_ENA_PIN  == N || Y_ENA_PIN  == N || Z_ENA_PIN  == N \
+  || BTN_EN1    == N || BTN_EN2    == N \
 )
-#if CONF_SERIAL_IS(0) // D0-D1. No known conflicts.
+#if SERIAL_IN_USE(0)
+  // D0-D1. No known conflicts.
 #endif
-#if CONF_SERIAL_IS(1) && (CHECK_SERIAL_PIN(18) || CHECK_SERIAL_PIN(19))
-  #error "Serial Port 1 pin D18 and/or D19 conflicts with another pin on the board."
+#if SERIAL_IN_USE(1)
+  #if NOT_TARGET(__AVR_ATmega644P__, __AVR_ATmega1284P__)
+    #if CHECK_SERIAL_PIN(18) || CHECK_SERIAL_PIN(19)
+      #error "Serial Port 1 pin D18 and/or D19 conflicts with another pin on the board."
+    #endif
+  #else
+    #if CHECK_SERIAL_PIN(10) || CHECK_SERIAL_PIN(11)
+      #error "Serial Port 1 pin D10 and/or D11 conflicts with another pin on the board."
+    #endif
+  #endif
 #endif
-#if CONF_SERIAL_IS(2) && (CHECK_SERIAL_PIN(16) || CHECK_SERIAL_PIN(17))
+#if SERIAL_IN_USE(2) && (CHECK_SERIAL_PIN(16) || CHECK_SERIAL_PIN(17))
   #error "Serial Port 2 pin D16 and/or D17 conflicts with another pin on the board."
 #endif
-#if CONF_SERIAL_IS(3) && (CHECK_SERIAL_PIN(14) || CHECK_SERIAL_PIN(15))
+#if SERIAL_IN_USE(3) && (CHECK_SERIAL_PIN(14) || CHECK_SERIAL_PIN(15))
   #error "Serial Port 3 pin D14 and/or D15 conflicts with another pin on the board."
 #endif
 #undef CHECK_SERIAL_PIN

Marlin/src/HAL/AVR/math.h

@@ -27,13 +27,14 @@
 
 // intRes = longIn1 * longIn2 >> 24
 // uses:
-// A[tmp] to store 0
-// B[tmp] to store bits 16-23 of the 48bit result. The top bit is used to round the two byte result.
-// note that the lower two bytes and the upper byte of the 48bit result are not calculated.
-// this can cause the result to be out by one as the lower bytes may cause carries into the upper ones.
-// B A are bits 24-39 and are the returned value
-// C B A is longIn1
-// D C B A is longIn2
+// r1, r0 for the result of mul.
+// [tmp1] to store 0.
+// [tmp2] to store bits 16-23 of the 56 bit result. The top bit of [tmp2] is used for rounding.
+// Note that the lower two bytes and the upper two bytes of the 56 bit result are not calculated.
+// This can cause the result to be out by one as the lower bytes may cause carries into the upper ones.
+// [intRes] (A B) is bits 24-39 and is the returned value.
+// [longIn1] (C B A) is a 24 bit parameter.
+// [longIn2] (D C B A) is a 32 bit parameter.
 //
 FORCE_INLINE static uint16_t MultiU24X32toH16(uint32_t longIn1, uint32_t longIn2) {
   uint8_t tmp1;
@@ -66,11 +67,9 @@ FORCE_INLINE static uint16_t MultiU24X32toH16(uint32_t longIn1, uint32_t longIn2
     A("add %[tmp2], r1")
     A("adc %A[intRes], %[tmp1]")
     A("adc %B[intRes], %[tmp1]")
-    A("lsr %[tmp2]")
-    A("adc %A[intRes], %[tmp1]")
-    A("adc %B[intRes], %[tmp1]")
     A("mul %D[longIn2], %A[longIn1]")
-    A("add %A[intRes], r0")
+    A("lsl %[tmp2]")
+    A("adc %A[intRes], r0")
     A("adc %B[intRes], r1")
     A("mul %D[longIn2], %B[longIn1]")
     A("add %B[intRes], r0")
@@ -85,11 +84,16 @@ FORCE_INLINE static uint16_t MultiU24X32toH16(uint32_t longIn1, uint32_t longIn2
   return intRes;
 }
 
-// intRes = intIn1 * intIn2 >> 16
+// intRes = intIn1 * intIn2 >> 8
 // uses:
-// r26 to store 0
-// r27 to store the byte 1 of the 24 bit result
-FORCE_INLINE static uint16_t MultiU16X8toH16(uint8_t charIn1, uint16_t intIn2) {
+// r1, r0 for the result of mul. After the second mul, r0 holds bits 0-7 of the 24 bit result and
+// the top bit of r0 is used for rounding.
+// [tmp] to store 0.
+// [intRes] (A B) is bits 8-15 and is the returned value.
+// [charIn1] is an 8 bit parameter.
+// [intIn2] (B A) is a 16 bit parameter.
+//
+FORCE_INLINE static uint16_t MultiU8X16toH16(uint8_t charIn1, uint16_t intIn2) {
   uint8_t tmp;
   uint16_t intRes;
   __asm__ __volatile__ (
@@ -97,10 +101,8 @@ FORCE_INLINE static uint16_t MultiU16X8toH16(uint8_t charIn1, uint16_t intIn2) {
     A("mul %[charIn1], %B[intIn2]")
     A("movw %A[intRes], r0")
     A("mul %[charIn1], %A[intIn2]")
-    A("add %A[intRes], r1")
-    A("adc %B[intRes], %[tmp]")
-    A("lsr r0")
-    A("adc %A[intRes], %[tmp]")
+    A("lsl r0")
+    A("adc %A[intRes], r1")
     A("adc %B[intRes], %[tmp]")
     A("clr r1")
       : [intRes] "=&r" (intRes),

Marlin/src/HAL/AVR/pinsDebug.h

@@ -64,11 +64,13 @@
 
 #define VALID_PIN(pin) (pin >= 0 && pin < NUM_DIGITAL_PINS ? 1 : 0)
 #if AVR_ATmega1284_FAMILY
-  #define DIGITAL_PIN_TO_ANALOG_PIN(P) int(analogInputToDigitalPin(0) - (P))
-  #define IS_ANALOG(P) ((P) >= analogInputToDigitalPin(7) && (P) <= analogInputToDigitalPin(0))
+  #define IS_ANALOG(P) WITHIN(P, analogInputToDigitalPin(7), analogInputToDigitalPin(0))
+  #define DIGITAL_PIN_TO_ANALOG_PIN(P) int(IS_ANALOG(P) ? (P) - analogInputToDigitalPin(7) : -1)
 #else
-  #define DIGITAL_PIN_TO_ANALOG_PIN(P) int((P) - analogInputToDigitalPin(0))
-  #define IS_ANALOG(P) ((P) >= analogInputToDigitalPin(0) && ((P) <= analogInputToDigitalPin(15) || (P) <= analogInputToDigitalPin(7)))
+  #define _ANALOG1(P) WITHIN(P, analogInputToDigitalPin(0), analogInputToDigitalPin(7))
+  #define _ANALOG2(P) WITHIN(P, analogInputToDigitalPin(8), analogInputToDigitalPin(15))
+  #define IS_ANALOG(P) (_ANALOG1(P) || _ANALOG2(P))
+  #define DIGITAL_PIN_TO_ANALOG_PIN(P) int(_ANALOG1(P) ? (P) - analogInputToDigitalPin(0) : _ANALOG2(P) ? (P) - analogInputToDigitalPin(8) + 8 : -1)
 #endif
 #define GET_ARRAY_PIN(p) pgm_read_byte(&pin_array[p].pin)
 #define MULTI_NAME_PAD 26 // space needed to be pretty if not first name assigned to a pin

Marlin/src/HAL/AVR/timers.h

@@ -44,14 +44,14 @@ typedef uint16_t hal_timer_t;
   #define MF_TIMER_TEMP         0
 #endif
 
-#define TEMP_TIMER_FREQUENCY    ((F_CPU) / 64.0 / 256.0)
+#define TEMP_TIMER_FREQUENCY    (((F_CPU) + 0x2000) / 0x4000)
 
 #define STEPPER_TIMER_RATE      HAL_TIMER_RATE
 #define STEPPER_TIMER_PRESCALE  8
-#define STEPPER_TIMER_TICKS_PER_US ((STEPPER_TIMER_RATE) / 1000000) // Cannot be of type double
+#define STEPPER_TIMER_TICKS_PER_US ((STEPPER_TIMER_RATE) / 1000000)
 
-#define PULSE_TIMER_RATE       STEPPER_TIMER_RATE   // frequency of pulse timer
-#define PULSE_TIMER_PRESCALE   STEPPER_TIMER_PRESCALE
+#define PULSE_TIMER_RATE         STEPPER_TIMER_RATE
+#define PULSE_TIMER_PRESCALE     STEPPER_TIMER_PRESCALE
 #define PULSE_TIMER_TICKS_PER_US STEPPER_TIMER_TICKS_PER_US
 
 #define ENABLE_STEPPER_DRIVER_INTERRUPT()  SBI(TIMSK1, OCIE1A)

Marlin/src/HAL/DUE/HAL.h

@@ -210,7 +210,7 @@ public:
   static void adc_init() {}
 
   // Called by Temperature::init for each sensor at startup
-  static void adc_enable(const uint8_t ch) {}
+  static void adc_enable(const uint8_t /*ch*/) {}
 
   // Begin ADC sampling on the given channel. Called from Temperature::isr!
   static void adc_start(const uint8_t ch) { adc_result = analogRead(ch); }

Marlin/src/HAL/DUE/HAL_SPI.cpp

@@ -247,12 +247,12 @@
       b <<= 1; // little setup time
 
       WRITE(SD_SCK_PIN, HIGH);
-      DELAY_NS(spiDelayNS);
+      DELAY_NS_VAR(spiDelayNS);
 
       b |= (READ(SD_MISO_PIN) != 0);
 
       WRITE(SD_SCK_PIN, LOW);
-      DELAY_NS(spiDelayNS);
+      DELAY_NS_VAR(spiDelayNS);
     } while (--bits);
     return b;
   }

Marlin/src/HAL/DUE/InterruptVectors.cpp

@@ -41,7 +41,7 @@
    practice, we need alignment to 256 bytes to make this work in all
    cases */
 __attribute__ ((aligned(256)))
-static DeviceVectors ram_tab = { nullptr };
+static DeviceVectors ram_tab[61] = { nullptr };
 
 /**
  * This function checks if the exception/interrupt table is already in SRAM or not.

Marlin/src/HAL/DUE/Servo.cpp

@@ -47,12 +47,12 @@
 #include "../shared/servo.h"
 #include "../shared/servo_private.h"
 
-static volatile int8_t Channel[_Nbr_16timers];              // counter for the servo being pulsed for each timer (or -1 if refresh interval)
+static Flags<_Nbr_16timers> DisablePending; // ISR should disable the timer at the next timer reset
 
 // ------------------------
 /// Interrupt handler for the TC0 channel 1.
 // ------------------------
-void Servo_Handler(timer16_Sequence_t timer, Tc *pTc, uint8_t channel);
+void Servo_Handler(const timer16_Sequence_t, Tc*, const uint8_t);
 
 #ifdef _useTimer1
   void HANDLER_FOR_TIMER1() { Servo_Handler(_timer1, TC_FOR_TIMER1, CHANNEL_FOR_TIMER1); }
@@ -70,88 +70,92 @@ void Servo_Handler(timer16_Sequence_t timer, Tc *pTc, uint8_t channel);
   void HANDLER_FOR_TIMER5() { Servo_Handler(_timer5, TC_FOR_TIMER5, CHANNEL_FOR_TIMER5); }
 #endif
 
-void Servo_Handler(timer16_Sequence_t timer, Tc *tc, uint8_t channel) {
-  // clear interrupt
-  tc->TC_CHANNEL[channel].TC_SR;
-  if (Channel[timer] < 0)
-    tc->TC_CHANNEL[channel].TC_CCR |= TC_CCR_SWTRG; // channel set to -1 indicated that refresh interval completed so reset the timer
-  else if (SERVO_INDEX(timer, Channel[timer]) < ServoCount && SERVO(timer, Channel[timer]).Pin.isActive)
-    extDigitalWrite(SERVO(timer, Channel[timer]).Pin.nbr, LOW); // pulse this channel low if activated
+void Servo_Handler(const timer16_Sequence_t timer, Tc *tc, const uint8_t channel) {
+  static int8_t Channel[_Nbr_16timers];                               // Servo counters to pulse (or -1 for refresh interval)
+  int8_t cho = Channel[timer];                                        // Handle the prior Channel[timer] first
+  if (cho < 0) {                                                      // Channel -1 indicates the refresh interval completed...
+    tc->TC_CHANNEL[channel].TC_CCR |= TC_CCR_SWTRG;                   // ...so reset the timer
+    if (DisablePending[timer]) {
+      // Disabling only after the full servo period expires prevents
+      // pulses being too close together if immediately re-enabled.
+      DisablePending.clear(timer);
+      TC_Stop(tc, channel);
+      tc->TC_CHANNEL[channel].TC_SR;                                  // clear interrupt
+      return;
+    }
+  }
+  else if (SERVO_INDEX(timer, cho) < ServoCount)                      // prior channel handled?
+    extDigitalWrite(SERVO(timer, cho).Pin.nbr, LOW);                  // pulse the prior channel LOW
 
-  Channel[timer]++;    // increment to the next channel
-  if (SERVO_INDEX(timer, Channel[timer]) < ServoCount && Channel[timer] < SERVOS_PER_TIMER) {
-    tc->TC_CHANNEL[channel].TC_RA = tc->TC_CHANNEL[channel].TC_CV + SERVO(timer,Channel[timer]).ticks;
-    if (SERVO(timer,Channel[timer]).Pin.isActive)    // check if activated
-      extDigitalWrite(SERVO(timer, Channel[timer]).Pin.nbr, HIGH); // its an active channel so pulse it high
+  Channel[timer] = ++cho;                                             // go to the next channel (or 0)
+  if (cho < SERVOS_PER_TIMER && SERVO_INDEX(timer, cho) < ServoCount) {
+    tc->TC_CHANNEL[channel].TC_RA = tc->TC_CHANNEL[channel].TC_CV + SERVO(timer, cho).ticks;
+    if (SERVO(timer, cho).Pin.isActive)                               // activated?
+      extDigitalWrite(SERVO(timer, cho).Pin.nbr, HIGH);               // yes: pulse HIGH
   }
   else {
     // finished all channels so wait for the refresh period to expire before starting over
-    tc->TC_CHANNEL[channel].TC_RA =
-      tc->TC_CHANNEL[channel].TC_CV < usToTicks(REFRESH_INTERVAL) - 4
-        ? (unsigned int)usToTicks(REFRESH_INTERVAL) // allow a few ticks to ensure the next OCR1A not missed
-        : tc->TC_CHANNEL[channel].TC_CV + 4;        // at least REFRESH_INTERVAL has elapsed
-    Channel[timer] = -1; // this will get incremented at the end of the refresh period to start again at the first channel
+    const unsigned int cval = tc->TC_CHANNEL[channel].TC_CV + 128 / (SERVO_TIMER_PRESCALER), // allow 128 cycles to ensure the next CV not missed
+                       ival = (unsigned int)usToTicks(REFRESH_INTERVAL); // at least REFRESH_INTERVAL has elapsed
+    tc->TC_CHANNEL[channel].TC_RA = max(cval, ival);
+
+    Channel[timer] = -1;                                              // reset the timer CCR on the next call
   }
+
+  tc->TC_CHANNEL[channel].TC_SR;                                      // clear interrupt
 }
 
 static void _initISR(Tc *tc, uint32_t channel, uint32_t id, IRQn_Type irqn) {
   pmc_enable_periph_clk(id);
   TC_Configure(tc, channel,
-    TC_CMR_TCCLKS_TIMER_CLOCK3 | // MCK/32
-    TC_CMR_WAVE |                // Waveform mode
-    TC_CMR_WAVSEL_UP_RC );       // Counter running up and reset when equals to RC
+      TC_CMR_WAVE                   // Waveform mode
+    | TC_CMR_WAVSEL_UP_RC           // Counter running up and reset when equal to RC
+    | (SERVO_TIMER_PRESCALER ==   2 ? TC_CMR_TCCLKS_TIMER_CLOCK1 : 0) // MCK/2
+    | (SERVO_TIMER_PRESCALER ==   8 ? TC_CMR_TCCLKS_TIMER_CLOCK2 : 0) // MCK/8
+    | (SERVO_TIMER_PRESCALER ==  32 ? TC_CMR_TCCLKS_TIMER_CLOCK3 : 0) // MCK/32
+    | (SERVO_TIMER_PRESCALER == 128 ? TC_CMR_TCCLKS_TIMER_CLOCK4 : 0) // MCK/128
+  );
 
-  /* 84MHz, MCK/32, for 1.5ms: 3937 */
-  TC_SetRA(tc, channel, 2625); // 1ms
+  // Wait 1ms before the first ISR
+  TC_SetRA(tc, channel, (F_CPU) / (SERVO_TIMER_PRESCALER) / 1000UL); // 1ms
 
-  /* Configure and enable interrupt */
+  // Configure and enable interrupt
   NVIC_EnableIRQ(irqn);
-  // TC_IER_CPAS: RA Compare
-  tc->TC_CHANNEL[channel].TC_IER = TC_IER_CPAS;
+  tc->TC_CHANNEL[channel].TC_IER = TC_IER_CPAS; // TC_IER_CPAS: RA Compare
 
   // Enables the timer clock and performs a software reset to start the counting
   TC_Start(tc, channel);
 }
 
-void initISR(timer16_Sequence_t timer) {
-  #ifdef _useTimer1
-    if (timer == _timer1)
-      _initISR(TC_FOR_TIMER1, CHANNEL_FOR_TIMER1, ID_TC_FOR_TIMER1, IRQn_FOR_TIMER1);
-  #endif
-  #ifdef _useTimer2
-    if (timer == _timer2)
-      _initISR(TC_FOR_TIMER2, CHANNEL_FOR_TIMER2, ID_TC_FOR_TIMER2, IRQn_FOR_TIMER2);
-  #endif
-  #ifdef _useTimer3
-    if (timer == _timer3)
-      _initISR(TC_FOR_TIMER3, CHANNEL_FOR_TIMER3, ID_TC_FOR_TIMER3, IRQn_FOR_TIMER3);
-  #endif
-  #ifdef _useTimer4
-    if (timer == _timer4)
-      _initISR(TC_FOR_TIMER4, CHANNEL_FOR_TIMER4, ID_TC_FOR_TIMER4, IRQn_FOR_TIMER4);
-  #endif
-  #ifdef _useTimer5
-    if (timer == _timer5)
-      _initISR(TC_FOR_TIMER5, CHANNEL_FOR_TIMER5, ID_TC_FOR_TIMER5, IRQn_FOR_TIMER5);
-  #endif
+void initISR(const timer16_Sequence_t timer_index) {
+  CRITICAL_SECTION_START();
+  const bool disable_soon = DisablePending[timer_index];
+  DisablePending.clear(timer_index);
+  CRITICAL_SECTION_END();
+
+  if (!disable_soon) switch (timer_index) {
+    default: break;
+    #ifdef _useTimer1
+      case _timer1: return _initISR(TC_FOR_TIMER1, CHANNEL_FOR_TIMER1, ID_TC_FOR_TIMER1, IRQn_FOR_TIMER1);
+    #endif
+    #ifdef _useTimer2
+      case _timer2: return _initISR(TC_FOR_TIMER2, CHANNEL_FOR_TIMER2, ID_TC_FOR_TIMER2, IRQn_FOR_TIMER2);
+    #endif
+    #ifdef _useTimer3
+      case _timer3: return _initISR(TC_FOR_TIMER3, CHANNEL_FOR_TIMER3, ID_TC_FOR_TIMER3, IRQn_FOR_TIMER3);
+    #endif
+    #ifdef _useTimer4
+      case _timer4: return _initISR(TC_FOR_TIMER4, CHANNEL_FOR_TIMER4, ID_TC_FOR_TIMER4, IRQn_FOR_TIMER4);
+    #endif
+    #ifdef _useTimer5
+      case _timer5: return _initISR(TC_FOR_TIMER5, CHANNEL_FOR_TIMER5, ID_TC_FOR_TIMER5, IRQn_FOR_TIMER5);
+    #endif
+  }
 }
 
-void finISR(timer16_Sequence_t) {
-  #ifdef _useTimer1
-    TC_Stop(TC_FOR_TIMER1, CHANNEL_FOR_TIMER1);
-  #endif
-  #ifdef _useTimer2
-    TC_Stop(TC_FOR_TIMER2, CHANNEL_FOR_TIMER2);
-  #endif
-  #ifdef _useTimer3
-    TC_Stop(TC_FOR_TIMER3, CHANNEL_FOR_TIMER3);
-  #endif
-  #ifdef _useTimer4
-    TC_Stop(TC_FOR_TIMER4, CHANNEL_FOR_TIMER4);
-  #endif
-  #ifdef _useTimer5
-    TC_Stop(TC_FOR_TIMER5, CHANNEL_FOR_TIMER5);
-  #endif
+void finISR(const timer16_Sequence_t timer_index) {
+  // Timer is disabled from the ISR, to ensure proper final pulse length.
+  DisablePending.set(timer_index);
 }
 
 #endif // HAS_SERVOS

Marlin/src/HAL/DUE/ServoTimers.h

@@ -37,7 +37,7 @@
 #define _useTimer5
 
 #define TRIM_DURATION             2   // compensation ticks to trim adjust for digitalWrite delays
-#define SERVO_TIMER_PRESCALER     32  // timer prescaler
+#define SERVO_TIMER_PRESCALER     2   // timer prescaler
 
 /*
   TC0, chan 0 => TC0_Handler

Marlin/src/HAL/DUE/endstop_interrupts.h

@@ -70,4 +70,10 @@ void setup_endstop_interrupts() {
   TERN_(HAS_J_MIN, _ATTACH(J_MIN_PIN));
   TERN_(HAS_K_MAX, _ATTACH(K_MAX_PIN));
   TERN_(HAS_K_MIN, _ATTACH(K_MIN_PIN));
+  TERN_(HAS_U_MAX, _ATTACH(U_MAX_PIN));
+  TERN_(HAS_U_MIN, _ATTACH(U_MIN_PIN));
+  TERN_(HAS_V_MAX, _ATTACH(V_MAX_PIN));
+  TERN_(HAS_V_MIN, _ATTACH(V_MIN_PIN));
+  TERN_(HAS_W_MAX, _ATTACH(W_MAX_PIN));
+  TERN_(HAS_W_MIN, _ATTACH(W_MIN_PIN));
 }

Marlin/src/HAL/DUE/inc/Conditionals_LCD.h

@@ -20,7 +20,3 @@
  *
  */
 #pragma once
-
-#if HAS_SPI_TFT || HAS_FSMC_TFT
-  #error "Sorry! TFT displays are not available for HAL/DUE."
-#endif

Marlin/src/HAL/DUE/inc/SanityCheck.h

@@ -25,6 +25,10 @@
  * Test Arduino Due specific configuration values for errors at compile-time.
  */
 
+#if HAS_SPI_TFT || HAS_FSMC_TFT
+  #error "Sorry! TFT displays are not available for HAL/DUE."
+#endif
+
 /**
  * Check for common serial pin conflicts
  */
@@ -36,15 +40,15 @@
   || X_DIR_PIN  == N || Y_DIR_PIN  == N || Z_DIR_PIN  == N \
   || X_ENA_PIN  == N || Y_ENA_PIN  == N || Z_ENA_PIN  == N \
 )
-#if CONF_SERIAL_IS(0) // D0-D1. No known conflicts.
+#if SERIAL_IN_USE(0) // D0-D1. No known conflicts.
 #endif
-#if CONF_SERIAL_IS(1) && (CHECK_SERIAL_PIN(18) || CHECK_SERIAL_PIN(19))
+#if SERIAL_IN_USE(1) && (CHECK_SERIAL_PIN(18) || CHECK_SERIAL_PIN(19))
   #error "Serial Port 1 pin D18 and/or D19 conflicts with another pin on the board."
 #endif
-#if CONF_SERIAL_IS(2) && (CHECK_SERIAL_PIN(16) || CHECK_SERIAL_PIN(17))
+#if SERIAL_IN_USE(2) && (CHECK_SERIAL_PIN(16) || CHECK_SERIAL_PIN(17))
   #error "Serial Port 2 pin D16 and/or D17 conflicts with another pin on the board."
 #endif
-#if CONF_SERIAL_IS(3) && (CHECK_SERIAL_PIN(14) || CHECK_SERIAL_PIN(15))
+#if SERIAL_IN_USE(3) && (CHECK_SERIAL_PIN(14) || CHECK_SERIAL_PIN(15))
   #error "Serial Port 3 pin D14 and/or D15 conflicts with another pin on the board."
 #endif
 #undef CHECK_SERIAL_PIN
@@ -77,7 +81,7 @@
 #endif
 
 #if ENABLED(FAST_PWM_FAN) || SPINDLE_LASER_FREQUENCY
-  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported on DUE."
+  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported for HAL/DUE."
 #endif
 
 #if HAS_TMC_SW_SERIAL

Marlin/src/HAL/DUE/pinsDebug.h

@@ -70,7 +70,7 @@
 #define PRINT_PIN_ANALOG(p) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), DIGITAL_PIN_TO_ANALOG_PIN(pin)); SERIAL_ECHO(buffer); }while(0)
 #define GET_ARRAY_PIN(p) pin_array[p].pin
 #define GET_ARRAY_IS_DIGITAL(p) pin_array[p].is_digital
-#define VALID_PIN(pin) (pin >= 0 && pin < (int8_t)NUMBER_PINS_TOTAL ? 1 : 0)
+#define VALID_PIN(pin) (pin >= 0 && pin < int8_t(NUMBER_PINS_TOTAL))
 #define DIGITAL_PIN_TO_ANALOG_PIN(p) int(p - analogInputToDigitalPin(0))
 #define IS_ANALOG(P) WITHIN(P, char(analogInputToDigitalPin(0)), char(analogInputToDigitalPin(NUM_ANALOG_INPUTS - 1)))
 #define pwm_status(pin) (((g_pinStatus[pin] & 0xF) == PIN_STATUS_PWM) && \

Marlin/src/HAL/DUE/timers.cpp

@@ -89,10 +89,17 @@ void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {
   NVIC_SetPriority(irq, timer_config[timer_num].priority);
 
   // wave mode, reset counter on match with RC,
-  TC_Configure(tc, channel, TC_CMR_WAVE | TC_CMR_WAVSEL_UP_RC | TC_CMR_TCCLKS_TIMER_CLOCK1);
+  TC_Configure(tc, channel,
+      TC_CMR_WAVE
+    | TC_CMR_WAVSEL_UP_RC
+    | (HAL_TIMER_PRESCALER ==   2 ? TC_CMR_TCCLKS_TIMER_CLOCK1 : 0)
+    | (HAL_TIMER_PRESCALER ==   8 ? TC_CMR_TCCLKS_TIMER_CLOCK2 : 0)
+    | (HAL_TIMER_PRESCALER ==  32 ? TC_CMR_TCCLKS_TIMER_CLOCK3 : 0)
+    | (HAL_TIMER_PRESCALER == 128 ? TC_CMR_TCCLKS_TIMER_CLOCK4 : 0)
+  );
 
   // Set compare value
-  TC_SetRC(tc, channel, VARIANT_MCK / 2 / frequency);
+  TC_SetRC(tc, channel, VARIANT_MCK / (HAL_TIMER_PRESCALER) / frequency);
 
   // And start timer
   TC_Start(tc, channel);

Marlin/src/HAL/DUE/timers.h

@@ -35,7 +35,8 @@
 typedef uint32_t hal_timer_t;
 #define HAL_TIMER_TYPE_MAX 0xFFFFFFFF
 
-#define HAL_TIMER_RATE         ((F_CPU) / 2)    // frequency of timers peripherals
+#define HAL_TIMER_PRESCALER    2
+#define HAL_TIMER_RATE         ((F_CPU) / (HAL_TIMER_PRESCALER))  // frequency of timers peripherals
 
 #ifndef MF_TIMER_STEP
   #define MF_TIMER_STEP         2  // Timer Index for Stepper

Marlin/src/HAL/DUE/upload_extra_script.py

@@ -6,14 +6,14 @@
 #
 import pioutil
 if pioutil.is_pio_build():
-	import platform
-	current_OS = platform.system()
+    import platform
+    current_OS = platform.system()
 
-	if current_OS == 'Windows':
+    if current_OS == 'Windows':
 
-		Import("env")
+        Import("env")
 
-		# Use bossac.exe on Windows
-		env.Replace(
-			UPLOADCMD="bossac --info --unlock --write --verify --reset --erase -U false --boot $SOURCE"
-		)
+        # Use bossac.exe on Windows
+        env.Replace(
+            UPLOADCMD="bossac --info --unlock --write --verify --reset --erase -U false --boot $SOURCE"
+        )

Marlin/src/HAL/DUE/usb/compiler.h

@@ -1059,7 +1059,7 @@ static inline void convert_64_bit_to_byte_array(uint64_t value, uint8_t *data)
     while (val_index < 8)
     {
         data[val_index++] = value & 0xFF;
-        value = value >> 8;
+        value >>= 8;
     }
 }
 

Marlin/src/HAL/DUE/usb/usb_task.c

@@ -62,7 +62,7 @@ void usb_task_idle(void) {
     // Attend SD card access from the USB MSD -- Prioritize access to improve speed
     int delay = 2;
     while (main_b_msc_enable && --delay > 0) {
-      if (udi_msc_process_trans()) delay = 10000;
+      if (udi_msc_process_trans()) delay = 20;
 
       // Reset the watchdog, just to be sure
       REG_WDT_CR = WDT_CR_WDRSTT | WDT_CR_KEY(0xA5);

Marlin/src/HAL/ESP32/HAL.cpp

@@ -65,6 +65,7 @@ portMUX_TYPE MarlinHAL::spinlock = portMUX_INITIALIZER_UNLOCKED;
 // ------------------------
 
 uint16_t MarlinHAL::adc_result;
+pwm_pin_t MarlinHAL::pwm_pin_data[MAX_EXPANDER_BITS];
 
 // ------------------------
 // Private Variables
@@ -330,14 +331,37 @@ int8_t get_pwm_channel(const pin_t pin, const uint32_t freq, const uint16_t res)
 }
 
 void MarlinHAL::set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=_BV(PWM_RESOLUTION)-1*/, const bool invert/*=false*/) {
+  #if ENABLED(I2S_STEPPER_STREAM)
+    if (pin > 127) {
+      const uint8_t pinlo = pin & 0x7F;
+      pwm_pin_t &pindata = pwm_pin_data[pinlo];
+      const uint32_t duty = map(invert ? v_size - v : v, 0, v_size, 0, pindata.pwm_cycle_ticks);
+      if (duty == 0 || duty == pindata.pwm_cycle_ticks) { // max or min (i.e., on/off)
+        pindata.pwm_duty_ticks = 0;  // turn off PWM for this pin
+        duty ? SBI32(i2s_port_data, pinlo) : CBI32(i2s_port_data, pinlo); // set pin level
+      }
+      else
+        pindata.pwm_duty_ticks = duty; // PWM duty count = # of 4µs ticks per full PWM cycle
+
+      return;
+    }
+  #endif
+
   const int8_t cid = get_pwm_channel(pin, PWM_FREQUENCY, PWM_RESOLUTION);
   if (cid >= 0) {
-    uint32_t duty = map(invert ? v_size - v : v, 0, v_size, 0, _BV(PWM_RESOLUTION)-1);
+    const uint32_t duty = map(invert ? v_size - v : v, 0, v_size, 0, _BV(PWM_RESOLUTION)-1);
     ledcWrite(cid, duty);
   }
 }
 
 int8_t MarlinHAL::set_pwm_frequency(const pin_t pin, const uint32_t f_desired) {
+  #if ENABLED(I2S_STEPPER_STREAM)
+    if (pin > 127) {
+      pwm_pin_data[pin & 0x7F].pwm_cycle_ticks = 1000000UL / f_desired / 4; // # of 4µs ticks per full PWM cycle
+      return 0;
+    }
+  #endif
+
   const int8_t cid = channel_for_pin(pin);
   if (cid >= 0) {
     if (f_desired == ledcReadFreq(cid)) return cid; // no freq change

Marlin/src/HAL/ESP32/HAL.h

@@ -50,24 +50,25 @@
 
 #define MYSERIAL1 flushableSerial
 
-#if EITHER(WIFISUPPORT, ESP3D_WIFISUPPORT)
-  #if ENABLED(ESP3D_WIFISUPPORT)
-    typedef ForwardSerial1Class< decltype(Serial2Socket) > DefaultSerial1;
-    extern DefaultSerial1 MSerial0;
-    #define MYSERIAL2 MSerial0
-  #else
-    #define MYSERIAL2 webSocketSerial
-  #endif
+#if ENABLED(ESP3D_WIFISUPPORT)
+  typedef ForwardSerial1Class< decltype(Serial2Socket) > DefaultSerial1;
+  extern DefaultSerial1 MSerial0;
+  #define MYSERIAL2 MSerial0
+#elif ENABLED(WIFISUPPORT)
+  #define MYSERIAL2 webSocketSerial
 #endif
 
-#define CRITICAL_SECTION_START() portENTER_CRITICAL(&spinlock)
-#define CRITICAL_SECTION_END()   portEXIT_CRITICAL(&spinlock)
+#define CRITICAL_SECTION_START() portENTER_CRITICAL(&hal.spinlock)
+#define CRITICAL_SECTION_END()   portEXIT_CRITICAL(&hal.spinlock)
 
 #define HAL_CAN_SET_PWM_FREQ   // This HAL supports PWM Frequency adjustment
 #define PWM_FREQUENCY  1000u   // Default PWM frequency when set_pwm_duty() is called without set_pwm_frequency()
 #define PWM_RESOLUTION   10u   // Default PWM bit resolution
 #define CHANNEL_MAX_NUM  15u   // max PWM channel # to allocate (7 to only use low speed, 15 to use low & high)
 #define MAX_PWM_IOPIN    33u   // hardware pwm pins < 34
+#ifndef MAX_EXPANDER_BITS
+  #define MAX_EXPANDER_BITS 32 // I2S expander bit width (max 32)
+#endif
 
 // ------------------------
 // Types
@@ -76,6 +77,12 @@
 typedef double isr_float_t;   // FPU ops are used for single-precision, so use double for ISRs.
 typedef int16_t pin_t;
 
+typedef struct pwm_pin {
+  uint32_t pwm_cycle_ticks = 1000000UL / (PWM_FREQUENCY) / 4; // # ticks per pwm cycle
+  uint32_t pwm_tick_count = 0;  // current tick count
+  uint32_t pwm_duty_ticks = 0;  // # of ticks for current duty cycle
+} pwm_pin_t;
+
 class Servo;
 typedef Servo hal_servo_t;
 
@@ -197,6 +204,8 @@ public:
   // Free SRAM
   static int freeMemory();
 
+  static pwm_pin_t pwm_pin_data[MAX_EXPANDER_BITS];
+
   //
   // ADC Methods
   //

Marlin/src/HAL/ESP32/endstop_interrupts.h

@@ -65,4 +65,10 @@ void setup_endstop_interrupts() {
   TERN_(HAS_J_MIN, _ATTACH(J_MIN_PIN));
   TERN_(HAS_K_MAX, _ATTACH(K_MAX_PIN));
   TERN_(HAS_K_MIN, _ATTACH(K_MIN_PIN));
+  TERN_(HAS_U_MAX, _ATTACH(U_MAX_PIN));
+  TERN_(HAS_U_MIN, _ATTACH(U_MIN_PIN));
+  TERN_(HAS_V_MAX, _ATTACH(V_MAX_PIN));
+  TERN_(HAS_V_MIN, _ATTACH(V_MIN_PIN));
+  TERN_(HAS_W_MAX, _ATTACH(W_MAX_PIN));
+  TERN_(HAS_W_MIN, _ATTACH(W_MIN_PIN));
 }

Marlin/src/HAL/ESP32/i2s.cpp

@@ -139,22 +139,38 @@ static void IRAM_ATTR i2s_intr_handler_default(void *arg) {
 }
 
 void stepperTask(void *parameter) {
-  uint32_t remaining = 0;
+  uint32_t nextMainISR = 0;
+  #if ENABLED(LIN_ADVANCE)
+    uint32_t nextAdvanceISR = Stepper::LA_ADV_NEVER;
+  #endif
 
-  while (1) {
+  for (;;) {
     xQueueReceive(dma.queue, &dma.current, portMAX_DELAY);
     dma.rw_pos = 0;
 
     while (dma.rw_pos < DMA_SAMPLE_COUNT) {
-      // Fill with the port data post pulse_phase until the next step
-      if (remaining) {
-        i2s_push_sample();
-        remaining--;
-      }
-      else {
+      if (!nextMainISR) {
         Stepper::pulse_phase_isr();
-        remaining = Stepper::block_phase_isr();
+        nextMainISR = Stepper::block_phase_isr();
       }
+      #if ENABLED(LIN_ADVANCE)
+        else if (!nextAdvanceISR) {
+          Stepper::advance_isr();
+          nextAdvanceISR = Stepper::la_interval;
+        }
+      #endif
+      else
+        i2s_push_sample();
+
+      nextMainISR--;
+
+      #if ENABLED(LIN_ADVANCE)
+        if (nextAdvanceISR == Stepper::LA_ADV_NEVER)
+          nextAdvanceISR = Stepper::la_interval;
+
+        if (nextAdvanceISR && nextAdvanceISR != Stepper::LA_ADV_NEVER)
+          nextAdvanceISR--;
+      #endif
     }
   }
 }
@@ -337,6 +353,26 @@ uint8_t i2s_state(uint8_t pin) {
 }
 
 void i2s_push_sample() {
+  // Every 4µs (when space in DMA buffer) toggle each expander PWM output using
+  // the current duty cycle/frequency so they sync with any steps (once
+  // through the DMA/FIFO buffers).  PWM signal inversion handled by other functions
+  LOOP_L_N(p, MAX_EXPANDER_BITS) {
+    if (hal.pwm_pin_data[p].pwm_duty_ticks > 0) { // pin has active pwm?
+      if (hal.pwm_pin_data[p].pwm_tick_count == 0) {
+        if (TEST32(i2s_port_data, p)) {  // hi->lo
+          CBI32(i2s_port_data, p);
+          hal.pwm_pin_data[p].pwm_tick_count = hal.pwm_pin_data[p].pwm_cycle_ticks - hal.pwm_pin_data[p].pwm_duty_ticks;
+        }
+        else { // lo->hi
+          SBI32(i2s_port_data, p);
+          hal.pwm_pin_data[p].pwm_tick_count = hal.pwm_pin_data[p].pwm_duty_ticks;
+        }
+      }
+      else
+        hal.pwm_pin_data[p].pwm_tick_count--;
+    }
+  }
+
   dma.current[dma.rw_pos++] = i2s_port_data;
 }
 

Marlin/src/HAL/ESP32/inc/Conditionals_LCD.h

@@ -20,7 +20,3 @@
  *
  */
 #pragma once
-
-#if HAS_SPI_TFT || HAS_FSMC_TFT
-  #error "Sorry! TFT displays are not available for HAL/ESP32."
-#endif

Marlin/src/HAL/ESP32/inc/Conditionals_adv.h

@@ -20,3 +20,10 @@
  *
  */
 #pragma once
+
+//
+// Board-specific options need to be defined before HAL.h
+//
+#if MB(MKS_TINYBEE)
+  #define MAX_EXPANDER_BITS 24  // TinyBee has 3 x HC595
+#endif

Marlin/src/HAL/ESP32/inc/SanityCheck.h

@@ -21,12 +21,19 @@
  */
 #pragma once
 
+#if HAS_SPI_TFT || HAS_FSMC_TFT
+  #error "Sorry! TFT displays are not available for HAL/ESP32."
+#endif
+
 #if ENABLED(EMERGENCY_PARSER)
   #error "EMERGENCY_PARSER is not yet implemented for ESP32. Disable EMERGENCY_PARSER to continue."
 #endif
 
-#if (ENABLED(SPINDLE_LASER_USE_PWM) && SPINDLE_LASER_FREQUENCY > 78125) || (ENABLED(FAST_PWM_FAN_FREQUENCY) && FAST_PWM_FAN_FREQUENCY > 78125)
-  #error "SPINDLE_LASER_FREQUENCY and FAST_PWM_FREQUENCY maximum value is 78125Hz for ESP32."
+#if ENABLED(SPINDLE_LASER_USE_PWM) && SPINDLE_LASER_FREQUENCY > 78125
+  #error "SPINDLE_LASER_FREQUENCY maximum value is 78125Hz for ESP32."
+#endif
+#if ENABLED(FAST_PWM_FAN) && FAST_PWM_FAN_FREQUENCY > 78125
+  #error "FAST_PWM_FREQUENCY maximum value is 78125Hz for ESP32."
 #endif
 
 #if HAS_TMC_SW_SERIAL
@@ -45,6 +52,18 @@
   #error "FAST_PWM_FAN is not available on TinyBee."
 #endif
 
+#if BOTH(I2S_STEPPER_STREAM, BABYSTEPPING) && DISABLED(INTEGRATED_BABYSTEPPING)
+  #error "BABYSTEPPING on I2S stream requires INTEGRATED_BABYSTEPPING."
+#endif
+
 #if USING_PULLDOWNS
   #error "PULLDOWN pin mode is not available on ESP32 boards."
 #endif
+
+#if BOTH(I2S_STEPPER_STREAM, LIN_ADVANCE) && DISABLED(EXPERIMENTAL_I2S_LA)
+  #error "I2S stream is currently incompatible with LIN_ADVANCE."
+#endif
+
+#if BOTH(I2S_STEPPER_STREAM, PRINTCOUNTER) && PRINTCOUNTER_SAVE_INTERVAL > 0 && DISABLED(PRINTCOUNTER_SYNC)
+  #error "PRINTCOUNTER_SAVE_INTERVAL may cause issues on ESP32 with an I2S expander. Define PRINTCOUNTER_SYNC in Configuration.h for an imperfect solution."
+#endif

Marlin/src/HAL/ESP32/timers.cpp

@@ -111,12 +111,12 @@ void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {
 /**
  * Set the upper value of the timer, when the timer reaches this upper value the
  * interrupt should be triggered and the counter reset
- * @param timer_num timer number to set the count to
- * @param count     threshold at which the interrupt is triggered
+ * @param timer_num timer number to set the compare value to
+ * @param compare   threshold at which the interrupt is triggered
  */
-void HAL_timer_set_compare(const uint8_t timer_num, hal_timer_t count) {
+void HAL_timer_set_compare(const uint8_t timer_num, const hal_timer_t compare) {
   const tTimerConfig timer = timer_config[timer_num];
-  timer_set_alarm_value(timer.group, timer.idx, count);
+  timer_set_alarm_value(timer.group, timer.idx, compare);
 }
 
 /**

Marlin/src/HAL/ESP32/u8g_esp32_spi.cpp

@@ -32,6 +32,13 @@
 #include "HAL.h"
 #include "SPI.h"
 
+#if ENABLED(SDSUPPORT)
+  #include "../../sd/cardreader.h"
+  #if ENABLED(ESP3D_WIFISUPPORT)
+    #include "sd_ESP32.h"
+  #endif
+#endif
+
 static SPISettings spiConfig;
 
 
@@ -45,6 +52,11 @@ static SPISettings spiConfig;
 
 uint8_t u8g_eps_hw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr) {
   static uint8_t msgInitCount = 2; // Ignore all messages until 2nd U8G_COM_MSG_INIT
+
+  #if ENABLED(PAUSE_LCD_FOR_BUSY_SD)
+    if (card.flag.saving || card.flag.logging || TERN0(ESP3D_WIFISUPPORT, sd_busy_lock == true)) return 0;
+  #endif
+
   if (msgInitCount) {
     if (msg == U8G_COM_MSG_INIT) msgInitCount--;
     if (msgInitCount) return -1;

Marlin/src/HAL/HAL.h

@@ -27,7 +27,7 @@
   #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
 #endif
 
-#include HAL_PATH(.,HAL.h)
+#include HAL_PATH(..,HAL.h)
 extern MarlinHAL hal;
 
 #define HAL_ADC_RANGE _BV(HAL_ADC_RESOLUTION)

Marlin/src/HAL/LINUX/eeprom.cpp

@@ -69,12 +69,12 @@ bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, ui
   std::size_t bytes_written = 0;
 
   for (std::size_t i = 0; i < size; i++) {
-    buffer[pos+i] = value[i];
-    bytes_written ++;
+    buffer[pos + i] = value[i];
+    bytes_written++;
   }
 
   crc16(crc, value, size);
-  pos = pos + size;
+  pos += size;
   return (bytes_written != size);  // return true for any error
 }
 
@@ -82,21 +82,21 @@ bool PersistentStore::read_data(int &pos, uint8_t *value, const size_t size, uin
   std::size_t bytes_read = 0;
   if (writing) {
     for (std::size_t i = 0; i < size; i++) {
-      value[i] = buffer[pos+i];
-      bytes_read ++;
+      value[i] = buffer[pos + i];
+      bytes_read++;
     }
     crc16(crc, value, size);
   }
   else {
     uint8_t temp[size];
     for (std::size_t i = 0; i < size; i++) {
-      temp[i] = buffer[pos+i];
-      bytes_read ++;
+      temp[i] = buffer[pos + i];
+      bytes_read++;
     }
     crc16(crc, temp, size);
   }
 
-  pos = pos + size;
+  pos += size;
   return bytes_read != size;  // return true for any error
 }
 

Marlin/src/HAL/LINUX/hardware/Heater.h

@@ -26,8 +26,8 @@
 struct LowpassFilter {
   uint64_t data_delay = 0;
   uint16_t update(uint16_t value) {
-    data_delay = data_delay - (data_delay >> 6) + value;
-    return (uint16_t)(data_delay >> 6);
+    data_delay += value - (data_delay >> 6);
+    return uint16_t(data_delay >> 6);
   }
 };
 

Marlin/src/HAL/LINUX/inc/Conditionals_LCD.h

@@ -20,7 +20,3 @@
  *
  */
 #pragma once
-
-#if HAS_SPI_TFT || HAS_FSMC_TFT
-  #error "Sorry! TFT displays are not available for HAL/LINUX."
-#endif

Marlin/src/HAL/LINUX/inc/SanityCheck.h

@@ -31,13 +31,17 @@
 #endif
 
 #if ENABLED(FAST_PWM_FAN) || SPINDLE_LASER_FREQUENCY
-  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported on LINUX."
+  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported for HAL/LINUX."
+#endif
+
+#if HAS_SPI_TFT || HAS_FSMC_TFT
+  #error "Sorry! TFT displays are not available for HAL/LINUX."
 #endif
 
 #if HAS_TMC_SW_SERIAL
-  #error "TMC220x Software Serial is not supported on LINUX."
+  #error "TMC220x Software Serial is not supported for HAL/LINUX."
 #endif
 
 #if ENABLED(POSTMORTEM_DEBUGGING)
-  #error "POSTMORTEM_DEBUGGING is not yet supported on LINUX."
+  #error "POSTMORTEM_DEBUGGING is not yet supported for HAL/LINUX."
 #endif

Marlin/src/HAL/LINUX/spi_pins.h

@@ -25,10 +25,10 @@
 #include "../../inc/MarlinConfigPre.h"
 
 #if BOTH(HAS_MARLINUI_U8GLIB, SDSUPPORT) && (LCD_PINS_D4 == SD_SCK_PIN || LCD_PINS_ENABLE == SD_MOSI_PIN || DOGLCD_SCK == SD_SCK_PIN || DOGLCD_MOSI == SD_MOSI_PIN)
-  #define LPC_SOFTWARE_SPI  // If the SD card and LCD adapter share the same SPI pins, then software SPI is currently
-                            // needed due to the speed and mode required for communicating with each device being different.
-                            // This requirement can be removed if the SPI access to these devices is updated to use
-                            // spiBeginTransaction.
+  #define SOFTWARE_SPI  // If the SD card and LCD adapter share the same SPI pins, then software SPI is currently
+                        // needed due to the speed and mode required for communicating with each device being different.
+                        // This requirement can be removed if the SPI access to these devices is updated to use
+                        // spiBeginTransaction.
 #endif
 
 // Onboard SD

Marlin/src/HAL/LPC1768/HAL_SPI.cpp

@@ -60,7 +60,7 @@
 // ------------------------
 // Public functions
 // ------------------------
-#if ENABLED(LPC_SOFTWARE_SPI)
+#if ENABLED(SOFTWARE_SPI)
 
   // Software SPI
 
@@ -161,7 +161,7 @@
     // TODO: Implement this method
   }
 
-#endif // LPC_SOFTWARE_SPI
+#endif // SOFTWARE_SPI
 
 /**
  * @brief Wait until TXE (tx empty) flag is set and BSY (busy) flag unset.
@@ -318,8 +318,16 @@ void SPIClass::dmaSend(void *buf, uint16_t length, bool minc) {
   // Enable DMA
   GPDMA_ChannelCmd(0, ENABLE);
 
+  /*
+   * Observed behaviour on normal data transfer completion (SKR 1.3 board / LPC1768 MCU)
+   *   GPDMA_STAT_INTTC flag is SET
+   *   GPDMA_STAT_INTERR flag is NOT SET
+   *   GPDMA_STAT_RAWINTTC flag is NOT SET
+   *   GPDMA_STAT_RAWINTERR flag is SET
+   */
+
   // Wait for data transfer
-  while (!GPDMA_IntGetStatus(GPDMA_STAT_RAWINTTC, 0) && !GPDMA_IntGetStatus(GPDMA_STAT_RAWINTERR, 0)) { }
+  while (!GPDMA_IntGetStatus(GPDMA_STAT_INTTC, 0) && !GPDMA_IntGetStatus(GPDMA_STAT_INTERR, 0)) {}
 
   // Clear err and int
   GPDMA_ClearIntPending (GPDMA_STATCLR_INTTC, 0);
@@ -333,6 +341,43 @@ void SPIClass::dmaSend(void *buf, uint16_t length, bool minc) {
   SSP_DMACmd(_currentSetting->spi_d, SSP_DMA_TX, DISABLE);
 }
 
+void SPIClass::dmaSendAsync(void *buf, uint16_t length, bool minc) {
+  //TODO: LPC dma can only write 0xFFF bytes at once.
+  GPDMA_Channel_CFG_Type GPDMACfg;
+
+  /* Configure GPDMA channel 0 -------------------------------------------------------------*/
+  /* DMA Channel 0 */
+  GPDMACfg.ChannelNum = 0;
+  // Source memory
+  GPDMACfg.SrcMemAddr = (uint32_t)buf;
+  // Destination memory - Not used
+  GPDMACfg.DstMemAddr = 0;
+  // Transfer size
+  GPDMACfg.TransferSize = length;
+  // Transfer width
+  GPDMACfg.TransferWidth = (_currentSetting->dataSize == DATA_SIZE_16BIT) ? GPDMA_WIDTH_HALFWORD : GPDMA_WIDTH_BYTE;
+  // Transfer type
+  GPDMACfg.TransferType = GPDMA_TRANSFERTYPE_M2P;
+  // Source connection - unused
+  GPDMACfg.SrcConn = 0;
+  // Destination connection
+  GPDMACfg.DstConn = (_currentSetting->spi_d == LPC_SSP0) ? GPDMA_CONN_SSP0_Tx : GPDMA_CONN_SSP1_Tx;
+
+  GPDMACfg.DMALLI = 0;
+
+  // Enable dma on SPI
+  SSP_DMACmd(_currentSetting->spi_d, SSP_DMA_TX, ENABLE);
+
+  // Only increase memory if minc is true
+  GPDMACfg.MemoryIncrease = (minc ? GPDMA_DMACCxControl_SI : 0);
+
+  // Setup channel with given parameter
+  GPDMA_Setup(&GPDMACfg);
+
+  // Enable DMA
+  GPDMA_ChannelCmd(0, ENABLE);
+}
+
 uint16_t SPIClass::read() {
   return SSP_ReceiveData(_currentSetting->spi_d);
 }

Marlin/src/HAL/LPC1768/endstop_interrupts.h

@@ -155,4 +155,37 @@ void setup_endstop_interrupts() {
     #endif
     _ATTACH(K_MIN_PIN);
   #endif
+  #if HAS_U_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(U_MAX_PIN)
+      #error "U_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(U_MAX_PIN);
+  #elif HAS_U_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(U_MIN_PIN)
+      #error "U_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(U_MIN_PIN);
+  #endif
+  #if HAS_V_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(V_MAX_PIN)
+      #error "V_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(V_MAX_PIN);
+  #elif HAS_V_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(V_MIN_PIN)
+      #error "V_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(V_MIN_PIN);
+  #endif
+  #if HAS_W_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(W_MAX_PIN)
+      #error "W_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(W_MAX_PIN);
+  #elif HAS_W_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(W_MIN_PIN)
+      #error "W_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(W_MIN_PIN);
+  #endif
 }

Marlin/src/HAL/LPC1768/inc/Conditionals_LCD.h

@@ -20,7 +20,3 @@
  *
  */
 #pragma once
-
-#if HAS_FSMC_TFT
-  #error "Sorry! FSMC TFT displays are not current available for HAL/LPC1768."
-#endif

Marlin/src/HAL/LPC1768/inc/Conditionals_post.h

@@ -29,6 +29,6 @@
 
 // LPC1768 boards seem to lose steps when saving to EEPROM during print (issue #20785)
 // TODO: Which other boards are incompatible?
-#if defined(MCU_LPC1768) && PRINTCOUNTER_SAVE_INTERVAL > 0
-  #define PRINTCOUNTER_SYNC 1
+#if defined(MCU_LPC1768) && ENABLED(FLASH_EEPROM_EMULATION) && PRINTCOUNTER_SAVE_INTERVAL > 0
+  #define PRINTCOUNTER_SYNC
 #endif

Marlin/src/HAL/LPC1768/inc/SanityCheck.h

@@ -77,6 +77,10 @@ static_assert(!(NUM_SERVOS && ENABLED(FAST_PWM_FAN)), "BLTOUCH and Servos are in
   #endif
 #endif
 
+#if HAS_FSMC_TFT
+  #error "Sorry! FSMC TFT displays are not current available for HAL/LPC1768."
+#endif
+
 static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported on LPC176x.");
 
 /**

Marlin/src/HAL/LPC1768/include/SPI.h

@@ -155,6 +155,7 @@ public:
   void read(uint8_t *buf, uint32_t len);
 
   void dmaSend(void *buf, uint16_t length, bool minc);
+  void dmaSendAsync(void *buf, uint16_t length, bool minc);
 
   /**
    * @brief Sets the number of the SPI peripheral to be used by

Marlin/src/HAL/LPC1768/pinsDebug.h

@@ -29,8 +29,8 @@
  */
 
 #define NUMBER_PINS_TOTAL NUM_DIGITAL_PINS
-#define pwm_details(pin) pin = pin    // do nothing  // print PWM details
-#define pwm_status(pin) false //Print a pin's PWM status. Return true if it's currently a PWM pin.
+#define pwm_details(pin) NOOP // do nothing
+#define pwm_status(pin) false // Print a pin's PWM status. Return true if it's currently a PWM pin.
 #define IS_ANALOG(P) (DIGITAL_PIN_TO_ANALOG_PIN(P) >= 0 ? 1 : 0)
 #define digitalRead_mod(p) extDigitalRead(p)
 #define PRINT_PORT(p)

Marlin/src/HAL/LPC1768/spi_pins.h

@@ -24,10 +24,10 @@
 #include "../../core/macros.h"
 
 #if BOTH(SDSUPPORT, HAS_MARLINUI_U8GLIB) && (LCD_PINS_D4 == SD_SCK_PIN || LCD_PINS_ENABLE == SD_MOSI_PIN || DOGLCD_SCK == SD_SCK_PIN || DOGLCD_MOSI == SD_MOSI_PIN)
-  #define LPC_SOFTWARE_SPI  // If the SD card and LCD adapter share the same SPI pins, then software SPI is currently
-                            // needed due to the speed and mode required for communicating with each device being different.
-                            // This requirement can be removed if the SPI access to these devices is updated to use
-                            // spiBeginTransaction.
+  #define SOFTWARE_SPI  // If the SD card and LCD adapter share the same SPI pins, then software SPI is currently
+                        // needed due to the speed and mode required for communicating with each device being different.
+                        // This requirement can be removed if the SPI access to these devices is updated to use
+                        // spiBeginTransaction.
 #endif
 
 /** onboard SD card */

Marlin/src/HAL/LPC1768/tft/tft_spi.cpp

@@ -26,7 +26,7 @@
 
 #include "tft_spi.h"
 
-SPIClass TFT_SPI::SPIx(1);
+SPIClass TFT_SPI::SPIx(TFT_SPI_DEVICE);
 
 void TFT_SPI::Init() {
   #if PIN_EXISTS(TFT_RESET)
@@ -38,40 +38,10 @@ void TFT_SPI::Init() {
     OUT_WRITE(TFT_BACKLIGHT_PIN, HIGH);
   #endif
 
-  SET_OUTPUT(TFT_DC_PIN);
-  SET_OUTPUT(TFT_CS_PIN);
-  WRITE(TFT_DC_PIN, HIGH);
-  WRITE(TFT_CS_PIN, HIGH);
+  OUT_WRITE(TFT_DC_PIN, HIGH);
+  OUT_WRITE(TFT_CS_PIN, HIGH);
 
-  /**
-   * STM32F1 APB2 = 72MHz, APB1 = 36MHz, max SPI speed of this MCU if 18Mhz
-   * STM32F1 has 3 SPI ports, SPI1 in APB2, SPI2/SPI3 in APB1
-   * so the minimum prescale of SPI1 is DIV4, SPI2/SPI3 is DIV2
-   */
-  #if 0
-    #if SPI_DEVICE == 1
-     #define SPI_CLOCK_MAX SPI_CLOCK_DIV4
-    #else
-     #define SPI_CLOCK_MAX SPI_CLOCK_DIV2
-    #endif
-    uint8_t  clock;
-    uint8_t spiRate = SPI_FULL_SPEED;
-    switch (spiRate) {
-     case SPI_FULL_SPEED:    clock = SPI_CLOCK_MAX ;  break;
-     case SPI_HALF_SPEED:    clock = SPI_CLOCK_DIV4 ; break;
-     case SPI_QUARTER_SPEED: clock = SPI_CLOCK_DIV8 ; break;
-     case SPI_EIGHTH_SPEED:  clock = SPI_CLOCK_DIV16; break;
-     case SPI_SPEED_5:       clock = SPI_CLOCK_DIV32; break;
-     case SPI_SPEED_6:       clock = SPI_CLOCK_DIV64; break;
-     default:                clock = SPI_CLOCK_DIV2;  // Default from the SPI library
-    }
-  #endif
-
-  #if TFT_MISO_PIN == BOARD_SPI1_MISO_PIN
-    SPIx.setModule(1);
-  #elif TFT_MISO_PIN == BOARD_SPI2_MISO_PIN
-    SPIx.setModule(2);
-  #endif
+  SPIx.setModule(TFT_SPI_DEVICE);
   SPIx.setClock(SPI_CLOCK_MAX_TFT);
   SPIx.setBitOrder(MSBFIRST);
   SPIx.setDataMode(SPI_MODE0);
@@ -114,17 +84,62 @@ uint32_t TFT_SPI::ReadID(uint16_t Reg) {
   return data >> 7;
 }
 
-bool TFT_SPI::isBusy() { return false; }
+bool TFT_SPI::isBusy() {
+  #define __IS_DMA_CONFIGURED(__HANDLE__)   ((__HANDLE__)->DMACCSrcAddr != 0)
 
-void TFT_SPI::Abort() { DataTransferEnd(); }
+  // DMA Channel 0 is hardcoded in dmaSendAsync() and dmaSend()
+  if (!__IS_DMA_CONFIGURED(LPC_GPDMACH0)) return false;
 
-void TFT_SPI::Transmit(uint16_t Data) { SPIx.transfer(Data); }
+  if (GPDMA_IntGetStatus(GPDMA_STAT_INTERR, 0)) {
+    // You should not be here - DMA transfer error flag is set
+    // Abort DMA transfer and release SPI
+  }
+  else {
+    // Check if DMA transfer completed flag is set
+    if (!GPDMA_IntGetStatus(GPDMA_STAT_INTTC, 0)) return true;
+    // Check if SPI TX butter is empty and SPI is idle
+    if ((SSP_GetStatus(LPC_SSPx, SSP_STAT_TXFIFO_EMPTY) == RESET) || (SSP_GetStatus(LPC_SSPx, SSP_STAT_BUSY) == SET)) return true;
+  }
+
+  Abort();
+  return false;
+}
+
+void TFT_SPI::Abort() {
+  // DMA Channel 0 is hardcoded in dmaSendAsync() and dmaSend()
+
+  // Disable DMA
+  GPDMA_ChannelCmd(0, DISABLE);
+
+  // Clear ERR and TC
+  GPDMA_ClearIntPending(GPDMA_STATCLR_INTTC, 0);
+  GPDMA_ClearIntPending(GPDMA_STATCLR_INTERR, 0);
+
+  // Disable DMA on SPI
+  SSP_DMACmd(LPC_SSPx, SSP_DMA_TX, DISABLE);
+
+  // Deconfigure DMA Channel 0
+  LPC_GPDMACH0->DMACCControl  = 0U;
+  LPC_GPDMACH0->DMACCConfig   = 0U;
+  LPC_GPDMACH0->DMACCSrcAddr  = 0U;
+  LPC_GPDMACH0->DMACCDestAddr = 0U;
 
-void TFT_SPI::TransmitDMA(uint32_t MemoryIncrease, uint16_t *Data, uint16_t Count) {
-  DataTransferBegin(DATASIZE_16BIT);
-  WRITE(TFT_DC_PIN, HIGH);
-  SPIx.dmaSend(Data, Count, MemoryIncrease);
   DataTransferEnd();
 }
 
+void TFT_SPI::Transmit(uint16_t Data) { SPIx.transfer(Data); }
+
+void TFT_SPI::Transmit(uint32_t MemoryIncrease, uint16_t *Data, uint16_t Count) {
+  DataTransferBegin(DATASIZE_16BIT);
+  SPIx.dmaSend(Data, Count, MemoryIncrease);
+  Abort();
+}
+
+void TFT_SPI::TransmitDMA(uint32_t MemoryIncrease, uint16_t *Data, uint16_t Count) {
+  DataTransferBegin(DATASIZE_16BIT);
+  SPIx.dmaSendAsync(Data, Count, MemoryIncrease);
+
+  TERN_(TFT_SHARED_SPI, while (isBusy()));
+}
+
 #endif // HAS_SPI_TFT

Marlin/src/HAL/LPC1768/tft/tft_spi.h

@@ -27,6 +27,18 @@
 #include <lpc17xx_ssp.h>
 // #include <lpc17xx_gpdma.h>
 
+#define IS_SPI(N) (BOARD_NR_SPI >= N && (TFT_SCK_PIN == BOARD_SPI##N##_SCK_PIN) && (TFT_MOSI_PIN == BOARD_SPI##N##_MOSI_PIN) && (TFT_MISO_PIN == BOARD_SPI##N##_MISO_PIN))
+#if IS_SPI(1)
+  #define TFT_SPI_DEVICE  1
+  #define LPC_SSPx  LPC_SSP0
+#elif IS_SPI(2)
+  #define TFT_SPI_DEVICE  2
+  #define LPC_SSPx  LPC_SSP1
+#else
+  #error "Invalid TFT SPI configuration."
+#endif
+#undef IS_SPI
+
 #ifndef LCD_READ_ID
   #define LCD_READ_ID  0x04   // Read display identification information (0xD3 on ILI9341)
 #endif
@@ -34,17 +46,19 @@
   #define LCD_READ_ID4 0xD3   // Read display identification information (0xD3 on ILI9341)
 #endif
 
-#define DATASIZE_8BIT    SSP_DATABIT_8
-#define DATASIZE_16BIT   SSP_DATABIT_16
-#define TFT_IO_DRIVER TFT_SPI
+#define DATASIZE_8BIT     SSP_DATABIT_8
+#define DATASIZE_16BIT    SSP_DATABIT_16
+#define TFT_IO_DRIVER     TFT_SPI
+#define DMA_MAX_SIZE      0xFFF
 
-#define DMA_MINC_ENABLE 1
-#define DMA_MINC_DISABLE 0
+#define DMA_MINC_ENABLE   1
+#define DMA_MINC_DISABLE  0
 
 class TFT_SPI {
 private:
   static uint32_t ReadID(uint16_t Reg);
   static void Transmit(uint16_t Data);
+  static void Transmit(uint32_t MemoryIncrease, uint16_t *Data, uint16_t Count);
   static void TransmitDMA(uint32_t MemoryIncrease, uint16_t *Data, uint16_t Count);
 
 public:
@@ -56,22 +70,20 @@ public:
   static void Abort();
 
   static void DataTransferBegin(uint16_t DataWidth = DATASIZE_16BIT);
-  static void DataTransferEnd() { OUT_WRITE(TFT_CS_PIN, HIGH); SPIx.end(); };
+  static void DataTransferEnd() { WRITE(TFT_CS_PIN, HIGH); SSP_Cmd(LPC_SSPx, DISABLE); };
   static void DataTransferAbort();
 
   static void WriteData(uint16_t Data) { Transmit(Data); }
-  static void WriteReg(uint16_t Reg) { OUT_WRITE(TFT_A0_PIN, LOW); Transmit(Reg); OUT_WRITE(TFT_A0_PIN, HIGH); }
+  static void WriteReg(uint16_t Reg) { WRITE(TFT_DC_PIN, LOW); Transmit(Reg); WRITE(TFT_DC_PIN, HIGH); }
 
-  static void WriteSequence(uint16_t *Data, uint16_t Count) { TransmitDMA(DMA_MINC_ENABLE, Data, Count); }
-  // static void WriteMultiple(uint16_t Color, uint16_t Count) { static uint16_t Data; Data = Color; TransmitDMA(DMA_MINC_DISABLE, &Data, Count); }
+  static void WriteSequence_DMA(uint16_t *Data, uint16_t Count) { TransmitDMA(DMA_MINC_ENABLE, Data, Count); }
+  static void WriteMultiple_DMA(uint16_t Color, uint16_t Count) { static uint16_t Data; Data = Color; TransmitDMA(DMA_MINC_DISABLE, &Data, Count); }
+
+  static void WriteSequence(uint16_t *Data, uint16_t Count) { Transmit(DMA_MINC_ENABLE, Data, Count); }
   static void WriteMultiple(uint16_t Color, uint32_t Count) {
-    static uint16_t Data; Data = Color;
-    //LPC dma can only write 0xFFF bytes at once.
-    #define MAX_DMA_SIZE (0xFFF - 1)
     while (Count > 0) {
-      TransmitDMA(DMA_MINC_DISABLE, &Data, Count > MAX_DMA_SIZE ? MAX_DMA_SIZE : Count);
-      Count = Count > MAX_DMA_SIZE ? Count - MAX_DMA_SIZE : 0;
+      Transmit(DMA_MINC_DISABLE, &Color, Count > DMA_MAX_SIZE ? DMA_MAX_SIZE : Count);
+      Count = Count > DMA_MAX_SIZE ? Count - DMA_MAX_SIZE : 0;
     }
-    #undef MAX_DMA_SIZE
   }
 };

Marlin/src/HAL/LPC1768/tft/xpt2046.cpp

@@ -44,9 +44,11 @@ uint16_t delta(uint16_t a, uint16_t b) { return a > b ? a - b : b - a; }
 #endif
 
 void XPT2046::Init() {
-  SET_INPUT(TOUCH_MISO_PIN);
-  SET_OUTPUT(TOUCH_MOSI_PIN);
-  SET_OUTPUT(TOUCH_SCK_PIN);
+  #if DISABLED(TOUCH_BUTTONS_HW_SPI)
+    SET_INPUT(TOUCH_MISO_PIN);
+    SET_OUTPUT(TOUCH_MOSI_PIN);
+    SET_OUTPUT(TOUCH_SCK_PIN);
+  #endif
   OUT_WRITE(TOUCH_CS_PIN, HIGH);
 
   #if PIN_EXISTS(TOUCH_INT)

Marlin/src/HAL/LPC1768/upload_extra_script.py

@@ -9,119 +9,127 @@ from __future__ import print_function
 import pioutil
 if pioutil.is_pio_build():
 
-	target_filename = "FIRMWARE.CUR"
-	target_drive = "REARM"
+    target_filename = "FIRMWARE.CUR"
+    target_drive = "REARM"
 
-	import os,getpass,platform
+    import platform
 
-	current_OS = platform.system()
-	Import("env")
+    current_OS = platform.system()
+    Import("env")
 
-	def print_error(e):
-		print('\nUnable to find destination disk (%s)\n' \
-			  'Please select it in platformio.ini using the upload_port keyword ' \
-			  '(https://docs.platformio.org/en/latest/projectconf/section_env_upload.html) ' \
-			  'or copy the firmware (.pio/build/%s/firmware.bin) manually to the appropriate disk\n' \
-			  %(e, env.get('PIOENV')))
+    def print_error(e):
+        print('\nUnable to find destination disk (%s)\n' \
+              'Please select it in platformio.ini using the upload_port keyword ' \
+              '(https://docs.platformio.org/en/latest/projectconf/section_env_upload.html) ' \
+              'or copy the firmware (.pio/build/%s/firmware.bin) manually to the appropriate disk\n' \
+              %(e, env.get('PIOENV')))
 
-	def before_upload(source, target, env):
-		try:
-			#
-			# Find a disk for upload
-			#
-			upload_disk = 'Disk not found'
-			target_file_found = False
-			target_drive_found = False
-			if current_OS == 'Windows':
-				#
-				# platformio.ini will accept this for a Windows upload port designation: 'upload_port = L:'
-				#   Windows - doesn't care about the disk's name, only cares about the drive letter
-				import subprocess,string
-				from ctypes import windll
+    def before_upload(source, target, env):
+        try:
+            from pathlib import Path
+            #
+            # Find a disk for upload
+            #
+            upload_disk = 'Disk not found'
+            target_file_found = False
+            target_drive_found = False
+            if current_OS == 'Windows':
+                #
+                # platformio.ini will accept this for a Windows upload port designation: 'upload_port = L:'
+                #   Windows - doesn't care about the disk's name, only cares about the drive letter
+                import subprocess,string
+                from ctypes import windll
+                from pathlib import PureWindowsPath
 
-				# getting list of drives
-				# https://stackoverflow.com/questions/827371/is-there-a-way-to-list-all-the-available-drive-letters-in-python
-				drives = []
-				bitmask = windll.kernel32.GetLogicalDrives()
-				for letter in string.ascii_uppercase:
-					if bitmask & 1:
-						drives.append(letter)
-					bitmask >>= 1
+                # getting list of drives
+                # https://stackoverflow.com/questions/827371/is-there-a-way-to-list-all-the-available-drive-letters-in-python
+                drives = []
+                bitmask = windll.kernel32.GetLogicalDrives()
+                for letter in string.ascii_uppercase:
+                    if bitmask & 1:
+                        drives.append(letter)
+                    bitmask >>= 1
 
-				for drive in drives:
-					final_drive_name = drive + ':\\'
-					# print ('disc check: {}'.format(final_drive_name))
-					try:
-						volume_info = str(subprocess.check_output('cmd /C dir ' + final_drive_name, stderr=subprocess.STDOUT))
-					except Exception as e:
-						print ('error:{}'.format(e))
-						continue
-					else:
-						if target_drive in volume_info and not target_file_found:  # set upload if not found target file yet
-							target_drive_found = True
-							upload_disk = final_drive_name
-						if target_filename in volume_info:
-							if not target_file_found:
-								upload_disk = final_drive_name
-							target_file_found = True
+                for drive in drives:
+                    final_drive_name = drive + ':'
+                    # print ('disc check: {}'.format(final_drive_name))
+                    try:
+                        volume_info = str(subprocess.check_output('cmd /C dir ' + final_drive_name, stderr=subprocess.STDOUT))
+                    except Exception as e:
+                        print ('error:{}'.format(e))
+                        continue
+                    else:
+                        if target_drive in volume_info and not target_file_found:  # set upload if not found target file yet
+                            target_drive_found = True
+                            upload_disk = PureWindowsPath(final_drive_name)
+                        if target_filename in volume_info:
+                            if not target_file_found:
+                                upload_disk = PureWindowsPath(final_drive_name)
+                            target_file_found = True
 
-			elif current_OS == 'Linux':
-				#
-				# platformio.ini will accept this for a Linux upload port designation: 'upload_port = /media/media_name/drive'
-				#
-				drives = os.listdir(os.path.join(os.sep, 'media', getpass.getuser()))
-				if target_drive in drives:  # If target drive is found, use it.
-					target_drive_found = True
-					upload_disk = os.path.join(os.sep, 'media', getpass.getuser(), target_drive) + os.sep
-				else:
-					for drive in drives:
-						try:
-							files = os.listdir(os.path.join(os.sep, 'media', getpass.getuser(), drive))
-						except:
-							continue
-						else:
-							if target_filename in files:
-								upload_disk = os.path.join(os.sep, 'media', getpass.getuser(), drive) + os.sep
-								target_file_found = True
-								break
-				#
-				# set upload_port to drive if found
-				#
+            elif current_OS == 'Linux':
+                #
+                # platformio.ini will accept this for a Linux upload port designation: 'upload_port = /media/media_name/drive'
+                #
+                import getpass
+                user = getpass.getuser()
+                mpath = Path('/media', user)
+                drives = [ x for x in mpath.iterdir() if x.is_dir() ]
+                if target_drive in drives:  # If target drive is found, use it.
+                    target_drive_found = True
+                    upload_disk = mpath / target_drive
+                else:
+                    for drive in drives:
+                        try:
+                            fpath = mpath / drive
+                            filenames = [ x.name for x in fpath.iterdir() if x.is_file() ]
+                        except:
+                            continue
+                        else:
+                            if target_filename in filenames:
+                                upload_disk = mpath / drive
+                                target_file_found = True
+                                break
+                #
+                # set upload_port to drive if found
+                #
 
-				if target_file_found or target_drive_found:
-					env.Replace(
-						UPLOAD_FLAGS="-P$UPLOAD_PORT"
-					)
+                if target_file_found or target_drive_found:
+                    env.Replace(
+                        UPLOAD_FLAGS="-P$UPLOAD_PORT"
+                    )
 
-			elif current_OS == 'Darwin':  # MAC
-				#
-				# platformio.ini will accept this for a OSX upload port designation: 'upload_port = /media/media_name/drive'
-				#
-				drives = os.listdir('/Volumes')  # human readable names
-				if target_drive in drives and not target_file_found:  # set upload if not found target file yet
-					target_drive_found = True
-					upload_disk = '/Volumes/' + target_drive + '/'
-				for drive in drives:
-					try:
-						filenames = os.listdir('/Volumes/' + drive + '/')   # will get an error if the drive is protected
-					except:
-						continue
-					else:
-						if target_filename in filenames:
-							if not target_file_found:
-								upload_disk = '/Volumes/' + drive + '/'
-							target_file_found = True
+            elif current_OS == 'Darwin':  # MAC
+                #
+                # platformio.ini will accept this for a OSX upload port designation: 'upload_port = /media/media_name/drive'
+                #
+                dpath = Path('/Volumes')  # human readable names
+                drives = [ x for x in dpath.iterdir() if x.is_dir() ]
+                if target_drive in drives and not target_file_found:  # set upload if not found target file yet
+                    target_drive_found = True
+                    upload_disk = dpath / target_drive
+                for drive in drives:
+                    try:
+                        fpath = dpath / drive   # will get an error if the drive is protected
+                        filenames = [ x.name for x in fpath.iterdir() if x.is_file() ]
+                    except:
+                        continue
+                    else:
+                        if target_filename in filenames:
+                            upload_disk = dpath / drive
+                            target_file_found = True
+                            break
 
-			#
-			# Set upload_port to drive if found
-			#
-			if target_file_found or target_drive_found:
-				env.Replace(UPLOAD_PORT=upload_disk)
-				print('\nUpload disk: ', upload_disk, '\n')
-			else:
-				print_error('Autodetect Error')
+            #
+            # Set upload_port to drive if found
+            #
+            if target_file_found or target_drive_found:
+                env.Replace(UPLOAD_PORT=str(upload_disk))
+                print('\nUpload disk: ', upload_disk, '\n')
+            else:
+                print_error('Autodetect Error')
 
-		except Exception as e:
-			print_error(str(e))
+        except Exception as e:
+            print_error(str(e))
 
-	env.AddPreAction("upload", before_upload)
+    env.AddPreAction("upload", before_upload)

Marlin/src/HAL/NATIVE_SIM/HAL.h

@@ -208,8 +208,8 @@ public:
   MarlinHAL() {}
 
   // Watchdog
-  static void watchdog_init()    IF_DISABLED(USE_WATCHDOG, {});
-  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_init();
+  static void watchdog_refresh();
 
   static void init() {}        // Called early in setup()
   static void init_board() {}  // Called less early in setup()

Marlin/src/HAL/NATIVE_SIM/fastio.h

@@ -44,7 +44,7 @@
  *
  * Now you can simply SET_OUTPUT(STEP); WRITE(STEP, HIGH); WRITE(STEP, LOW);
  *
- * Why double up on these macros? see http://gcc.gnu.org/onlinedocs/cpp/Stringification.html
+ * Why double up on these macros? see https://gcc.gnu.org/onlinedocs/cpp/Stringification.html
  */
 
 /// Read a pin

Marlin/src/HAL/NATIVE_SIM/inc/SanityCheck.h

@@ -31,7 +31,7 @@
 #endif
 
 #if ENABLED(FAST_PWM_FAN) || SPINDLE_LASER_FREQUENCY
-  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported on LINUX."
+  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported for HAL/LINUX."
 #endif
 
 #if HAS_TMC_SW_SERIAL

Marlin/src/HAL/NATIVE_SIM/pinsDebug.h

@@ -27,8 +27,8 @@
  */
 
 #define NUMBER_PINS_TOTAL NUM_DIGITAL_PINS
-#define pwm_details(pin) pin = pin    // do nothing  // print PWM details
-#define pwm_status(pin) false //Print a pin's PWM status. Return true if it's currently a PWM pin.
+#define pwm_details(pin) NOOP // do nothing
+#define pwm_status(pin) false // Print a pin's PWM status. Return true if it's currently a PWM pin.
 #define IS_ANALOG(P) (DIGITAL_PIN_TO_ANALOG_PIN(P) >= 0 ? 1 : 0)
 #define digitalRead_mod(p)  digitalRead(p)
 #define PRINT_PORT(p)

Marlin/src/HAL/NATIVE_SIM/spi_pins.h

@@ -25,7 +25,7 @@
 #include "../../inc/MarlinConfigPre.h"
 
 #if BOTH(HAS_MARLINUI_U8GLIB, SDSUPPORT) && (LCD_PINS_D4 == SD_SCK_PIN || LCD_PINS_ENABLE == SD_MOSI_PIN || DOGLCD_SCK == SD_SCK_PIN || DOGLCD_MOSI == SD_MOSI_PIN)
-  #define LPC_SOFTWARE_SPI  // If the SD card and LCD adapter share the same SPI pins, then software SPI is currently
+  #define SOFTWARE_SPI      // If the SD card and LCD adapter share the same SPI pins, then software SPI is currently
                             // needed due to the speed and mode required for communicating with each device being different.
                             // This requirement can be removed if the SPI access to these devices is updated to use
                             // spiBeginTransaction.

Marlin/src/HAL/NATIVE_SIM/tft/xpt2046.h

@@ -51,7 +51,7 @@ enum XPTCoordinate : uint8_t {
   XPT2046_Z2 = 0x40 | XPT2046_CONTROL | XPT2046_DFR_MODE,
 };
 
-#if !defined(XPT2046_Z1_THRESHOLD)
+#ifndef XPT2046_Z1_THRESHOLD
   #define XPT2046_Z1_THRESHOLD 10
 #endif
 

Marlin/src/HAL/NATIVE_SIM/u8g/LCD_I2C_routines.h

@@ -34,4 +34,3 @@ void u8g_i2c_stop();
 #ifdef __cplusplus
   }
 #endif
-

Marlin/src/HAL/NATIVE_SIM/u8g/LCD_defines.h

@@ -40,5 +40,3 @@ uint8_t u8g_com_ST7920_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void
 #define U8G_COM_T6963 u8g_com_null_fn
 #define U8G_COM_FAST_PARALLEL u8g_com_null_fn
 #define U8G_COM_UC_I2C u8g_com_null_fn
-
-

Marlin/src/HAL/NATIVE_SIM/u8g/u8g_com_st7920_sw_spi.cpp

@@ -168,4 +168,4 @@ uint8_t u8g_com_ST7920_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void
 #endif
 
 #endif // IS_U8GLIB_ST7920
-#endif // TARGET_LPC1768
+#endif // __PLAT_NATIVE_SIM__

Marlin/src/HAL/SAMD21/HAL.cpp

@@ -0,0 +1,212 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#ifdef __SAMD21__
+
+#include "../../inc/MarlinConfig.h"
+
+#include <wiring_private.h>
+
+#if USING_HW_SERIALUSB
+  DefaultSerial1 MSerialUSB(false, SerialUSB);
+#endif
+#if USING_HW_SERIAL0
+  DefaultSerial2 MSerial1(false, Serial1);
+#endif
+#if USING_HW_SERIAL1
+  DefaultSerial3 MSerial2(false, Serial2);
+#endif
+
+
+
+#define WDT_CONFIG_PER_7_Val 0x9u
+#define WDT_CONFIG_PER_Pos 0
+#define WDT_CONFIG_PER_7 (WDT_CONFIG_PER_7_Val << WDT_CONFIG_PER_Pos)
+
+#if ENABLED(USE_WATCHDOG)
+
+  #define WDT_TIMEOUT_REG TERN(WATCHDOG_DURATION_8S, WDT_CONFIG_PER_CYC8192, WDT_CONFIG_PER_CYC4096) // 4 or 8 second timeout
+
+  void MarlinHAL::watchdog_init() {
+       // Set up the generic clock (GCLK2) used to clock the watchdog timer at 1.024kHz
+    GCLK->GENDIV.reg = GCLK_GENDIV_DIV(4) |            // Divide the 32.768kHz clock source by divisor 32, where 2^(4 + 1): 32.768kHz/32=1.024kHz
+                      GCLK_GENDIV_ID(2);              // Select Generic Clock (GCLK) 2
+    while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization
+
+    REG_GCLK_GENCTRL =  GCLK_GENCTRL_DIVSEL |         // Set to divide by 2^(GCLK_GENDIV_DIV(4) + 1)
+                        GCLK_GENCTRL_IDC |            // Set the duty cycle to 50/50 HIGH/LOW
+                        GCLK_GENCTRL_GENEN |          // Enable GCLK2
+                        GCLK_GENCTRL_SRC_OSCULP32K |  // Set the clock source to the ultra low power oscillator (OSCULP32K)
+                        GCLK_GENCTRL_ID(2);           // Select GCLK2
+    while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization
+
+    // Feed GCLK2 to WDT (Watchdog Timer)
+    REG_GCLK_CLKCTRL =  GCLK_CLKCTRL_CLKEN |          // Enable GCLK2 to the WDT
+                        GCLK_CLKCTRL_GEN_GCLK2 |      // Select GCLK2
+                        GCLK_CLKCTRL_ID_WDT;          // Feed the GCLK2 to the WDT
+    while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization
+
+    WDT->CONFIG.bit.PER = WDT_CONFIG_PER_7;                // Set the WDT reset timeout to 4 seconds
+    while (WDT->STATUS.bit.SYNCBUSY);                 // Wait for synchronization
+    REG_WDT_CTRL = WDT_CTRL_ENABLE;                   // Enable the WDT in normal mode
+    while (WDT->STATUS.bit.SYNCBUSY);                 // Wait for synchronization
+  }
+
+  // Reset watchdog. MUST be called at least every 4 seconds after the
+  // first watchdog_init or SAMD will go into emergency procedures.
+  void MarlinHAL::watchdog_refresh() {
+    WDT->CLEAR.reg = WDT_CLEAR_CLEAR_KEY;
+    while (WDT->STATUS.bit.SYNCBUSY);
+  }
+
+#endif
+
+// ------------------------
+// Types
+// ------------------------
+
+// ------------------------
+// Private Variables
+// ------------------------
+
+// ------------------------
+// Private functions
+// ------------------------
+
+void MarlinHAL::dma_init() {}
+
+// ------------------------
+// Public functions
+// ------------------------
+
+// HAL initialization task
+void MarlinHAL::init() {
+  TERN_(DMA_IS_REQUIRED, dma_init());
+  #if ENABLED(SDSUPPORT)
+    #if HAS_SD_DETECT && SD_CONNECTION_IS(ONBOARD)
+      SET_INPUT_PULLUP(SD_DETECT_PIN);
+    #endif
+    OUT_WRITE(SDSS, HIGH);  // Try to set SDSS inactive before any other SPI users start up
+  #endif
+}
+
+#pragma push_macro("WDT")
+#undef WDT    // Required to be able to use '.bit.WDT'. Compiler wrongly replace struct field with WDT define
+uint8_t MarlinHAL::get_reset_source() {
+
+  return 0;
+}
+#pragma pop_macro("WDT")
+
+void MarlinHAL::reboot() { NVIC_SystemReset(); }
+
+extern "C" {
+  void * _sbrk(int incr);
+  extern unsigned int __bss_end__; // end of bss section
+}
+
+// Return free memory between end of heap (or end bss) and whatever is current
+int freeMemory() {
+  int free_memory, heap_end = (int)_sbrk(0);
+  return (int)&free_memory - (heap_end ?: (int)&__bss_end__);
+}
+
+// ------------------------
+// ADC
+// ------------------------
+
+uint16_t MarlinHAL::adc_result;
+
+void MarlinHAL::adc_init() {
+  /* thanks to https://www.eevblog.com/forum/microcontrollers/samd21g18-adc-with-resrdy-interrupts-only-reads-once-or-twice/ */
+
+  ADC->CTRLA.bit.ENABLE = false;
+  while(ADC->STATUS.bit.SYNCBUSY);
+
+  // load chip corrections
+  uint32_t bias = (*((uint32_t *) ADC_FUSES_BIASCAL_ADDR) & ADC_FUSES_BIASCAL_Msk) >> ADC_FUSES_BIASCAL_Pos;
+  uint32_t linearity = (*((uint32_t *) ADC_FUSES_LINEARITY_0_ADDR) & ADC_FUSES_LINEARITY_0_Msk) >> ADC_FUSES_LINEARITY_0_Pos;
+  linearity |= ((*((uint32_t *) ADC_FUSES_LINEARITY_1_ADDR) & ADC_FUSES_LINEARITY_1_Msk) >> ADC_FUSES_LINEARITY_1_Pos) << 5;
+
+  /* Wait for bus synchronization. */
+  while (ADC->STATUS.bit.SYNCBUSY) {};
+
+  ADC->CALIB.reg = ADC_CALIB_BIAS_CAL(bias) | ADC_CALIB_LINEARITY_CAL(linearity);
+
+  /* Wait for bus synchronization. */
+  while (ADC->STATUS.bit.SYNCBUSY) {};
+
+  ADC->CTRLA.bit.SWRST = true;
+  while(ADC->STATUS.bit.SYNCBUSY);
+
+  ADC->REFCTRL.reg = ADC_REFCTRL_REFSEL_INTVCC1;
+  ADC->AVGCTRL.reg = ADC_AVGCTRL_SAMPLENUM_32| ADC_AVGCTRL_ADJRES(4);;
+
+
+  ADC->CTRLB.reg = ADC_CTRLB_PRESCALER_DIV128 |
+                 ADC_CTRLB_RESSEL_16BIT |
+                 ADC_CTRLB_FREERUN;
+  while(ADC->STATUS.bit.SYNCBUSY);
+
+  ADC->SAMPCTRL.bit.SAMPLEN = 0x00;
+  while(ADC->STATUS.bit.SYNCBUSY);
+
+  ADC->INPUTCTRL.reg =  ADC_INPUTCTRL_INPUTSCAN(HAL_ADC_AIN_LEN) // scan  (INPUTSCAN + NUM_EXTUDERS - 1) pins
+  | ADC_INPUTCTRL_GAIN_DIV2  |ADC_INPUTCTRL_MUXNEG_GND| HAL_ADC_AIN_START ;  /* set to first AIN */
+
+  while(ADC->STATUS.bit.SYNCBUSY);
+
+  ADC->INTENSET.reg |= ADC_INTENSET_RESRDY; // enable Result Ready ADC interrupts
+  while (ADC->STATUS.bit.SYNCBUSY);
+
+  NVIC_EnableIRQ(ADC_IRQn); // enable ADC interrupts
+
+  NVIC_SetPriority(ADC_IRQn, 3);
+
+  ADC->CTRLA.bit.ENABLE = true;
+}
+
+volatile uint32_t adc_results[HAL_ADC_AIN_NUM_SENSORS];
+
+void ADC_Handler() {
+  while(ADC->STATUS.bit.SYNCBUSY == 1);
+  int pos = ADC->INPUTCTRL.bit.INPUTOFFSET;
+
+  adc_results[pos] = ADC->RESULT.reg; /* Read the value. */
+  ADC->INTFLAG.reg = ADC_INTENSET_RESRDY; /* Clear the data ready flag. */
+}
+
+void MarlinHAL::adc_start(const pin_t pin) {
+  /* due to the way INPUTOFFSET works, the last sensor is the first position in the array
+    and we want the ADC_handler interrupt to be as simple possible, so we do the calculation here.
+  */
+  unsigned int pos = PIN_TO_INPUTCTRL(pin) - HAL_ADC_AIN_START + 1;
+  if (pos == HAL_ADC_AIN_NUM_SENSORS) pos = 0;
+  adc_result = adc_results[pos]; // 16-bit resolution
+  //adc_result = 0xFFFF;
+}
+
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/HAL.h

@@ -0,0 +1,223 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+#define CPU_32_BIT
+
+#include "../shared/Marduino.h"
+#include "../shared/math_32bit.h"
+#include "../shared/HAL_SPI.h"
+#include "fastio.h"
+
+// ------------------------
+// Serial ports
+// ------------------------
+#include "../../core/serial_hook.h"
+typedef ForwardSerial1Class< decltype(SerialUSB) > DefaultSerial1;
+extern DefaultSerial1 MSerialUSB;
+
+// Serial ports
+typedef ForwardSerial1Class< decltype(Serial1) > DefaultSerial2;
+typedef ForwardSerial1Class< decltype(Serial2) > DefaultSerial3;
+
+extern DefaultSerial2 MSerial0;
+extern DefaultSerial3 MSerial1;
+
+
+#define __MSERIAL(X) MSerial##X
+#define _MSERIAL(X) __MSERIAL(X)
+#define MSERIAL(X) _MSERIAL(INCREMENT(X))
+
+#if WITHIN(SERIAL_PORT, 0, 1)
+  #define MYSERIAL1 MSERIAL(SERIAL_PORT)
+#elif SERIAL_PORT == -1
+  #define MYSERIAL1 MSerialUSB
+#else
+  #error "SERIAL_PORT must be -1 (Native USB only)."
+#endif
+
+#ifdef SERIAL_PORT_2
+  #if WITHIN(SERIAL_PORT_2, 0, 1)
+    #define MYSERIAL2 MSERIAL(SERIAL_PORT)
+  #elif SERIAL_PORT_2 == -1
+    #define MYSERIAL2 MSerialUSB
+  #else
+    #error "SERIAL_PORT_2 must be -1 (Native USB only)."
+  #endif
+#endif
+
+#ifdef MMU2_SERIAL_PORT
+  #if WITHIN(MMU2_SERIAL_PORT, 0, 1)
+    #define MMU2_SERIAL MSERIAL(SERIAL_PORT)
+  #elif MMU2_SERIAL_PORT == -1
+    #define MMU2_SERIAL MSerialUSB
+  #else
+    #error "MMU2_SERIAL_PORT must be -1 (Native USB only)."
+  #endif
+#endif
+
+#ifdef LCD_SERIAL_PORT
+  #if WITHIN(LCD_SERIAL_PORT, 0, 1)
+    #define LCD_SERIAL MSERIAL(SERIAL_PORT)
+  #elif LCD_SERIAL_PORT == -1
+    #define LCD_SERIAL MSerialUSB
+  #else
+    #error "LCD_SERIAL_PORT must be -1 (Native USB only)."
+  #endif
+#endif
+
+typedef int8_t pin_t;
+
+#define SHARED_SERVOS HAS_SERVOS  // Use shared/servos.cpp
+
+class Servo;
+typedef Servo hal_servo_t;
+
+//
+// Interrupts
+//
+#define CRITICAL_SECTION_START()  const bool irqon = !__get_PRIMASK(); __disable_irq()
+#define CRITICAL_SECTION_END()    if (irqon) __enable_irq()
+
+#define cli() __disable_irq() // Disable interrupts
+#define sei() __enable_irq()  // Enable interrupts
+
+//
+// ADC
+//
+
+#define HAL_ADC_FILTERED     1     // Disable Marlin's oversampling. The HAL filters ADC values.
+#define HAL_ADC_VREF         3.3
+#define HAL_ADC_RESOLUTION   12
+#define HAL_ADC_AIN_START ADC_INPUTCTRL_MUXPOS_PIN3
+#define HAL_ADC_AIN_NUM_SENSORS 3
+#define HAL_ADC_AIN_LEN HAL_ADC_AIN_NUM_SENSORS-1
+
+//
+// Pin Mapping for M42, M43, M226
+//
+#define GET_PIN_MAP_PIN(index) index
+#define GET_PIN_MAP_INDEX(pin) pin
+#define PARSED_PIN_INDEX(code, dval) parser.intval(code, dval)
+
+//
+// Tone
+//
+void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration=0);
+void noTone(const pin_t _pin);
+
+// ------------------------
+// Class Utilities
+// ------------------------
+
+#pragma GCC diagnostic push
+#if GCC_VERSION <= 50000
+  #pragma GCC diagnostic ignored "-Wunused-function"
+#endif
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+char *dtostrf(double __val, signed char __width, unsigned char __prec, char *__s);
+
+extern "C" int freeMemory();
+
+#ifdef __cplusplus
+  }
+#endif
+
+#pragma GCC diagnostic pop
+
+// ------------------------
+// MarlinHAL Class
+// ------------------------
+
+class MarlinHAL {
+public:
+
+  // Earliest possible init, before setup()
+  MarlinHAL() {}
+
+  // Watchdog
+  static void watchdog_init()    IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+
+  static void init();          // Called early in setup()
+  static void init_board() {}  // Called less early in setup()
+  static void reboot();        // Restart the firmware from 0x0
+
+  // Interrupts
+  static bool isr_state() { return !__get_PRIMASK(); }
+  static void isr_on()  { sei(); }
+  static void isr_off() { cli(); }
+
+  static void delay_ms(const int ms) { delay(ms); }
+
+  // Tasks, called from idle()
+  static void idletask() {}
+
+  // Reset
+  static uint8_t get_reset_source();
+  static void clear_reset_source() {}
+
+  // Free SRAM
+  static int freeMemory() { return ::freeMemory(); }
+
+  //
+  // ADC Methods
+  //
+
+  static uint16_t adc_result;
+
+  // Called by Temperature::init once at startup
+  static void adc_init();
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const uint8_t ch) {}
+
+  // Begin ADC sampling on the given pin. Called from Temperature::isr!
+  static void adc_start(const pin_t pin);
+
+  // Is the ADC ready for reading?
+  static bool adc_ready() { return true; }
+
+  // The current value of the ADC register
+  static uint16_t adc_value() { return adc_result; }
+
+  /**
+   * Set the PWM duty cycle for the pin to the given value.
+   * No option to invert the duty cycle [default = false]
+   * No option to change the scale of the provided value to enable finer PWM duty control [default = 255]
+   */
+  static void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t=255, const bool=false) {
+    analogWrite(pin, v);
+  }
+
+private:
+  static void dma_init();
+};

Marlin/src/HAL/SAMD21/HAL_SPI.cpp

@@ -0,0 +1,148 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+/**
+ * Hardware and software SPI implementations are included in this file.
+ *
+ * Control of the slave select pin(s) is handled by the calling routines and
+ * SAMD21 let hardware SPI handling to remove SS from its logic.
+ */
+
+#ifdef __SAMD21__
+
+// --------------------------------------------------------------------------
+// Includes
+// --------------------------------------------------------------------------
+
+#include "../../inc/MarlinConfig.h"
+#include <SPI.h>
+
+// --------------------------------------------------------------------------
+// Public functions
+// --------------------------------------------------------------------------
+
+#if EITHER(SOFTWARE_SPI, FORCE_SOFT_SPI)
+
+  // ------------------------
+  // Software SPI
+  // ------------------------
+  #error "Software SPI not supported for SAMD21. Use Hardware SPI."
+
+#else // !SOFTWARE_SPI
+
+  static SPISettings spiConfig;
+
+  // ------------------------
+  // Hardware SPI
+  // ------------------------
+  void spiBegin() {
+    spiInit(SPI_HALF_SPEED);
+  }
+
+  void spiInit(uint8_t spiRate) {
+    // Use Marlin datarates
+    uint32_t clock;
+    switch (spiRate) {
+      case SPI_FULL_SPEED:      clock = 8000000; break;
+      case SPI_HALF_SPEED:      clock = 4000000; break;
+      case SPI_QUARTER_SPEED:   clock = 2000000; break;
+      case SPI_EIGHTH_SPEED:    clock = 1000000; break;
+      case SPI_SIXTEENTH_SPEED: clock =  500000; break;
+      case SPI_SPEED_5:         clock =  250000; break;
+      case SPI_SPEED_6:         clock =  125000; break;
+      default:                  clock = 4000000; break; // Default from the SPI library
+    }
+    spiConfig = SPISettings(clock, MSBFIRST, SPI_MODE0);
+    SPI.begin();
+  }
+
+  /**
+   * @brief  Receives a single byte from the SPI port.
+   *
+   * @return Byte received
+   *
+   * @details
+   */
+  uint8_t spiRec() {
+    SPI.beginTransaction(spiConfig);
+    uint8_t returnByte = SPI.transfer(0xFF);
+    SPI.endTransaction();
+    return returnByte;
+  }
+
+  /**
+   * @brief  Receives a number of bytes from the SPI port to a buffer
+   *
+   * @param  buf   Pointer to starting address of buffer to write to.
+   * @param  nbyte Number of bytes to receive.
+   * @return Nothing
+   */
+  void spiRead(uint8_t *buf, uint16_t nbyte) {
+    if (nbyte == 0) return;
+    memset(buf, 0xFF, nbyte);
+
+    SPI.beginTransaction(spiConfig);
+    SPI.transfer(buf, nbyte);
+    SPI.endTransaction();
+
+  }
+
+  /**
+   * @brief  Sends a single byte on SPI port
+   *
+   * @param  b Byte to send
+   *
+   * @details
+   */
+  void spiSend(uint8_t b) {
+    SPI.beginTransaction(spiConfig);
+    SPI.transfer(b);
+    SPI.endTransaction();
+  }
+
+  /**
+   * @brief  Write token and then write from 512 byte buffer to SPI (for SD card)
+   *
+   * @param  buf   Pointer with buffer start address
+   * @return Nothing
+   *
+   * @details Uses DMA
+   */
+  void spiSendBlock(uint8_t token, const uint8_t *buf) {
+    SPI.beginTransaction(spiConfig);
+    SPI.transfer(token);
+    SPI.transfer((uint8_t*)buf, 512);
+    SPI.endTransaction();
+  }
+
+  void spiBeginTransaction(uint32_t spiClock, uint8_t bitOrder, uint8_t dataMode) {
+    spiConfig = SPISettings(spiClock, (BitOrder)bitOrder, dataMode);
+    SPI.beginTransaction(spiConfig);
+  }
+#endif // !SOFTWARE_SPI
+
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/MarlinSPI.h

@@ -0,0 +1,31 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#pragma once
+
+#include <SPI.h>
+
+using MarlinSPI = SPIClass;

Marlin/src/HAL/SAMD21/QSPIFlash.cpp

@@ -0,0 +1,82 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(QSPI_EEPROM)
+
+#include "QSPIFlash.h"
+
+#define INVALID_ADDR    0xFFFFFFFF
+#define SECTOR_OF(a)    (a & ~(SFLASH_SECTOR_SIZE - 1))
+#define OFFSET_OF(a)    (a & (SFLASH_SECTOR_SIZE - 1))
+
+Adafruit_SPIFlashBase * QSPIFlash::_flashBase = nullptr;
+uint8_t QSPIFlash::_buf[SFLASH_SECTOR_SIZE];
+uint32_t QSPIFlash::_addr = INVALID_ADDR;
+
+void QSPIFlash::begin() {
+  if (_flashBase) return;
+
+  _flashBase = new Adafruit_SPIFlashBase(new Adafruit_FlashTransport_QSPI());
+  _flashBase->begin(nullptr);
+}
+
+size_t QSPIFlash::size() {
+  return _flashBase->size();
+}
+
+uint8_t QSPIFlash::readByte(const uint32_t address) {
+  if (SECTOR_OF(address) == _addr) return _buf[OFFSET_OF(address)];
+
+  return _flashBase->read8(address);
+}
+
+void QSPIFlash::writeByte(const uint32_t address, const uint8_t value) {
+  uint32_t const sector_addr = SECTOR_OF(address);
+
+  // Page changes, flush old and update new cache
+  if (sector_addr != _addr) {
+    flush();
+    _addr = sector_addr;
+
+    // read a whole page from flash
+    _flashBase->readBuffer(sector_addr, _buf, SFLASH_SECTOR_SIZE);
+  }
+
+  _buf[OFFSET_OF(address)] = value;
+}
+
+void QSPIFlash::flush() {
+  if (_addr == INVALID_ADDR) return;
+
+  _flashBase->eraseSector(_addr / SFLASH_SECTOR_SIZE);
+  _flashBase->writeBuffer(_addr, _buf, SFLASH_SECTOR_SIZE);
+
+  _addr = INVALID_ADDR;
+}
+
+#endif // QSPI_EEPROM

Marlin/src/HAL/SAMD21/QSPIFlash.h

@@ -0,0 +1,49 @@
+/**
+ * @file QSPIFlash.h
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach and Dean Miller for Adafruit Industries LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * Derived from Adafruit_SPIFlash class with no SdFat references
+ */
+#pragma once
+
+#include <Adafruit_SPIFlashBase.h>
+
+// This class extends Adafruit_SPIFlashBase by adding caching support.
+//
+// This class will use 4096 Bytes of RAM as a block cache.
+class QSPIFlash {
+  public:
+    static void begin();
+    static size_t size();
+    static uint8_t readByte(const uint32_t address);
+    static void writeByte(const uint32_t address, const uint8_t v);
+    static void flush();
+
+  private:
+    static Adafruit_SPIFlashBase * _flashBase;
+    static uint8_t _buf[SFLASH_SECTOR_SIZE];
+    static uint32_t _addr;
+};
+
+extern QSPIFlash qspi;

Marlin/src/HAL/SAMD21/SAMD21.h

@@ -0,0 +1,66 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+#define SYNC(sc)    while (sc) {  \
+                      asm("");    \
+                    }
+
+// Get SAMD port/pin from specified arduino pin
+#define GET_SAMD_PORT(P)    _GET_SAMD_PORT(PIN_TO_SAMD_PIN(P))
+#define GET_SAMD_PIN(P)     _GET_SAMD_PIN(PIN_TO_SAMD_PIN(P))
+
+// Get external interrupt line associated to specified arduino pin
+#define PIN_TO_EILINE(P)    _SAMDPORTPIN_TO_EILINE(GET_SAMD_PORT(P), GET_SAMD_PIN(P))
+
+// Get adc/ain associated to specified arduino pin
+#define PIN_TO_ADC(P)       (ANAPIN_TO_ADCAIN(P) >> 8)
+
+// Private defines
+#define PIN_TO_SAMD_PIN(P)    DIO##P##_PIN
+
+#define _GET_SAMD_PORT(P)     ((P) >> 5)
+#define _GET_SAMD_PIN(P)      ((P) & 0x1F)
+
+// Get external interrupt line
+#define _SAMDPORTPIN_TO_EILINE(P,B)   ((P == 0 && WITHIN(B, 0, 31) && B != 26 && B != 28 && B != 29) ? (B) & 0xF    \
+                                       : (P == 1 && (WITHIN(B, 0, 25) || WITHIN(B, 30, 31))) ? (B) & 0xF                      \
+                                       : (P == 1 && WITHIN(B, 26, 29)) ? 12 + (B) - 26                                        \
+                                       : (P == 2 && (WITHIN(B, 0, 6) || WITHIN(B, 10, 31)) && B != 29) ? (B) & 0xF            \
+                                       : (P == 2 && B == 7) ? 9                                                               \
+                                       : (P == 3 && WITHIN(B, 0, 1)) ? (B)                                                    \
+                                       : (P == 3 && WITHIN(B, 8, 12)) ? 3 + (B) - 8                                           \
+                                       : (P == 3 && WITHIN(B, 20, 21)) ? 10 + (B) - 20                                        \
+                                       : -1)
+
+
+
+#define A2_AIN 3
+#define A3_AIN 4
+#define A4_AIN 5
+#define PIN_TO_AIN(P)    A##P##_AIN
+#define AIN_TO_RESULT(P) ( (P - HAL_ADC_AIN_START == HAL_ADC_AIN_NUM_SENSORS-1) ? 0 :  (P - HAL_ADC_AIN_START + 1) )

Marlin/src/HAL/SAMD21/Servo.cpp

@@ -0,0 +1,220 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+/**
+ * This comes from Arduino library which at the moment is buggy and uncompilable
+ */
+
+#ifdef __SAMD21__
+
+#include "../../inc/MarlinConfig.h"
+
+#if HAS_SERVOS
+
+#include "../shared/servo.h"
+#include "../shared/servo_private.h"
+#include "SAMD21.h"
+
+#define __TC_GCLK_ID(t)         TC##t##_GCLK_ID
+#define _TC_GCLK_ID(t)          __TC_GCLK_ID(t)
+#define TC_GCLK_ID              _TC_GCLK_ID(SERVO_TC)
+
+#define _TC_PRESCALER(d)        TC_CTRLA_PRESCALER_DIV##d##_Val
+#define TC_PRESCALER(d)         _TC_PRESCALER(d)
+
+#define __SERVO_IRQn(t)         TC##t##_IRQn
+#define _SERVO_IRQn(t)          __SERVO_IRQn(t)
+#define SERVO_IRQn              _SERVO_IRQn(SERVO_TC)
+
+#define HAL_SERVO_TIMER_ISR()   TC_HANDLER(SERVO_TC)
+
+#define TIMER_TCCHANNEL(t)      ((t) & 1)
+#define TC_COUNTER_START_VAL    0xFFFF
+
+
+static volatile int8_t currentServoIndex[_Nbr_16timers];    // index for the servo being pulsed for each timer (or -1 if refresh interval)
+
+FORCE_INLINE static uint16_t getTimerCount() {
+  Tcc * const tc = timer_config[SERVO_TC].pTcc;
+
+  tc->CTRLBSET.reg = TCC_CTRLBCLR_CMD_READSYNC;
+  SYNC(tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+
+  return tc->COUNT.bit.COUNT;
+}
+
+// ----------------------------
+// Interrupt handler for the TC
+// ----------------------------
+HAL_SERVO_TIMER_ISR() {
+  Tcc * const tc = timer_config[SERVO_TC].pTcc;
+  const timer16_Sequence_t timer =
+    #ifndef _useTimer1
+      _timer2
+    #elif !defined(_useTimer2)
+      _timer1
+    #else
+      (tc->INTFLAG.reg & tc->INTENSET.reg & TC_INTFLAG_MC0) ? _timer1 : _timer2
+    #endif
+  ;
+  const uint8_t tcChannel = TIMER_TCCHANNEL(timer);
+
+  int8_t cho = currentServoIndex[timer];                // Handle the prior servo first
+  if (cho < 0) {                                        // Servo -1 indicates the refresh interval completed...
+    #if defined(_useTimer1) && defined(_useTimer2)
+      if (currentServoIndex[timer ^ 1] >= 0) {
+        // Wait for both channels
+        // Clear the interrupt
+        tc->INTFLAG.reg = (tcChannel == 0) ? TC_INTFLAG_MC0 : TC_INTFLAG_MC1;
+        return;
+      }
+    #endif
+    tc->COUNT.reg = TC_COUNTER_START_VAL;       // ...so reset the timer
+    SYNC(tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+  }
+  else if (SERVO_INDEX(timer, cho) < ServoCount)        // prior channel handled?
+    digitalWrite(SERVO(timer, cho).Pin.nbr, LOW);       // pulse the prior channel LOW
+
+  currentServoIndex[timer] = ++cho;                     // go to the next channel (or 0)
+  if (cho < SERVOS_PER_TIMER && SERVO_INDEX(timer, cho) < ServoCount) {
+    if (SERVO(timer, cho).Pin.isActive)                 // activated?
+      digitalWrite(SERVO(timer, cho).Pin.nbr, HIGH);    // yes: pulse HIGH
+
+    tc->CC[tcChannel].reg = getTimerCount() - (uint16_t)SERVO(timer, cho).ticks;
+  }
+  else {
+    // finished all channels so wait for the refresh period to expire before starting over
+    currentServoIndex[timer] = -1;                                          // reset the timer COUNT.reg on the next call
+    const uint16_t cval = getTimerCount() - 256 / (SERVO_TIMER_PRESCALER),  // allow 256 cycles to ensure the next CV not missed
+                   ival = (TC_COUNTER_START_VAL) - (uint16_t)usToTicks(REFRESH_INTERVAL); // at least REFRESH_INTERVAL has elapsed
+    tc->CC[tcChannel].reg = min(cval, ival);
+  }
+  if (tcChannel == 0) {
+    SYNC(tc->SYNCBUSY.bit.CC0);
+    tc->INTFLAG.reg = TC_INTFLAG_MC0; // Clear the interrupt
+  }
+  else {
+    SYNC(tc->SYNCBUSY.bit.CC1);
+    tc->INTFLAG.reg = TC_INTFLAG_MC1; // Clear the interrupt
+  }
+}
+
+void initISR(const timer16_Sequence_t timer) {
+  Tcc * const tc = timer_config[SERVO_TC].pTcc;
+  const uint8_t tcChannel = TIMER_TCCHANNEL(timer);
+
+  static bool initialized = false;  // Servo TC has been initialized
+  if (!initialized) {
+    NVIC_DisableIRQ(SERVO_IRQn);
+
+    // Disable the timer
+    tc->CTRLA.bit.ENABLE = false;
+    SYNC(tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+
+    // Select GCLK0 as timer/counter input clock source
+    GCLK->CLKCTRL.reg =(GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_ID(TCC0_GCLK_ID));
+    SYNC (GCLK->STATUS.bit.SYNCBUSY);
+
+    // Reset the timer
+    tc->CTRLA.bit.SWRST = true;
+    SYNC(tc->CTRLA.bit.SWRST);
+
+    // Set timer counter mode to 16 bits
+    tc->CTRLA.reg = TC_CTRLA_MODE_COUNT16;
+
+    // Set timer counter mode as normal PWM
+    tc->WAVE.bit.WAVEGEN = TCC_WAVE_WAVEGEN_NPWM_Val;
+
+    // Set the prescaler factor
+    tc->CTRLA.bit.PRESCALER = TC_PRESCALER(SERVO_TIMER_PRESCALER);
+
+    // Count down
+    tc->CTRLBSET.reg = TCC_CTRLBCLR_DIR;
+    SYNC(tc->SYNCBUSY.bit.CTRLB);
+
+    // Reset all servo indexes
+    memset((void *)currentServoIndex, 0xFF, sizeof(currentServoIndex));
+
+    // Configure interrupt request
+    NVIC_ClearPendingIRQ(SERVO_IRQn);
+    NVIC_SetPriority(SERVO_IRQn, 5);
+    NVIC_EnableIRQ(SERVO_IRQn);
+
+    initialized = true;
+  }
+
+  if (!tc->CTRLA.bit.ENABLE) {
+    // Reset the timer counter
+    tc->COUNT.reg = TC_COUNTER_START_VAL;
+    SYNC(tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+
+    // Enable the timer and start it
+    tc->CTRLA.bit.ENABLE = true;
+    SYNC(tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+  }
+  // First interrupt request after 1 ms
+  tc->CC[tcChannel].reg = getTimerCount() - (uint16_t)usToTicks(1000UL);
+
+  if (tcChannel == 0 ) {
+    SYNC(tc->SYNCBUSY.bit.CC0);
+
+    // Clear pending match interrupt
+    tc->INTFLAG.reg = TC_INTENSET_MC0;
+    // Enable the match channel interrupt request
+    tc->INTENSET.reg = TC_INTENSET_MC0;
+  }
+  else {
+    SYNC(tc->SYNCBUSY.bit.CC1);
+
+    // Clear pending match interrupt
+    tc->INTFLAG.reg = TC_INTENSET_MC1;
+    // Enable the match channel interrupt request
+    tc->INTENSET.reg = TC_INTENSET_MC1;
+  }
+}
+
+void finISR(const timer16_Sequence_t timer_index) {
+  Tcc * const tc = timer_config[SERVO_TC].pTcc;
+  const uint8_t tcChannel = TIMER_TCCHANNEL(timer_index);
+
+  // Disable the match channel interrupt request
+  tc->INTENCLR.reg = (tcChannel == 0) ? TC_INTENCLR_MC0 : TC_INTENCLR_MC1;
+
+  if (true
+    #if defined(_useTimer1) && defined(_useTimer2)
+      && (tc->INTENCLR.reg & (TC_INTENCLR_MC0|TC_INTENCLR_MC1)) == 0
+    #endif
+  ) {
+    // Disable the timer if not used
+    tc->CTRLA.bit.ENABLE = false;
+    SYNC(tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+  }
+}
+
+#endif // HAS_SERVOS
+
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/ServoTimers.h

@@ -0,0 +1,45 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+#define _useTimer1
+#define _useTimer2
+
+#define TRIM_DURATION           5   // compensation ticks to trim adjust for digitalWrite delays
+#define SERVO_TIMER_PRESCALER   64  // timer prescaler factor to 64 (avoid overflowing 16-bit clock counter, at 120MHz this is 1831 ticks per millisecond
+
+#define SERVO_TC                3
+
+typedef enum {
+  #ifdef _useTimer1
+    _timer1,
+  #endif
+  #ifdef _useTimer2
+    _timer2,
+  #endif
+  _Nbr_16timers
+} timer16_Sequence_t;

Marlin/src/HAL/SAMD21/eeprom_flash.cpp

@@ -0,0 +1,141 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#ifdef __SAMD21__
+
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(FLASH_EEPROM_EMULATION)
+
+#define TOTAL_FLASH_SIZE (MARLIN_EEPROM_SIZE+255)/256*256
+
+/* reserve flash memory */
+static const uint8_t flashdata[TOTAL_FLASH_SIZE]  __attribute__((__aligned__(256))) { }; \
+
+#include "../shared/eeprom_api.h"
+
+size_t PersistentStore::capacity() {
+  return MARLIN_EEPROM_SIZE;
+ /* const uint8_t psz = NVMCTRL->SEESTAT.bit.PSZ,
+                sblk = NVMCTRL->SEESTAT.bit.SBLK;
+
+  return   (!psz && !sblk)         ? 0
+         : (psz <= 2)              ? (0x200 << psz)
+         : (sblk == 1 || psz == 3) ?  4096
+         : (sblk == 2 || psz == 4) ?  8192
+         : (sblk <= 4 || psz == 5) ? 16384
+         : (sblk >= 9 && psz == 7) ? 65536
+                                   : 32768;*/
+}
+
+uint32_t PAGE_SIZE;
+uint32_t ROW_SIZE;
+bool hasWritten = false;
+uint8_t * buffer;
+
+void _erase(const volatile void *flash_ptr) {
+  NVMCTRL->ADDR.reg = ((uint32_t)flash_ptr) / 2;
+  NVMCTRL->CTRLA.reg = NVMCTRL_CTRLA_CMDEX_KEY | NVMCTRL_CTRLA_CMD_ER;
+  while (!NVMCTRL->INTFLAG.bit.READY) { }
+
+}
+
+void erase(const volatile void *flash_ptr, uint32_t size) {
+  const uint8_t *ptr = (const uint8_t *)flash_ptr;
+  while (size > ROW_SIZE) {
+    _erase(ptr);
+    ptr += ROW_SIZE;
+    size -= ROW_SIZE;
+  }
+  _erase(ptr);
+}
+
+bool PersistentStore::access_start() {
+  /* clear page buffer*/
+  NVMCTRL->CTRLA.reg = NVMCTRL_CTRLA_CMDEX_KEY | NVMCTRL_CTRLA_CMD_PBC;
+  while (NVMCTRL->INTFLAG.bit.READY == 0) { }
+
+  PAGE_SIZE =  pow(2,3 + NVMCTRL->PARAM.bit.PSZ);
+  ROW_SIZE= PAGE_SIZE * 4;
+  /*NVMCTRL->SEECFG.reg = NVMCTRL_SEECFG_WMODE_BUFFERED;  // Buffered mode and segment reallocation active
+  if (NVMCTRL->SEESTAT.bit.RLOCK)
+    NVMCTRL_CMD(NVMCTRL_CTRLB_CMD_USEE);  */  // Unlock E2P data write access
+  //   erase(&flashdata[0], TOTAL_FLASH_SIZE);
+  return true;
+}
+
+bool PersistentStore::access_finish() {
+  if (hasWritten) {
+    erase(&flashdata[0], TOTAL_FLASH_SIZE);
+
+    NVMCTRL->CTRLA.reg = NVMCTRL_CTRLA_CMDEX_KEY | NVMCTRL_CTRLA_CMD_PBC;
+    while (NVMCTRL->INTFLAG.bit.READY == 0) { }
+
+     NVMCTRL->CTRLB.bit.MANW = 0;
+
+    volatile uint32_t *dst_addr =  (volatile uint32_t *) &flashdata;
+
+    uint32_t *pointer = (uint32_t *) buffer;
+    for (uint32_t i = 0; i < TOTAL_FLASH_SIZE; i+=4) {
+
+      *dst_addr = (uint32_t) *pointer;
+      pointer++;
+      dst_addr ++;
+    }
+
+    // Execute "WP" Write Page
+    NVMCTRL->CTRLA.reg = NVMCTRL_CTRLA_CMDEX_KEY | NVMCTRL_CTRLA_CMD_WP;
+    while (NVMCTRL->INTFLAG.bit.READY == 0) { }
+
+    free(buffer);
+    hasWritten = false;
+  }
+  return true;
+}
+
+bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  if (!hasWritten) {
+    // init temp buffer
+    buffer = (uint8_t *) malloc(MARLIN_EEPROM_SIZE);
+    hasWritten=true;
+  }
+
+  memcpy(buffer+pos,value,size);
+  pos += size;
+  return false;
+}
+
+bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
+  volatile uint8_t *dst_addr =  (volatile uint8_t *) &flashdata;
+  dst_addr += pos;
+
+  memcpy(value,(const void *) dst_addr,size);
+  pos += size;
+  return false;
+}
+
+#endif // FLASH_EEPROM_EMULATION
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/eeprom_qspi.cpp

@@ -0,0 +1,79 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#ifdef __SAMD21__
+
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(QSPI_EEPROM)
+
+#error "QSPI_EEPROM emulation Not implemented on SAMD21"
+
+#include "../shared/eeprom_api.h"
+
+#include "QSPIFlash.h"
+
+static bool initialized;
+
+size_t PersistentStore::capacity() { return qspi.size(); }
+
+bool PersistentStore::access_start() {
+  if (!initialized) {
+    qspi.begin();
+    initialized = true;
+  }
+  return true;
+}
+
+bool PersistentStore::access_finish() {
+  qspi.flush();
+  return true;
+}
+
+bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  while (size--) {
+    const uint8_t v = *value;
+    qspi.writeByte(pos, v);
+    crc16(crc, &v, 1);
+    pos++;
+    value++;
+  }
+  return false;
+}
+
+bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
+  while (size--) {
+    uint8_t c = qspi.readByte(pos);
+    if (writing) *value = c;
+    crc16(crc, &c, 1);
+    pos++;
+    value++;
+  }
+  return false;
+}
+
+#endif // QSPI_EEPROM
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/eeprom_wired.cpp

@@ -0,0 +1,82 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#ifdef __SAMD21__
+
+#include "../../inc/MarlinConfig.h"
+
+#if USE_WIRED_EEPROM
+
+#error "USE_WIRED_EEPROM emulation Not implemented on SAMD21"
+/**
+ * PersistentStore for Arduino-style EEPROM interface
+ * with simple implementations supplied by Marlin.
+ */
+
+#include "../shared/eeprom_if.h"
+#include "../shared/eeprom_api.h"
+
+#ifndef MARLIN_EEPROM_SIZE
+  #error "MARLIN_EEPROM_SIZE is required for I2C / SPI EEPROM."
+#endif
+size_t PersistentStore::capacity()    { return MARLIN_EEPROM_SIZE; }
+
+bool PersistentStore::access_start()  { eeprom_init(); return true; }
+bool PersistentStore::access_finish() { return true; }
+
+bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
+  while (size--) {
+    const uint8_t v = *value;
+    uint8_t * const p = (uint8_t * const)pos;
+    if (v != eeprom_read_byte(p)) { // EEPROM has only ~100,000 write cycles, so only write bytes that have changed!
+      eeprom_write_byte(p, v);
+      if (++written & 0x7F) delay(2); else safe_delay(2); // Avoid triggering watchdog during long EEPROM writes
+      if (eeprom_read_byte(p) != v) {
+        SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
+        return true;
+      }
+    }
+    crc16(crc, &v, 1);
+    pos++;
+    value++;
+  }
+  return false;
+}
+
+bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
+  while (size--) {
+    uint8_t c = eeprom_read_byte((uint8_t*)pos);
+    if (writing) *value = c;
+    crc16(crc, &c, 1);
+    pos++;
+    value++;
+  }
+  return false;
+}
+
+#endif // USE_WIRED_EEPROM
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/endstop_interrupts.h

@@ -0,0 +1,253 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+/**
+ * Endstop interrupts for ATMEL SAMD21 based targets.
+ *
+ * On SAMD21, all pins support external interrupt capability.
+ * Any pin can be used for external interrupts, but there are some restrictions.
+ * At most 16 different external interrupts can be used at one time.
+ * Further, you can’t just pick any 16 pins to use. This is because every pin on the SAMD21
+ * connects to what is called an EXTINT line, and only one pin per EXTINT line can be used for external
+ * interrupts at a time
+ */
+
+/**
+ * Endstop Interrupts
+ *
+ * Without endstop interrupts the endstop pins must be polled continually in
+ * the temperature-ISR via endstops.update(), most of the time finding no change.
+ * With this feature endstops.update() is called only when we know that at
+ * least one endstop has changed state, saving valuable CPU cycles.
+ *
+ * This feature only works when all used endstop pins can generate an 'external interrupt'.
+ *
+ * Test whether pins issue interrupts on your board by flashing 'pin_interrupt_test.ino'.
+ * (Located in Marlin/buildroot/share/pin_interrupt_test/pin_interrupt_test.ino)
+ */
+
+#include "../../module/endstops.h"
+
+#define MATCH_EILINE(P1,P2) (P1 != P2 && PIN_TO_EILINE(P1) == PIN_TO_EILINE(P2))
+#define MATCH_X_MAX_EILINE(P)   TERN0(HAS_X_MAX,  DEFER4(MATCH_EILINE)(P, X_MAX_PIN))
+#define MATCH_X_MIN_EILINE(P)   TERN0(HAS_X_MIN,  DEFER4(MATCH_EILINE)(P, X_MIN_PIN))
+#define MATCH_Y_MAX_EILINE(P)   TERN0(HAS_Y_MAX,  DEFER4(MATCH_EILINE)(P, Y_MAX_PIN))
+#define MATCH_Y_MIN_EILINE(P)   TERN0(HAS_Y_MIN,  DEFER4(MATCH_EILINE)(P, Y_MIN_PIN))
+#define MATCH_Z_MAX_EILINE(P)   TERN0(HAS_Z_MAX,  DEFER4(MATCH_EILINE)(P, Z_MAX_PIN))
+#define MATCH_Z_MIN_EILINE(P)   TERN0(HAS_Z_MIN,  DEFER4(MATCH_EILINE)(P, Z_MIN_PIN))
+#define MATCH_I_MAX_EILINE(P)   TERN0(HAS_I_MAX,  DEFER4(MATCH_EILINE)(P, I_MAX_PIN))
+#define MATCH_I_MIN_EILINE(P)   TERN0(HAS_I_MIN,  DEFER4(MATCH_EILINE)(P, I_MIN_PIN))
+#define MATCH_J_MAX_EILINE(P)   TERN0(HAS_J_MAX,  DEFER4(MATCH_EILINE)(P, J_MAX_PIN))
+#define MATCH_J_MIN_EILINE(P)   TERN0(HAS_J_MIN,  DEFER4(MATCH_EILINE)(P, J_MIN_PIN))
+#define MATCH_K_MAX_EILINE(P)   TERN0(HAS_K_MAX,  DEFER4(MATCH_EILINE)(P, K_MAX_PIN))
+#define MATCH_K_MIN_EILINE(P)   TERN0(HAS_K_MIN,  DEFER4(MATCH_EILINE)(P, K_MIN_PIN))
+#define MATCH_U_MAX_EILINE(P)   TERN0(HAS_U_MAX,  DEFER4(MATCH_EILINE)(P, U_MAX_PIN))
+#define MATCH_U_MIN_EILINE(P)   TERN0(HAS_U_MIN,  DEFER4(MATCH_EILINE)(P, U_MIN_PIN))
+#define MATCH_V_MAX_EILINE(P)   TERN0(HAS_V_MAX,  DEFER4(MATCH_EILINE)(P, V_MAX_PIN))
+#define MATCH_V_MIN_EILINE(P)   TERN0(HAS_V_MIN,  DEFER4(MATCH_EILINE)(P, V_MIN_PIN))
+#define MATCH_W_MAX_EILINE(P)   TERN0(HAS_W_MAX,  DEFER4(MATCH_EILINE)(P, W_MAX_PIN))
+#define MATCH_W_MIN_EILINE(P)   TERN0(HAS_W_MIN,  DEFER4(MATCH_EILINE)(P, W_MIN_PIN))
+#define MATCH_Z2_MAX_EILINE(P)  TERN0(HAS_Z2_MAX, DEFER4(MATCH_EILINE)(P, Z2_MAX_PIN))
+#define MATCH_Z2_MIN_EILINE(P)  TERN0(HAS_Z2_MIN, DEFER4(MATCH_EILINE)(P, Z2_MIN_PIN))
+#define MATCH_Z3_MAX_EILINE(P)  TERN0(HAS_Z3_MAX, DEFER4(MATCH_EILINE)(P, Z3_MAX_PIN))
+#define MATCH_Z3_MIN_EILINE(P)  TERN0(HAS_Z3_MIN, DEFER4(MATCH_EILINE)(P, Z3_MIN_PIN))
+#define MATCH_Z4_MAX_EILINE(P)  TERN0(HAS_Z4_MAX, DEFER4(MATCH_EILINE)(P, Z4_MAX_PIN))
+#define MATCH_Z4_MIN_EILINE(P)  TERN0(HAS_Z4_MIN, DEFER4(MATCH_EILINE)(P, Z4_MIN_PIN))
+#define MATCH_Z_MIN_PROBE_EILINE(P) TERN0(HAS_Z_MIN_PROBE_PIN, DEFER4(MATCH_EILINE)(P, Z_MIN_PROBE_PIN))
+
+#define AVAILABLE_EILINE(P) ( PIN_TO_EILINE(P) != -1    \
+  && !MATCH_X_MAX_EILINE(P) && !MATCH_X_MIN_EILINE(P)   \
+  && !MATCH_Y_MAX_EILINE(P) && !MATCH_Y_MIN_EILINE(P)   \
+  && !MATCH_Z_MAX_EILINE(P) && !MATCH_Z_MIN_EILINE(P)   \
+  && !MATCH_I_MAX_EILINE(P) && !MATCH_I_MIN_EILINE(P)   \
+  && !MATCH_J_MAX_EILINE(P) && !MATCH_J_MIN_EILINE(P)   \
+  && !MATCH_K_MAX_EILINE(P) && !MATCH_K_MIN_EILINE(P)   \
+  && !MATCH_U_MAX_EILINE(P) && !MATCH_U_MIN_EILINE(P)   \
+  && !MATCH_V_MAX_EILINE(P) && !MATCH_V_MIN_EILINE(P)   \
+  && !MATCH_W_MAX_EILINE(P) && !MATCH_W_MIN_EILINE(P)   \
+  && !MATCH_Z2_MAX_EILINE(P) && !MATCH_Z2_MIN_EILINE(P) \
+  && !MATCH_Z3_MAX_EILINE(P) && !MATCH_Z3_MIN_EILINE(P) \
+  && !MATCH_Z4_MAX_EILINE(P) && !MATCH_Z4_MIN_EILINE(P) \
+  && !MATCH_Z_MIN_PROBE_EILINE(P) )
+
+// One ISR for all EXT-Interrupts
+void endstop_ISR() { endstops.update(); }
+
+void setup_endstop_interrupts() {
+  #define _ATTACH(P) attachInterrupt(P, endstop_ISR, CHANGE)
+  #if HAS_X_MAX
+    #if !AVAILABLE_EILINE(X_MAX_PIN)
+      #error "X_MAX_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(X_MAX_PIN);
+  #endif
+  #if HAS_X_MIN
+    #if !AVAILABLE_EILINE(X_MIN_PIN)
+      #error "X_MIN_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(X_MIN_PIN);
+  #endif
+  #if HAS_Y_MAX
+    #if !AVAILABLE_EILINE(Y_MAX_PIN)
+      #error "Y_MAX_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Y_MAX_PIN);
+  #endif
+  #if HAS_Y_MIN
+    #if !AVAILABLE_EILINE(Y_MIN_PIN)
+      #error "Y_MIN_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Y_MIN_PIN);
+  #endif
+  #if HAS_Z_MAX
+    #if !AVAILABLE_EILINE(Z_MAX_PIN)
+      #error "Z_MAX_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z_MAX_PIN);
+  #endif
+  #if HAS_Z_MIN
+    #if !AVAILABLE_EILINE(Z_MIN_PIN)
+      #error "Z_MIN_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z_MIN_PIN);
+  #endif
+  #if HAS_Z2_MAX
+    #if !AVAILABLE_EILINE(Z2_MAX_PIN)
+      #error "Z2_MAX_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z2_MAX_PIN);
+  #endif
+  #if HAS_Z2_MIN
+    #if !AVAILABLE_EILINE(Z2_MIN_PIN)
+      #error "Z2_MIN_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z2_MIN_PIN);
+  #endif
+  #if HAS_Z3_MAX
+    #if !AVAILABLE_EILINE(Z3_MAX_PIN)
+      #error "Z3_MAX_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z3_MAX_PIN);
+  #endif
+  #if HAS_Z3_MIN
+    #if !AVAILABLE_EILINE(Z3_MIN_PIN)
+      #error "Z3_MIN_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z3_MIN_PIN);
+  #endif
+  #if HAS_Z4_MAX
+    #if !AVAILABLE_EILINE(Z4_MAX_PIN)
+      #error "Z4_MAX_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z4_MAX_PIN);
+  #endif
+  #if HAS_Z4_MIN
+    #if !AVAILABLE_EILINE(Z4_MIN_PIN)
+      #error "Z4_MIN_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z4_MIN_PIN);
+  #endif
+  #if HAS_Z_MIN_PROBE_PIN
+    #if !AVAILABLE_EILINE(Z_MIN_PROBE_PIN)
+      #error "Z_MIN_PROBE_PIN has no EXTINT line available."
+    #endif
+    _ATTACH(Z_MIN_PROBE_PIN);
+  #endif
+  #if HAS_I_MAX
+    #if !AVAILABLE_EILINE(I_MAX_PIN)
+      #error "I_MAX_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(I_MAX_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_I_MIN
+    #if !AVAILABLE_EILINE(I_MIN_PIN)
+      #error "I_MIN_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(I_MIN_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_J_MAX
+    #if !AVAILABLE_EILINE(J_MAX_PIN)
+      #error "J_MAX_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(J_MAX_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_J_MIN
+    #if !AVAILABLE_EILINE(J_MIN_PIN)
+      #error "J_MIN_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(J_MIN_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_K_MAX
+    #if !AVAILABLE_EILINE(K_MAX_PIN)
+      #error "K_MAX_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(K_MAX_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_K_MIN
+    #if !AVAILABLE_EILINE(K_MIN_PIN)
+      #error "K_MIN_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(K_MIN_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_U_MAX
+    #if !AVAILABLE_EILINE(U_MAX_PIN)
+      #error "U_MAX_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(U_MAX_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_U_MIN
+    #if !AVAILABLE_EILINE(U_MIN_PIN)
+      #error "U_MIN_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(U_MIN_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_V_MAX
+    #if !AVAILABLE_EILINE(V_MAX_PIN)
+      #error "V_MAX_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(V_MAX_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_V_MIN
+    #if !AVAILABLE_EILINE(V_MIN_PIN)
+      #error "V_MIN_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(V_MIN_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_W_MAX
+    #if !AVAILABLE_EILINE(W_MAX_PIN)
+      #error "W_MAX_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(W_MAX_PIN, endstop_ISR, CHANGE);
+  #endif
+  #if HAS_W_MIN
+    #if !AVAILABLE_EILINE(W_MIN_PIN)
+      #error "W_MIN_PIN has no EXTINT line available."
+    #endif
+    attachInterrupt(W_MIN_PIN, endstop_ISR, CHANGE);
+  #endif
+}

Marlin/src/HAL/SAMD21/fastio.h

@@ -0,0 +1,215 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+/**
+ * Fast IO functions for SAMD21
+ */
+
+#include "SAMD21.h"
+
+/**
+ * Utility functions
+ */
+
+#ifndef MASK
+  #define MASK(PIN) _BV(PIN)
+#endif
+
+/**
+ * Magic I/O routines
+ *
+ * Now you can simply SET_OUTPUT(IO); WRITE(IO, HIGH); WRITE(IO, LOW);
+ */
+
+// Read a pin
+#define READ(IO)        ((PORT->Group[(EPortType)GET_SAMD_PORT(IO)].IN.reg & MASK(GET_SAMD_PIN(IO))) != 0)
+
+// Write to a pin
+#define WRITE(IO,V)     do{                                                     \
+                          const EPortType port = (EPortType)GET_SAMD_PORT(IO);  \
+                          const uint32_t mask = MASK(GET_SAMD_PIN(IO));         \
+                                                                                \
+                          if (V) PORT->Group[port].OUTSET.reg = mask;           \
+                          else PORT->Group[port].OUTCLR.reg = mask;             \
+                        }while(0)
+
+// Toggle a pin
+#define TOGGLE(IO)      PORT->Group[(EPortType)GET_SAMD_PORT(IO)].OUTTGL.reg = MASK(GET_SAMD_PIN(IO));
+
+// Set pin as input
+#define SET_INPUT(IO)           do{                                                                 \
+                                  const EPortType port = (EPortType)GET_SAMD_PORT(IO);              \
+                                  const uint32_t pin = GET_SAMD_PIN(IO);                            \
+                                                                                                    \
+                                  PORT->Group[port].PINCFG[pin].reg = (uint8_t)(PORT_PINCFG_INEN);  \
+                                  PORT->Group[port].DIRCLR.reg = MASK(pin);                         \
+                                }while(0)
+// Set pin as input with pullup
+#define SET_INPUT_PULLUP(IO)    do{                                                                                       \
+                                  const EPortType port = (EPortType)GET_SAMD_PORT(IO);                                    \
+                                  const uint32_t pin = GET_SAMD_PIN(IO);                                                  \
+                                  const uint32_t mask = MASK(pin);                                                        \
+                                                                                                                          \
+                                  PORT->Group[port].PINCFG[pin].reg = (uint8_t)(PORT_PINCFG_INEN | PORT_PINCFG_PULLEN);   \
+                                  PORT->Group[port].DIRCLR.reg = mask;                                                    \
+                                  PORT->Group[port].OUTSET.reg = mask;                                                    \
+                                }while(0)
+// Set pin as input with pulldown
+#define SET_INPUT_PULLDOWN(IO)  do{                                                                                       \
+                                  const EPortType port = (EPortType)GET_SAMD_PORT(IO);                                    \
+                                  const uint32_t pin = GET_SAMD_PIN(IO);                                                  \
+                                  const uint32_t mask = MASK(pin);                                                        \
+                                                                                                                          \
+                                  PORT->Group[port].PINCFG[pin].reg = (uint8_t)(PORT_PINCFG_INEN | PORT_PINCFG_PULLEN);   \
+                                  PORT->Group[port].DIRCLR.reg = mask;                                                    \
+                                  PORT->Group[port].OUTCLR.reg = mask;                                                    \
+                                }while(0)
+// Set pin as output (push pull)
+#define SET_OUTPUT(IO)          do{                                                                 \
+                                  const EPortType port = (EPortType)GET_SAMD_PORT(IO);              \
+                                  const uint32_t pin = GET_SAMD_PIN(IO);                            \
+                                                                                                    \
+                                  PORT->Group[port].DIRSET.reg = MASK(pin);                         \
+                                  PORT->Group[port].PINCFG[pin].reg = 0;                            \
+                                }while(0)
+// Set pin as output (open drain)
+#define SET_OUTPUT_OD(IO)       do{                                                                   \
+                                  const EPortType port = (EPortType)GET_SAMD_PORT(IO);                \
+                                  const uint32_t pin = GET_SAMD_PIN(IO);                              \
+                                                                                                      \
+                                  PORT->Group[port].PINCFG[pin].reg = (uint8_t)(PORT_PINCFG_PULLEN);  \
+                                  PORT->Group[port].DIRCLR.reg = MASK(pin);                           \
+                                }while(0)
+// Set pin as PWM (push pull)
+#define SET_PWM                 SET_OUTPUT
+// Set pin as PWM (open drain)
+#define SET_PWM_OD              SET_OUTPUT_OD
+
+// check if pin is an output
+#define IS_OUTPUT(IO)            ((PORT->Group[(EPortType)GET_SAMD_PORT(IO)].DIR.reg & MASK(GET_SAMD_PIN(IO))) \
+                                 || (PORT->Group[(EPortType)GET_SAMD_PORT(IO)].PINCFG[GET_SAMD_PIN(IO)].reg & (PORT_PINCFG_INEN | PORT_PINCFG_PULLEN)) == PORT_PINCFG_PULLEN)
+// check if pin is an input
+#define IS_INPUT(IO)            !IS_OUTPUT(IO)
+
+// Shorthand
+#define OUT_WRITE(IO,V)         do{ SET_OUTPUT(IO); WRITE(IO,V); }while(0)
+#define OUT_WRITE_OD(IO,V)      do{ SET_OUTPUT_OD(IO); WRITE(IO,V); }while(0)
+
+// digitalRead/Write wrappers
+#define extDigitalRead(IO)      digitalRead(IO)
+#define extDigitalWrite(IO,V)   digitalWrite(IO,V)
+
+/**
+ * Ports and functions
+ * Added as necessary or if I feel like it- not a comprehensive list!
+ */
+
+/*
+ * Some of these share the same source and so can't be used in the same time
+ */
+#define PWM_PIN(P)        (WITHIN(P, 2, 13) || WITHIN(P, 22, 23) || WITHIN(P, 44, 45) || P == 48)
+
+// Return fulfilled ADCx->INPUTCTRL.reg
+#define PIN_TO_INPUTCTRL(P)     (  (P == 0) ? ADC_INPUTCTRL_MUXPOS_PIN0   \
+                                 : ((P) == 1) ? ADC_INPUTCTRL_MUXPOS_PIN1   \
+                                 : ((P) == 2) ? ADC_INPUTCTRL_MUXPOS_PIN3   \
+                                 : ((P) == 3) ? ADC_INPUTCTRL_MUXPOS_PIN4   \
+                                 : ((P) == 4) ? ADC_INPUTCTRL_MUXPOS_PIN5   \
+                                 : ((P) == 5) ? ADC_INPUTCTRL_MUXPOS_PIN5   \
+                                 : ((P) == 6) ? ADC_INPUTCTRL_MUXPOS_PIN6   \
+                                 : ((P) == 7) ? ADC_INPUTCTRL_MUXPOS_PIN7   \
+                                 : ((P) == 8) ? ADC_INPUTCTRL_MUXPOS_PIN8   \
+                                 : ((P) == 9) ? ADC_INPUTCTRL_MUXPOS_PIN9   \
+                                 : ((P) == 10) ? ADC_INPUTCTRL_MUXPOS_PIN10 \
+                                 : ((P) == 11) ? ADC_INPUTCTRL_MUXPOS_PIN11 \
+                                 : ((P) == 12) ? ADC_INPUTCTRL_MUXPOS_PIN12 \
+                                 : ((P) == 13) ? ADC_INPUTCTRL_MUXPOS_PIN13 \
+                                 : ((P) == 14) ? ADC_INPUTCTRL_MUXPOS_PIN14 \
+                                 : ADC_INPUTCTRL_MUXPOS_PIN15)
+
+#define digitalPinToAnalogInput(P) (WITHIN(P, 67, 74) ? (P) - 67 : WITHIN(P, 54, 61) ? 8 + (P) - 54 : WITHIN(P, 12, 13) ? 16 + (P) - 12 : P == 9 ? 18 : -1)
+
+/**
+ * pins
+ */
+
+// PORTA
+#define DIO28_PIN   PIN_PA02    // A0
+#define DIO56_PIN   PIN_PA03    // A13
+#define DIO31_PIN   PIN_PA04    // A13
+#define DIO32_PIN   PIN_PA05    // A1
+#define DIO8_PIN    PIN_PA06    // A14
+#define DIO9_PIN    PIN_PA07    // A15
+#define DIO4_PIN    PIN_PA08    // A15
+#define DIO3_PIN    PIN_PA09    // A15
+#define DIO1_PIN    PIN_PA10
+#define DIO0_PIN    PIN_PA11
+#define DIO18_PIN   PIN_PA12
+#define DIO52_PIN   PIN_PA13
+#define DIO2_PIN    PIN_PA14
+#define DIO5_PIN    PIN_PA15
+#define DIO11_PIN   PIN_PA16
+#define DIO13_PIN   PIN_PA17
+#define DIO10_PIN   PIN_PA18
+#define DIO12_PIN   PIN_PA19
+#define DIO6_PIN    PIN_PA20
+#define DIO07_PIN   PIN_PA21
+#define DIO34_PIN   PIN_PA22
+#define DIO35_PIN   PIN_PA23
+#define DIO42_PIN   PIN_PA24
+#define DIO43_PIN   PIN_PA25
+
+#define DIO40_PIN   PIN_PA27
+
+#define DIO26_PIN   PIN_PB00
+#define DIO27_PIN   PIN_PB01    // A0
+#define DIO33_PIN   PIN_PB02
+#define DIO39_PIN   PIN_PB03
+#define DIO14_PIN   PIN_PB04
+#define DIO15_PIN   PIN_PB05
+#define DIO16_PIN   PIN_PB06
+#define DIO17_PIN   PIN_PB07
+#define DIO29_PIN   PIN_PB08
+#define DIO30_PIN   PIN_PB09
+#define DIO37_PIN   PIN_PB10
+#define DIO38_PIN   PIN_PB11
+#define DIO36_PIN   PIN_PB12
+#define DIO19_PIN   PIN_PB13
+#define DIO20_PIN   PIN_PB14
+#define DIO21_PIN   PIN_PB15
+#define DIO22_PIN   PIN_PB16
+#define DIO23_PIN   PIN_PB17
+
+#define DIO44_PIN   PIN_PB22
+#define DIO45_PIN   PIN_PB23
+#define DIO24_PIN   PIN_PB30
+#define DIO25_PIN   PIN_PB31
+
+#define DIO53_PIN   PIN_PA21
+#define DIO54_PIN   PIN_PA06
+#define DIO55_PIN   PIN_PA07

Marlin/src/HAL/SAMD21/inc/Conditionals_LCD.h

@@ -0,0 +1,23 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#pragma once

Marlin/src/HAL/SAMD21/inc/Conditionals_adv.h

@@ -0,0 +1,27 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#pragma once

Marlin/src/HAL/SAMD21/inc/Conditionals_post.h

@@ -0,0 +1,33 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#pragma once
+
+#if USE_FALLBACK_EEPROM
+  #define FLASH_EEPROM_EMULATION
+#elif EITHER(I2C_EEPROM, SPI_EEPROM)
+  #define USE_SHARED_EEPROM 1
+#endif

Marlin/src/HAL/SAMD21/inc/SanityCheck.h

@@ -0,0 +1,54 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+/**
+ * Test SAMD21 specific configuration values for errors at compile-time.
+ */
+
+#if HAS_SPI_TFT || HAS_FSMC_TFT
+  #error "Sorry! TFT displays are not available for HAL/SAMD21."
+#endif
+
+#if SERVO_TC == MF_TIMER_RTC
+  #error "Servos can't use RTC timer"
+#endif
+
+#if ENABLED(EMERGENCY_PARSER)
+  #error "EMERGENCY_PARSER is not yet implemented for SAMD21. Disable EMERGENCY_PARSER to continue."
+#endif
+
+#if ENABLED(SDIO_SUPPORT)
+  #error "SDIO_SUPPORT is not supported on SAMD21."
+#endif
+
+#if ENABLED(FAST_PWM_FAN)
+  #error "Features requiring Hardware PWM (FAST_PWM_FAN) are not yet supported for HAL/SAMD21."
+#endif
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  #error "POSTMORTEM_DEBUGGING is not yet supported on SAMD21."
+#endif

Marlin/src/HAL/SAMD21/pinsDebug.h

@@ -0,0 +1,160 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+#define NUMBER_PINS_TOTAL PINS_COUNT
+
+#define digitalRead_mod(p) extDigitalRead(p)
+#define PRINT_PORT(p) do{ SERIAL_ECHOPGM("  Port: "); sprintf_P(buffer, PSTR("%c%02ld"), 'A' + g_APinDescription[p].ulPort, g_APinDescription[p].ulPin); SERIAL_ECHO(buffer); }while (0)
+#define PRINT_ARRAY_NAME(x) do{ sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); }while(0)
+#define PRINT_PIN(p) do{ sprintf_P(buffer, PSTR("%3d "), p); SERIAL_ECHO(buffer); }while(0)
+#define PRINT_PIN_ANALOG(p) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), DIGITAL_PIN_TO_ANALOG_PIN(pin)); SERIAL_ECHO(buffer); }while(0)
+#define GET_ARRAY_PIN(p) pin_array[p].pin
+#define GET_ARRAY_IS_DIGITAL(p) pin_array[p].is_digital
+#define VALID_PIN(pin) (pin >= 0 && pin < (int8_t)NUMBER_PINS_TOTAL)
+#define DIGITAL_PIN_TO_ANALOG_PIN(p) digitalPinToAnalogInput(p)
+#define IS_ANALOG(P) (DIGITAL_PIN_TO_ANALOG_PIN(P)!=-1)
+#define pwm_status(pin) digitalPinHasPWM(pin)
+#define MULTI_NAME_PAD 27 // space needed to be pretty if not first name assigned to a pin
+
+// pins that will cause hang/reset/disconnect in M43 Toggle and Watch utilities
+// uses pin index
+#define M43_NEVER_TOUCH(Q) ((Q) >= 75)
+
+bool GET_PINMODE(int8_t pin) {  // 1: output, 0: input
+  const EPortType samdport = g_APinDescription[pin].ulPort;
+  const uint32_t samdpin = g_APinDescription[pin].ulPin;
+  return PORT->Group[samdport].DIR.reg & MASK(samdpin) || (PORT->Group[samdport].PINCFG[samdpin].reg & (PORT_PINCFG_INEN | PORT_PINCFG_PULLEN)) == PORT_PINCFG_PULLEN;
+}
+
+void pwm_details(int32_t pin) {
+  if (pwm_status(pin)) {
+    //uint32_t chan = g_APinDescription[pin].ulPWMChannel TODO when fast pwm is operative;
+    //SERIAL_ECHOPGM("PWM = ", duty);
+  }
+}
+
+/**
+ * SAMD21 Board pin|  PORT  | Label
+ * ----------------+--------+-------
+ *   0             |  PB25  | "RX0"
+ *   1             |  PB24  | "TX0"
+ *   2             |  PC18  |
+ *   3             |  PC19  |
+ *   4             |  PC20  |
+ *   5             |  PC21  |
+ *   6             |  PD20  |
+ *   7             |  PD21  |
+ *   8             |  PB18  |
+ *   9             |  PB2   |
+ *  10             |  PB22  |
+ *  11             |  PB23  |
+ *  12             |  PB0   | "A16"
+ *  13             |  PB1   | LED AMBER "L" / "A17"
+ *  14             |  PB16  | "TX3"
+ *  15             |  PB17  | "RX3"
+ *  16             |  PC22  | "TX2"
+ *  17             |  PC23  | "RX2"
+ *  18             |  PB12  | "TX1" / "A18"
+ *  19             |  PB13  | "RX1"
+ *  20             |  PB20  | "SDA"
+ *  21             |  PB21  | "SCL"
+ *  22             |  PD12  |
+ *  23             |  PA15  |
+ *  24             |  PC17  |
+ *  25             |  PC16  |
+ *  26             |  PA12  |
+ *  27             |  PA13  |
+ *  28             |  PA14  |
+ *  29             |  PB19  |
+ *  30             |  PA23  |
+ *  31             |  PA22  |
+ *  32             |  PA21  |
+ *  33             |  PA20  |
+ *  34             |  PA19  |
+ *  35             |  PA18  |
+ *  36             |  PA17  |
+ *  37             |  PA16  |
+ *  38             |  PB15  |
+ *  39             |  PB14  |
+ *  40             |  PC13  |
+ *  41             |  PC12  |
+ *  42             |  PC15  |
+ *  43             |  PC14  |
+ *  44             |  PC11  |
+ *  45             |  PC10  |
+ *  46             |  PC6   |
+ *  47             |  PC7   |
+ *  48             |  PC4   |
+ *  49             |  PC5   |
+ *  50             |  PD11  |
+ *  51             |  PD8   |
+ *  52             |  PD9   |
+ *  53             |  PD10  |
+ *  54             |  PB5   | "A8"
+ *  55             |  PB6   | "A9"
+ *  56             |  PB7   | "A10"
+ *  57             |  PB8   | "A11"
+ *  58             |  PB9   | "A12"
+ *  69             |  PA4   | "A13"
+ *  60             |  PA6   | "A14"
+ *  61             |  PA7   | "A15"
+ *  62             |  PB17  |
+ *  63             |  PB20  |
+ *  64             |  PD11  |
+ *  65             |  PD8   |
+ *  66             |  PD9   |
+ *  67             |  PA2   | "A0" / "DAC0"
+ *  68             |  PA5   | "A1" / "DAC1"
+ *  69             |  PB3   | "A2"
+ *  70             |  PC0   | "A3"
+ *  71             |  PC1   | "A4"
+ *  72             |  PC2   | "A5"
+ *  73             |  PC3   | "A6"
+ *  74             |  PB4   | "A7"
+ *  75             |  PC31  | LED GREEN "RX"
+ *  76             |  PC30  | LED GREEN "TX"
+ *  77             |  PA27  | USB: Host enable
+ *  78             |  PA24  | USB: D-
+ *  79             |  PA25  | USB: D+
+ *  80             |  PB29  | SD: MISO
+ *  81             |  PB27  | SD: SCK
+ *  82             |  PB26  | SD: MOSI
+ *  83             |  PB28  | SD: CS
+ *  84             |  PA3   | AREF
+ *  85             |  PA2   | DAC0 (Duplicate)
+ *  86             |  PA5   | DAC1 (Duplicate)
+ *  87             |  PB1   | LED AMBER "L" (Duplicate)
+ *  88             |  PC24  | NeoPixel
+ *  89             |  PB10  | QSPI: SCK
+ *  90             |  PB11  | QSPI: CS
+ *  91             |  PA8   | QSPI: IO0
+ *  92             |  PA9   | QSPI: IO1
+ *  93             |  PA10  | QSPI: IO2
+ *  94             |  PA11  | QSPI: IO3
+ *  95             |  PB31  | SD: DETECT
+ */

Marlin/src/HAL/SAMD21/spi_pins.h

@@ -0,0 +1,54 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+/**
+ * SAMD21 Default SPI Pins
+ *
+ *         SS    SCK   MISO   MOSI
+ *       +-------------------------+
+ *  SPI  | 53    52     50     51  |
+ *  SPI1 | 83    81     80     82  |
+ *       +-------------------------+
+ * Any pin can be used for Chip Select (SD_SS_PIN)
+ */
+#ifndef SD_SCK_PIN
+  #define SD_SCK_PIN    38
+#endif
+#ifndef SD_MISO_PIN
+  #define SD_MISO_PIN   36
+#endif
+#ifndef SD_MOSI_PIN
+  #define SD_MOSI_PIN   37
+#endif
+#ifndef SDSS
+  #define SDSS          18
+#endif
+
+#ifndef SD_SS_PIN
+  #define SD_SS_PIN     SDSS
+#endif

Marlin/src/HAL/SAMD21/timers.cpp

@@ -0,0 +1,217 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#ifdef __SAMD21__
+
+// --------------------------------------------------------------------------
+// Includes
+// --------------------------------------------------------------------------
+
+#include "../../inc/MarlinConfig.h"
+#include "ServoTimers.h" // for SERVO_TC
+
+// --------------------------------------------------------------------------
+// Local defines
+// --------------------------------------------------------------------------
+
+#define NUM_HARDWARE_TIMERS 9
+
+// --------------------------------------------------------------------------
+// Private Variables
+// --------------------------------------------------------------------------
+
+const tTimerConfig timer_config[NUM_HARDWARE_TIMERS] = {
+  { {.pTcc=TCC0}, TimerType::tcc,  TCC0_IRQn, TC_PRIORITY(0) },  // 0 - stepper (assigned priority 2)
+  { {.pTcc=TCC1}, TimerType::tcc,  TCC1_IRQn, TC_PRIORITY(1) },  // 1 - stepper (needed by 32 bit timers)
+  { {.pTcc=TCC2}, TimerType::tcc,  TCC2_IRQn, 5              },  // 2 - tone (reserved by framework and fixed assigned priority 5)
+  { {.pTc=TC3},   TimerType::tc,   TC3_IRQn,  TC_PRIORITY(3) },  // 3 - servo (assigned priority 1)
+  { {.pTc=TC4},   TimerType::tc,   TC4_IRQn,  TC_PRIORITY(4) },  // 4 - software serial (no interrupts used)
+  { {.pTc=TC5},   TimerType::tc,   TC5_IRQn,  TC_PRIORITY(5) },
+  { {.pTc=TC6},   TimerType::tc,   TC6_IRQn,  TC_PRIORITY(6) },
+  { {.pTc=TC7},   TimerType::tc,   TC7_IRQn,  TC_PRIORITY(7) },
+  { {.pRtc=RTC},  TimerType::rtc,   RTC_IRQn, TC_PRIORITY(8) }   // 8 - temperature (assigned priority 6)
+};
+
+// --------------------------------------------------------------------------
+// Private functions
+// --------------------------------------------------------------------------
+
+FORCE_INLINE void Disable_Irq(IRQn_Type irq) {
+  NVIC_DisableIRQ(irq);
+
+  // We NEED memory barriers to ensure Interrupts are actually disabled!
+  // ( https://dzone.com/articles/nvic-disabling-interrupts-on-arm-cortex-m-and-the )
+  __DSB();
+  __ISB();
+}
+
+static bool tcIsSyncing(Tc * tc) {
+  return tc->COUNT32.STATUS.reg & TC_STATUS_SYNCBUSY;
+}
+
+static void tcReset( Tc * tc) {
+  tc->COUNT32.CTRLA.reg = TC_CTRLA_SWRST;
+  while (tcIsSyncing(tc)) {}
+  while (tc->COUNT32.CTRLA.bit.SWRST) {}
+}
+
+// --------------------------------------------------------------------------
+// Public functions
+// --------------------------------------------------------------------------
+
+void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {
+  IRQn_Type irq = timer_config[timer_num].IRQ_Id;
+
+  // Disable interrupt, just in case it was already enabled
+  NVIC_DisableIRQ(irq);
+  NVIC_ClearPendingIRQ(irq);
+
+  if (timer_num == MF_TIMER_RTC) {
+
+    // https://github.com/arduino-libraries/RTCZero
+    Rtc * const rtc = timer_config[timer_num].pRtc;
+    PM->APBAMASK.reg |= PM_APBAMASK_RTC;
+
+    GCLK->CLKCTRL.reg = (uint32_t)((GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK4 | (RTC_GCLK_ID << GCLK_CLKCTRL_ID_Pos)));
+    while (GCLK->STATUS.bit.SYNCBUSY) {}
+
+    GCLK->GENCTRL.reg = (GCLK_GENCTRL_GENEN | GCLK_GENCTRL_SRC_OSCULP32K | GCLK_GENCTRL_ID(4) | GCLK_GENCTRL_DIVSEL );
+    while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY) {}
+
+    GCLK->GENDIV.reg = GCLK_GENDIV_ID(4);
+    GCLK->GENDIV.bit.DIV=4;
+    while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY) {}
+
+    // Disable timer interrupt
+    rtc->MODE0.INTENCLR.reg = RTC_MODE0_INTENCLR_CMP0;
+    SYNC(rtc->MODE0.STATUS.bit.SYNCBUSY);
+
+    while(rtc->MODE0.STATUS.bit.SYNCBUSY) {}
+
+    // Stop timer, just in case, to be able to reconfigure it
+    rtc->MODE0.CTRL.reg =
+      RTC_MODE0_CTRL_MODE_COUNT32 |           // Mode 0 = 32-bits counter
+      RTC_MODE0_CTRL_PRESCALER_DIV1024;       // Divisor = 1024
+
+    while(rtc->MODE0.STATUS.bit.SYNCBUSY) {}
+
+    // Mode, reset counter on match
+    rtc->MODE0.CTRL.reg = RTC_MODE0_CTRL_MODE_COUNT32 | RTC_MODE0_CTRL_MATCHCLR;
+
+    // Set compare value
+    rtc->MODE0.COMP[0].reg = (32768 + frequency / 2) / frequency;
+    SYNC(rtc->MODE0.STATUS.bit.SYNCBUSY);
+
+    // Enable interrupt on compare
+    rtc->MODE0.INTFLAG.reg = RTC_MODE0_INTFLAG_CMP0;    // reset pending interrupt
+    rtc->MODE0.INTENSET.reg = RTC_MODE0_INTENSET_CMP0;  // enable compare 0 interrupt
+
+    // And start timer
+    rtc->MODE0.CTRL.bit.ENABLE = true;
+    SYNC(rtc->MODE0.STATUS.bit.SYNCBUSY);
+
+  }
+  else if (timer_config[timer_num].type==TimerType::tcc) {
+    
+    Tcc * const tc = timer_config[timer_num].pTcc;
+
+    PM->APBCMASK.reg |= PM_APBCMASK_TCC0;
+     GCLK->CLKCTRL.reg =(GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_ID(TCC0_GCLK_ID));
+    SYNC (GCLK->STATUS.bit.SYNCBUSY);
+
+    tc->CTRLA.reg = TCC_CTRLA_SWRST;
+    SYNC (tc->SYNCBUSY.reg & TCC_SYNCBUSY_SWRST) {}
+
+    SYNC (tc->CTRLA.bit.SWRST);
+
+    tc->CTRLA.reg &= ~(TCC_CTRLA_ENABLE);       // disable TC module
+
+    tc->CTRLA.reg |= TCC_WAVE_WAVEGEN_MFRQ;
+    tc->CTRLA.reg |= TCC_CTRLA_PRESCALER_DIV2;
+    tc->CC[0].reg = (HAL_TIMER_RATE) / frequency;
+    tc->INTENSET.reg = TCC_INTFLAG_MC0;
+    tc->CTRLA.reg |= TCC_CTRLA_ENABLE;
+    tc->INTFLAG.reg = 0xFF;
+    SYNC ( tc->STATUS.reg & TC_STATUS_SYNCBUSY);
+
+  }
+  else {
+    Tc * const tc = timer_config[timer_num].pTc;
+
+    // Disable timer interrupt
+    tc->COUNT32.INTENCLR.reg = TC_INTENCLR_OVF; // disable overflow interrupt
+
+    // TCn clock setup
+    GCLK->CLKCTRL.reg = (uint16_t) (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0  | GCLK_CLKCTRL_ID(GCM_TC4_TC5)) ;
+    SYNC (GCLK->STATUS.bit.SYNCBUSY);
+
+    tcReset(tc); // reset TC
+
+    // Set Timer counter 5 Mode to 16 bits, it will become a 16bit counter ('mode1' in the datasheet)
+    tc->COUNT32.CTRLA.reg |= TC_CTRLA_MODE_COUNT32;
+    // Set TC waveform generation mode to 'match frequency'
+    tc->COUNT32.CTRLA.reg |= TC_CTRLA_WAVEGEN_MFRQ;
+    //set prescaler
+    //the clock normally counts at the GCLK_TC frequency, but we can set it to divide that frequency to slow it down
+    //you can use different prescaler divisons here like TC_CTRLA_PRESCALER_DIV1 to get a different range
+    tc->COUNT32.CTRLA.reg |= TC_CTRLA_PRESCALER_DIV1 | TC_CTRLA_ENABLE; //it will divide GCLK_TC frequency by 1024
+    //set the compare-capture register.
+    //The counter will count up to this value (it's a 16bit counter so we use uint16_t)
+    //this is how we fine-tune the frequency, make it count to a lower or higher value
+    //system clock should be 1MHz (8MHz/8) at Reset by default
+    tc->COUNT32.CC[0].reg = (uint16_t) (HAL_TIMER_RATE / frequency);
+    while (tcIsSyncing(tc)) {}
+
+    // Enable the TC interrupt request
+    tc->COUNT32.INTENSET.bit.MC0 = 1;
+    while (tcIsSyncing(tc)) {}
+  }
+
+  NVIC_SetPriority(irq, timer_config[timer_num].priority);
+  NVIC_EnableIRQ(irq);
+}
+
+void HAL_timer_enable_interrupt(const uint8_t timer_num) {
+  const IRQn_Type irq = timer_config[timer_num].IRQ_Id;
+  NVIC_EnableIRQ(irq);
+}
+
+void HAL_timer_disable_interrupt(const uint8_t timer_num) {
+  const IRQn_Type irq = timer_config[timer_num].IRQ_Id;
+  Disable_Irq(irq);
+}
+
+// missing from CMSIS: Check if interrupt is enabled or not
+static bool NVIC_GetEnabledIRQ(IRQn_Type IRQn) {
+  return TEST(NVIC->ISER[uint32_t(IRQn) >> 5], uint32_t(IRQn) & 0x1F);
+}
+
+bool HAL_timer_interrupt_enabled(const uint8_t timer_num) {
+  const IRQn_Type irq = timer_config[timer_num].IRQ_Id;
+  return NVIC_GetEnabledIRQ(irq);
+}
+
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/timers.h

@@ -0,0 +1,160 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+
+#include <stdint.h>
+
+// --------------------------------------------------------------------------
+// Defines
+// --------------------------------------------------------------------------
+
+typedef uint32_t hal_timer_t;
+#define HAL_TIMER_TYPE_MAX 0xFFFFFFFF
+
+#define HAL_TIMER_RATE      F_CPU   // frequency of timers peripherals
+
+#define MF_TIMER_RTC            8   // This is not a TC but a RTC
+
+#ifndef MF_TIMER_STEP
+  #define MF_TIMER_STEP         4   // Timer Index for Stepper
+#endif
+#ifndef MF_TIMER_PULSE
+  #define MF_TIMER_PULSE        MF_TIMER_STEP
+#endif
+#ifndef MF_TIMER_TEMP
+  #define MF_TIMER_TEMP         MF_TIMER_RTC // Timer Index for Temperature
+#endif
+
+#define TEMP_TIMER_FREQUENCY   1000 // temperature interrupt frequency
+
+#define STEPPER_TIMER_RATE          HAL_TIMER_RATE   // frequency of stepper timer (HAL_TIMER_RATE / STEPPER_TIMER_PRESCALE)
+#define STEPPER_TIMER_TICKS_PER_US  (STEPPER_TIMER_RATE / 1000000) // stepper timer ticks per µs
+#define STEPPER_TIMER_PRESCALE      (CYCLES_PER_MICROSECOND / STEPPER_TIMER_TICKS_PER_US)
+
+#define PULSE_TIMER_RATE          STEPPER_TIMER_RATE
+#define PULSE_TIMER_PRESCALE      STEPPER_TIMER_PRESCALE
+#define PULSE_TIMER_TICKS_PER_US  STEPPER_TIMER_TICKS_PER_US
+
+#define ENABLE_STEPPER_DRIVER_INTERRUPT()   HAL_timer_enable_interrupt(MF_TIMER_STEP)
+#define DISABLE_STEPPER_DRIVER_INTERRUPT()  HAL_timer_disable_interrupt(MF_TIMER_STEP)
+#define STEPPER_ISR_ENABLED()               HAL_timer_interrupt_enabled(MF_TIMER_STEP)
+
+#define ENABLE_TEMPERATURE_INTERRUPT()  HAL_timer_enable_interrupt(MF_TIMER_TEMP)
+#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(MF_TIMER_TEMP)
+
+#define TC_PRIORITY(t) (  t == SERVO_TC ? 1                              \
+                       : (t == MF_TIMER_STEP || t == MF_TIMER_PULSE) ? 2 \
+                       : (t == MF_TIMER_TEMP) ? 6 : 7 )
+
+#define _TC_HANDLER(t)          void TC##t##_Handler()
+#define TC_HANDLER(t)           _TC_HANDLER(t)
+#ifndef HAL_STEP_TIMER_ISR
+  #define HAL_STEP_TIMER_ISR()  TC_HANDLER(MF_TIMER_STEP)
+#endif
+#if MF_TIMER_STEP != MF_TIMER_PULSE
+  #define HAL_PULSE_TIMER_ISR() TC_HANDLER(MF_TIMER_PULSE)
+#endif
+#if MF_TIMER_TEMP == MF_TIMER_RTC
+  #define HAL_TEMP_TIMER_ISR()  void RTC_Handler()
+#else
+  #define HAL_TEMP_TIMER_ISR()  TC_HANDLER(MF_TIMER_TEMP)
+#endif
+
+// --------------------------------------------------------------------------
+// Types
+// --------------------------------------------------------------------------
+typedef enum  { tcc, tc, rtc } TimerType;
+
+typedef struct {
+  union {
+    Tc  *pTc;
+    Tcc *pTcc;
+    Rtc *pRtc;
+  };
+  TimerType type;
+  IRQn_Type   IRQ_Id;
+  uint8_t     priority;
+} tTimerConfig;
+
+// --------------------------------------------------------------------------
+// Public Variables
+// --------------------------------------------------------------------------
+
+extern const tTimerConfig timer_config[];
+
+// --------------------------------------------------------------------------
+// Public functions
+// --------------------------------------------------------------------------
+
+void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency);
+
+FORCE_INLINE static void HAL_timer_set_compare(const uint8_t timer_num, const hal_timer_t compare) {
+  // Should never be called with timer MF_TIMER_RTC
+  Tc * const tc = timer_config[timer_num].pTc;
+  tc->COUNT32.CC[0].reg = compare;
+}
+
+FORCE_INLINE static hal_timer_t HAL_timer_get_compare(const uint8_t timer_num) {
+  // Should never be called with timer MF_TIMER_RTC
+  Tc * const tc = timer_config[timer_num].pTc;
+  return (hal_timer_t)tc->COUNT32.CC[0].reg;
+}
+
+FORCE_INLINE static hal_timer_t HAL_timer_get_count(const uint8_t timer_num) {
+  // Should never be called with timer MF_TIMER_RTC
+  Tc * const tc = timer_config[timer_num].pTc;
+  tc->COUNT32.READREQ.reg = TC_READREQ_RREQ;
+  // Request a read synchronization
+  SYNC (tc->COUNT32.STATUS.bit.SYNCBUSY);
+  //SYNC(tc->COUNT32.STATUS.bit.SYNCBUSY );
+  return tc->COUNT32.COUNT.reg;
+}
+
+void HAL_timer_enable_interrupt(const uint8_t timer_num);
+void HAL_timer_disable_interrupt(const uint8_t timer_num);
+bool HAL_timer_interrupt_enabled(const uint8_t timer_num);
+
+FORCE_INLINE static void HAL_timer_isr_prologue(const uint8_t timer_num) {
+  if (timer_num == MF_TIMER_RTC) {
+    Rtc * const rtc = timer_config[timer_num].pRtc;
+    // Clear interrupt flag
+    rtc->MODE0.INTFLAG.reg = RTC_MODE0_INTFLAG_CMP0| RTC_MODE0_INTFLAG_OVF;
+
+  }
+  else if (timer_config[timer_num].type == TimerType::tcc){
+    Tcc * const tc = timer_config[timer_num].pTcc;
+    // Clear interrupt flag
+    tc->INTFLAG.reg = TCC_INTFLAG_OVF;
+  }
+  else {
+    Tc * const tc = timer_config[timer_num].pTc;
+    // Clear interrupt flag
+    tc->COUNT32.INTFLAG.bit.MC0 = 1;
+  }
+}
+
+#define HAL_timer_isr_epilogue(timer_num)

Marlin/src/HAL/SAMD21/u8g/LCD_I2C_routines.cpp

@@ -0,0 +1,32 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+// adapted from  I2C/master/master.c example
+//   https://www-users.cs.york.ac.uk/~pcc/MCP/HAPR-Course-web/CMSIS/examples/html/master_8c_source.html
+
+#ifdef __SAMD21__
+
+#endif // __SAMD21__

Marlin/src/HAL/SAMD21/u8g/LCD_I2C_routines.h

@@ -0,0 +1,27 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * SAMD21 HAL developed by Bart Meijer (brupje)
+ * Based on SAMD51 HAL by Giuliano Zaro (AKA GMagician)
+ */
+#pragma once