diff --git a/Marlin/src/HAL/AVR/fastio/fastio_1280.h b/Marlin/src/HAL/AVR/fastio/fastio_1280.h
index f482f823e8..e6ecbabb80 100644
--- a/Marlin/src/HAL/AVR/fastio/fastio_1280.h
+++ b/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"
diff --git a/Marlin/src/HAL/AVR/fastio/fastio_1281.h b/Marlin/src/HAL/AVR/fastio/fastio_1281.h
index e0bc5e2995..812586225d 100644
--- a/Marlin/src/HAL/AVR/fastio/fastio_1281.h
+++ b/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"
diff --git a/Marlin/src/HAL/AVR/fastio/fastio_168.h b/Marlin/src/HAL/AVR/fastio/fastio_168.h
index 8cfdd1e8f8..4f591b37b9 100644
--- a/Marlin/src/HAL/AVR/fastio/fastio_168.h
+++ b/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"
diff --git a/Marlin/src/HAL/AVR/fastio/fastio_644.h b/Marlin/src/HAL/AVR/fastio/fastio_644.h
index f4a9427e0a..16bdc6a23d 100644
--- a/Marlin/src/HAL/AVR/fastio/fastio_644.h
+++ b/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
diff --git a/Marlin/src/HAL/AVR/fastio/fastio_AT90USB.h b/Marlin/src/HAL/AVR/fastio/fastio_AT90USB.h
index 51d400b705..d2a8aca6f3 100644
--- a/Marlin/src/HAL/AVR/fastio/fastio_AT90USB.h
+++ b/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"
diff --git a/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_I2C_routines.h b/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_I2C_routines.h
index 6d5f91d3ba..ec263b6dd3 100644
--- a/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_I2C_routines.h
+++ b/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_I2C_routines.h
@@ -34,4 +34,3 @@ void u8g_i2c_stop();
 #ifdef __cplusplus
   }
 #endif
-
diff --git a/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_defines.h b/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_defines.h
index 44ffbfeb90..2a50eddcd4 100644
--- a/Marlin/src/HAL/NATIVE_SIM/u8g/LCD_defines.h
+++ b/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
-
-
diff --git a/Marlin/src/HAL/SAMD21/HAL_SPI.cpp b/Marlin/src/HAL/SAMD21/HAL_SPI.cpp
index 0fc530cdb2..69c6a43af8 100644
--- a/Marlin/src/HAL/SAMD21/HAL_SPI.cpp
+++ b/Marlin/src/HAL/SAMD21/HAL_SPI.cpp
@@ -64,7 +64,7 @@
   }
 
   void spiInit(uint8_t spiRate) {
-    // Use datarates Marlin uses
+    // Use Marlin datarates
     uint32_t clock;
     switch (spiRate) {
       case SPI_FULL_SPEED:      clock = 8000000; break;
diff --git a/Marlin/src/HAL/SAMD21/fastio.h b/Marlin/src/HAL/SAMD21/fastio.h
index db64f2166f..df907ff7ec 100644
--- a/Marlin/src/HAL/SAMD21/fastio.h
+++ b/Marlin/src/HAL/SAMD21/fastio.h
@@ -213,4 +213,3 @@
 #define DIO53_PIN   PIN_PA21
 #define DIO54_PIN   PIN_PA06
 #define DIO55_PIN   PIN_PA07
-
diff --git a/Marlin/src/pins/lpc1768/pins_AZSMZ_MINI.h b/Marlin/src/pins/lpc1768/pins_AZSMZ_MINI.h
index 4d1dbecf2e..657eb8a046 100644
--- a/Marlin/src/pins/lpc1768/pins_AZSMZ_MINI.h
+++ b/Marlin/src/pins/lpc1768/pins_AZSMZ_MINI.h
@@ -23,6 +23,8 @@
 
 /**
  * AZSMZ MINI pin assignments
+ * Schematic: http://green-candy.osdn.jp/external/MarlinFW/board_schematics/AZSMZ%20MINI/AZSMZ.svg
+ * Source: https://raw.githubusercontent.com/Rose-Fish/AZSMZ-mini/master/AZSMZ.sch
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_BIQU_B300_V1.0.h b/Marlin/src/pins/lpc1768/pins_BIQU_B300_V1.0.h
index 0c96cb42b5..7215150d0b 100644
--- a/Marlin/src/pins/lpc1768/pins_BIQU_B300_V1.0.h
+++ b/Marlin/src/pins/lpc1768/pins_BIQU_B300_V1.0.h
@@ -22,11 +22,7 @@
 #pragma once
 
 /**
- * BIQU BQ111-A4
- *
- * Applies to the following boards:
- *
- *  BOARD_BIQU_BQ111_A4 (Hotend, Fan, Bed)
+ * BIQU Thunder B300 V1.0
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_BIQU_BQ111_A4.h b/Marlin/src/pins/lpc1768/pins_BIQU_BQ111_A4.h
index 92152170a0..2c0d52ef9a 100644
--- a/Marlin/src/pins/lpc1768/pins_BIQU_BQ111_A4.h
+++ b/Marlin/src/pins/lpc1768/pins_BIQU_BQ111_A4.h
@@ -23,6 +23,10 @@
 
 /**
  * BIQU BQ111-A4 pin assignments
+ *
+ * Applies to the following boards:
+ *
+ *  BOARD_BIQU_BQ111_A4 (Hotend, Fan, Bed)
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_1.h b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_1.h
index 1a8c44771a..d1ea2c0197 100644
--- a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_1.h
+++ b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_1.h
@@ -23,6 +23,8 @@
 
 /**
  * BigTreeTech SKR 1.1 pin assignments
+ * Schematic: http://green-candy.osdn.jp/external/MarlinFW/board_schematics/BTT%20SKR%20V1.1/SKR-V1.1SchDoc.pdf
+ * Origin: https://github.com/bigtreetech/BIGTREETECH-SKR-V1.1/blob/master/hardware/SKR-V1.1SchDoc.pdf
  */
 
 #define BOARD_INFO_NAME "BTT SKR V1.1"
diff --git a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h
index 6372623a30..aafc8d3f9f 100644
--- a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h
+++ b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_3.h
@@ -23,6 +23,8 @@
 
 /**
  * BigTreeTech SKR 1.3 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/BTT%20SKR%20V1.3/SKR-V1.3-SCH.pdf
+ * Origin: https://github.com/bigtreetech/BIGTREETECH-SKR-V1.3/blob/master/BTT%20SKR%20V1.3/hardware/SKR-V1.3-SCH.pdf
  */
 
 #define BOARD_INFO_NAME "BTT SKR V1.3"
diff --git a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h
index e632d8afa6..b4fafbf7a4 100644
--- a/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h
+++ b/Marlin/src/pins/lpc1768/pins_BTT_SKR_V1_4.h
@@ -23,6 +23,8 @@
 
 /**
  * BigTreeTech SKR 1.4 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/BTT%20SKR%20V1.4%20+%20Turbo/BTT%20SKR%20V1.4-SCH.pdf
+ * Origin: https://github.com/bigtreetech/BIGTREETECH-SKR-V1.3/blob/master/BTT%20SKR%20V1.4/Hardware/BTT%20SKR%20V1.4-SCH.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_EMOTRONIC.h b/Marlin/src/pins/lpc1768/pins_EMOTRONIC.h
index 6e1ea403b1..9e62be8edb 100644
--- a/Marlin/src/pins/lpc1768/pins_EMOTRONIC.h
+++ b/Marlin/src/pins/lpc1768/pins_EMOTRONIC.h
@@ -23,6 +23,8 @@
 
 /**
  * eMotion-Tech eMotronic pin assignments
+ * Schematic: http://green-candy.osdn.jp/external/MarlinFW/board_schematics/eMotion-Tech%20eMotronic/eMotronic_brd_sources_1.0.4/eMotronic_sch.pdf
+ * Origin: https://data.emotion-tech.com/ftp/Datasheets_et_sources/Sources/eMotronic_brd_sources_1.0.4.zip
  *
  * Board pins<->features assignments are based on the
  * Micro-Delta Rework printer default connections.
diff --git a/Marlin/src/pins/lpc1768/pins_GMARSH_X6_REV1.h b/Marlin/src/pins/lpc1768/pins_GMARSH_X6_REV1.h
index 39ab0bbd89..aedbd7be60 100644
--- a/Marlin/src/pins/lpc1768/pins_GMARSH_X6_REV1.h
+++ b/Marlin/src/pins/lpc1768/pins_GMARSH_X6_REV1.h
@@ -23,6 +23,8 @@
 
 /**
  * GMARSH X6 Rev.1 pin assignments
+ * Schematic: http://green-candy.osdn.jp/external/MarlinFW/board_schematics/GMARSH%20X6%20Rev.1/armprinter_2208_1heater.pdf
+ * Origin: https://github.com/gmarsh/gmarsh_x6/blob/master/armprinter_2208_1heater.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_MKS_SBASE.h b/Marlin/src/pins/lpc1768/pins_MKS_SBASE.h
index c5c5bd3e23..14759901ac 100644
--- a/Marlin/src/pins/lpc1768/pins_MKS_SBASE.h
+++ b/Marlin/src/pins/lpc1768/pins_MKS_SBASE.h
@@ -23,6 +23,8 @@
 
 /**
  * Makerbase MKS SBASE pin assignments
+ * Schematic (V1.3): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/MKS%20SBASE%20V1.3/MKS%20SBASE%20V1.3_002%20SCH.pdf
+ * Origin (V1.3): http://green-candy.osdn.jp/external/MarlinFW/board_schematics/MKS%20SBASE%20V1.3/MKS%20SBASE%20V1.3_002%20SCH.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h b/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h
index 1f038b4aa0..1235e44ec9 100644
--- a/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h
+++ b/Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h
@@ -23,6 +23,8 @@
 
 /**
  * Makerbase MKS SGEN-L pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/MKS_GEN_L_V1_0/MKS%20Gen_L%20V1.0_008%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/SGEN_L/blob/master/Hardware/MKS%20SGEN_L%20V1.0_001/MKS%20SGEN_L%20V1.0_001%20SCH.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1768/pins_RAMPS_RE_ARM.h b/Marlin/src/pins/lpc1768/pins_RAMPS_RE_ARM.h
index b6ce9c5c05..893a8a755b 100644
--- a/Marlin/src/pins/lpc1768/pins_RAMPS_RE_ARM.h
+++ b/Marlin/src/pins/lpc1768/pins_RAMPS_RE_ARM.h
@@ -23,6 +23,8 @@
 
 /**
  * Re-ARM with RAMPS v1.4 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Re-ARM%20RAMPS%201.4/Re_ARM_Schematic.pdf
+ * Origin: https://reprap.org/mediawiki/images/f/fa/Re_ARM_Schematic.pdf
  *
  * Applies to the following boards:
  *
diff --git a/Marlin/src/pins/lpc1768/pins_SELENA_COMPACT.h b/Marlin/src/pins/lpc1768/pins_SELENA_COMPACT.h
index 2972ac7560..30cd76b9a2 100644
--- a/Marlin/src/pins/lpc1768/pins_SELENA_COMPACT.h
+++ b/Marlin/src/pins/lpc1768/pins_SELENA_COMPACT.h
@@ -23,6 +23,8 @@
 
 /**
  * Selena Compact pin assignments
+ * Pinout: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Selena%20Compact/Compact%20Pinout.pdf
+ * Origin: https://github.com/f61/Selena/blob/master/Compact%20Pinout.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_GT.h b/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_GT.h
index bc7cada8da..a9c61cb8c9 100644
--- a/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_GT.h
+++ b/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_GT.h
@@ -23,6 +23,8 @@
 
 /**
  * Azteeg X5 GT pin assignments
+ * Wiring diagram: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Azteeg%20X5%20GT/X5%20GT%20Wiring%20Diagram.pdf
+ * Origin: https://panucattdevices.freshdesk.com/support/solutions/articles/1000244740-support-files
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI.h b/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI.h
index c33fe6e28f..eabb338504 100644
--- a/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI.h
+++ b/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI.h
@@ -23,6 +23,10 @@
 
 /**
  * Azteeg X5 MINI pin assignments
+ * Schematic (V1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Azteeg%20X5%20MINI/x5mini_design_files/X5mini_design_files/V1/X5%20Mini%20PUB%20v1.0.pdf
+ * Schematic (V2): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Azteeg%20X5%20MINI/x5mini_design_files/X5mini_design_files/V2/X5%20Mini%20V2%20SCH%20Pub.pdf
+ * Schematic (V3): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Azteeg%20X5%20MINI/x5mini_design_files/X5mini_design_files/V3/X5%20Mini%20V3%20SCH%20Pub.pdf
+ * Origin: http://files.panucatt.com/datasheets/x5mini_design_files.zip
  */
 #include "env_validate.h"
 
diff --git a/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI_WIFI.h b/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI_WIFI.h
index 086bacbac0..74439e4f3d 100644
--- a/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI_WIFI.h
+++ b/Marlin/src/pins/lpc1769/pins_AZTEEG_X5_MINI_WIFI.h
@@ -23,6 +23,8 @@
 
 /**
  * Azteeg X5 MINI WIFI pin assignments
+ * Wiring diagram: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Azteeg%20X5%20MINI%20WIFI/x5mini_wifi_wiring.pdf
+ * Origin: http://files.panucatt.com/datasheets/x5mini_wifi_wiring.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_BTT_SKR_E3_TURBO.h b/Marlin/src/pins/lpc1769/pins_BTT_SKR_E3_TURBO.h
index dbaafb89cc..f62818dd9f 100644
--- a/Marlin/src/pins/lpc1769/pins_BTT_SKR_E3_TURBO.h
+++ b/Marlin/src/pins/lpc1769/pins_BTT_SKR_E3_TURBO.h
@@ -23,6 +23,8 @@
 
 /**
  * BigTreeTech SKR E3 Turbo pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/BTT%20SKR%20E3%20Turbo/BTT%20SKR%20E3%20Turbo-SCH.pdf
+ * Origin: https://github.com/bigtreetech/BIGTREETECH-SKR-E3-Turbo/blob/master/Hardware/BTT%20SKR%20E3%20Turbo-SCH.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_BTT_SKR_V1_4_TURBO.h b/Marlin/src/pins/lpc1769/pins_BTT_SKR_V1_4_TURBO.h
index 7f428fc918..1bd70d8fb5 100644
--- a/Marlin/src/pins/lpc1769/pins_BTT_SKR_V1_4_TURBO.h
+++ b/Marlin/src/pins/lpc1769/pins_BTT_SKR_V1_4_TURBO.h
@@ -23,6 +23,8 @@
 
 /**
  * BigTreeTech SKR 1.4 Turbo pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/BTT%20SKR%20V1.4%20+%20Turbo/BTT%20SKR%20V1.4-SCH.pdf
+ * Origin: https://github.com/bigtreetech/BIGTREETECH-SKR-V1.3/blob/master/BTT%20SKR%20V1.4/Hardware/BTT%20SKR%20V1.4-SCH.pdf
  */
 
 #define BOARD_INFO_NAME "BTT SKR V1.4 TURBO"
diff --git a/Marlin/src/pins/lpc1769/pins_COHESION3D_MINI.h b/Marlin/src/pins/lpc1769/pins_COHESION3D_MINI.h
index e0a3b03109..5c9355de29 100644
--- a/Marlin/src/pins/lpc1769/pins_COHESION3D_MINI.h
+++ b/Marlin/src/pins/lpc1769/pins_COHESION3D_MINI.h
@@ -23,6 +23,8 @@
 
 /**
  * Cohesion3D Mini pin assignments
+ * Pinout: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Cohesion3D%20Mini/c3d-pinout.jpg
+ * Origin: https://lasergods.com/cohesion3d-mini-pinout-diagram/
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_COHESION3D_REMIX.h b/Marlin/src/pins/lpc1769/pins_COHESION3D_REMIX.h
index 122c7462d2..5083a0ed48 100644
--- a/Marlin/src/pins/lpc1769/pins_COHESION3D_REMIX.h
+++ b/Marlin/src/pins/lpc1769/pins_COHESION3D_REMIX.h
@@ -23,6 +23,8 @@
 
 /**
  * Cohesion3D ReMix pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Cohesion3D%20ReMix/C3D%20ReMix%20rev2.svg
+ * Origin: https://github.com/Cohesion3D/Cohesion3D-ReMix/blob/master/C3D%20ReMix%20rev2.sch
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_FLY_CDY.h b/Marlin/src/pins/lpc1769/pins_FLY_CDY.h
index 1c0c21466e..ed0ce30eb3 100644
--- a/Marlin/src/pins/lpc1769/pins_FLY_CDY.h
+++ b/Marlin/src/pins/lpc1769/pins_FLY_CDY.h
@@ -23,6 +23,8 @@
 
 /**
  * FLYmaker FLY-CDY pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/FLYmaker%20FLY-CDY%20V1/FLY_CDY%20SCH.pdf
+ * Origin: https://github.com/Mellow-3D/FLY-CDY/blob/master/Motherboard%20information/FLY_CDY%20SCH.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_MKS_SGEN.h b/Marlin/src/pins/lpc1769/pins_MKS_SGEN.h
index 23bcecc78d..1e71fccfe5 100644
--- a/Marlin/src/pins/lpc1769/pins_MKS_SGEN.h
+++ b/Marlin/src/pins/lpc1769/pins_MKS_SGEN.h
@@ -23,6 +23,8 @@
 
 /**
  * MKS SGen pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/MKS%20SGEN/MKS%20SGEN%20V1.0_001%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/MKS-SGen/blob/master/Hardware/MKS%20SGEN%20V1.0_001/MKS%20SGEN%20V1.0_001%20SCH.pdf
  *
  * Pins diagram:
  * https://github.com/makerbase-mks/MKS-SGen/blob/master/Hardware/MKS%20SGEN%20V1.0_001/MKS%20SGEN%20V1.0_001%20PIN.pdf
diff --git a/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h b/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h
index 5c1b1f5638..54b771d318 100644
--- a/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h
+++ b/Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h
@@ -23,6 +23,8 @@
 
 /**
  * MKS SGen-L V2 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/MKS%20SGEN_L%20V2/MKS%20SGEN_L%20V2.0_003%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/MKS-SGEN_L-V2/blob/master/Hardware/MKS%20SGEN_L%20V2.0_003/MKS%20SGEN_L%20V2.0_003%20SCH.pdf
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/lpc1769/pins_SMOOTHIEBOARD.h b/Marlin/src/pins/lpc1769/pins_SMOOTHIEBOARD.h
index cfaca164f8..124c8f63c2 100644
--- a/Marlin/src/pins/lpc1769/pins_SMOOTHIEBOARD.h
+++ b/Marlin/src/pins/lpc1769/pins_SMOOTHIEBOARD.h
@@ -23,6 +23,8 @@
 
 /**
  * Smoothieware Smoothieboard pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Smoothieware%20Smoothieboard%20V1/http.i.imgur.com.oj4zqs3.png
+ * Origin: http://smoothieware.org/_media///external/http.i.imgur.com.oj4zqs3.png
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_CHEAPTRONIC.h b/Marlin/src/pins/mega/pins_CHEAPTRONIC.h
index 8bcb263bc1..e95f6c4ade 100644
--- a/Marlin/src/pins/mega/pins_CHEAPTRONIC.h
+++ b/Marlin/src/pins/mega/pins_CHEAPTRONIC.h
@@ -23,6 +23,7 @@
 
 /**
  * Cheaptronic v1.0 pin assignments
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_CHEAPTRONICv2.h b/Marlin/src/pins/mega/pins_CHEAPTRONICv2.h
index 01438975b9..e81295a653 100644
--- a/Marlin/src/pins/mega/pins_CHEAPTRONICv2.h
+++ b/Marlin/src/pins/mega/pins_CHEAPTRONICv2.h
@@ -24,7 +24,9 @@
 /**
  * Cheaptronic v2.0 pin assignments
  * Built and sold by Michal Dyntar - RRO
- *          www.reprapobchod.cz
+ *          www.reprapobchod.cz (DOES NOT EXIST ANYMORE)
+ *          https://web.archive.org/web/20190306201523/http://reprapobchod.cz/
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_CNCONTROLS_11.h b/Marlin/src/pins/mega/pins_CNCONTROLS_11.h
index 5f7a534d11..d996635c8c 100644
--- a/Marlin/src/pins/mega/pins_CNCONTROLS_11.h
+++ b/Marlin/src/pins/mega/pins_CNCONTROLS_11.h
@@ -23,6 +23,9 @@
 
 /**
  * CartesioV11 pin assignments
+ * Comes with an Arduino Mega, see
+ * https://web.archive.org/web/20171024190029/http://mauk.cc/mediawiki/index.php/Electronical_assembly
+ * ATmega2560, ATmega1280
  */
 
 #define ALLOW_MEGA1280
diff --git a/Marlin/src/pins/mega/pins_CNCONTROLS_12.h b/Marlin/src/pins/mega/pins_CNCONTROLS_12.h
index 0aa0b59ca9..ea82fe429c 100644
--- a/Marlin/src/pins/mega/pins_CNCONTROLS_12.h
+++ b/Marlin/src/pins/mega/pins_CNCONTROLS_12.h
@@ -23,6 +23,9 @@
 
 /**
  * CartesioV12 pin assignments
+ * Comes with an Arduino Mega, see
+ * https://web.archive.org/web/20171024190029/http://mauk.cc/mediawiki/index.php/Electronical_assembly
+ * ATmega2560, ATmega1280
  */
 
 #define ALLOW_MEGA1280
diff --git a/Marlin/src/pins/mega/pins_CNCONTROLS_15.h b/Marlin/src/pins/mega/pins_CNCONTROLS_15.h
index 6de3b7172e..c77e711f9c 100644
--- a/Marlin/src/pins/mega/pins_CNCONTROLS_15.h
+++ b/Marlin/src/pins/mega/pins_CNCONTROLS_15.h
@@ -23,6 +23,7 @@
 
 /**
  * CNControls V15 for HMS434 pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #define ALLOW_MEGA1280
diff --git a/Marlin/src/pins/mega/pins_EINSTART-S.h b/Marlin/src/pins/mega/pins_EINSTART-S.h
index c8cbee6740..274684f337 100644
--- a/Marlin/src/pins/mega/pins_EINSTART-S.h
+++ b/Marlin/src/pins/mega/pins_EINSTART-S.h
@@ -23,6 +23,7 @@
 
 /**
  * Einstart-S pin assignments
+ * ATmega2560, ATmega1280
  * PCB Silkscreen: 3DPrinterCon_v3.5
  */
 
diff --git a/Marlin/src/pins/mega/pins_ELEFU_3.h b/Marlin/src/pins/mega/pins_ELEFU_3.h
index f5e146cff9..6cf9e1b4e1 100644
--- a/Marlin/src/pins/mega/pins_ELEFU_3.h
+++ b/Marlin/src/pins/mega/pins_ELEFU_3.h
@@ -23,6 +23,9 @@
 
 /**
  * Elefu RA Board Pin Assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Elefu%20Ra%20v3/schematic.pdf
+ * Origin: https://github.com/kiyoshigawa/Elefu-RAv3/blob/master/RA_Circuits.zip
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_GT2560_REV_A.h b/Marlin/src/pins/mega/pins_GT2560_REV_A.h
index 99e8704ea5..bb251dfb4e 100644
--- a/Marlin/src/pins/mega/pins_GT2560_REV_A.h
+++ b/Marlin/src/pins/mega/pins_GT2560_REV_A.h
@@ -25,6 +25,9 @@
  * Geeetech GT2560 Revision A board pin assignments, based on the work of
  * George Robles (https://georges3dprinters.com) and
  * Richard Smith <galorin@gmail.com>
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Geeetech%20GT2560%20Revision%20A/GT2560_sch.pdf
+ * Origin: https://www.geeetech.com/wiki/images/9/90/GT2560_sch.pdf
+ * ATmega2560
  */
 
 #define ALLOW_MEGA1280
diff --git a/Marlin/src/pins/mega/pins_GT2560_REV_A_PLUS.h b/Marlin/src/pins/mega/pins_GT2560_REV_A_PLUS.h
index 7e2ce20c67..a982a0e00e 100644
--- a/Marlin/src/pins/mega/pins_GT2560_REV_A_PLUS.h
+++ b/Marlin/src/pins/mega/pins_GT2560_REV_A_PLUS.h
@@ -23,6 +23,9 @@
 
 /**
  * Geeetech GT2560 Revision A+ board pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Geeetech%20GT2560%20Revision%20A+/Hardware_GT2560_RevA+.pdf
+ * Origin: https://www.geeetech.com/wiki/images/d/d3/Hardware_GT2560_RevA%2B.pdf
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "GT2560 Rev.A+"
diff --git a/Marlin/src/pins/mega/pins_GT2560_REV_B.h b/Marlin/src/pins/mega/pins_GT2560_REV_B.h
index be71ec4902..0702d14eb8 100644
--- a/Marlin/src/pins/mega/pins_GT2560_REV_B.h
+++ b/Marlin/src/pins/mega/pins_GT2560_REV_B.h
@@ -23,6 +23,9 @@
 
 /**
  * Geeetech GT2560 Rev B Pins
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Geeetech%20GT2560%20Rev%20B/GT2560_REVB.pdf
+ * Origin: https://www.geeetech.com/wiki/images/7/72/GT2560_REVB.pdf
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "GT2560 Rev B"
diff --git a/Marlin/src/pins/mega/pins_GT2560_V3.h b/Marlin/src/pins/mega/pins_GT2560_V3.h
index 46b4ebf428..5d2436b684 100644
--- a/Marlin/src/pins/mega/pins_GT2560_V3.h
+++ b/Marlin/src/pins/mega/pins_GT2560_V3.h
@@ -23,6 +23,9 @@
 
 /**
  * Geeetech GT2560 3.0/3.1 pin assignments
+ * Schematic (3.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Geeetech%20GT2560%203.0/GT2560_V3.0_SCH.pdf
+ * Origin (3.0): https://github.com/Geeetech3D/Diagram/blob/master/GT2560_V3.0_SCH.pdf
+ * ATmega2560
  *
  * Also GT2560 RevB and GT2560 4.0/4.1
  */
diff --git a/Marlin/src/pins/mega/pins_GT2560_V3_A20.h b/Marlin/src/pins/mega/pins_GT2560_V3_A20.h
index c96431141c..628f897b0c 100644
--- a/Marlin/src/pins/mega/pins_GT2560_V3_A20.h
+++ b/Marlin/src/pins/mega/pins_GT2560_V3_A20.h
@@ -23,6 +23,7 @@
 
 /**
  * Geeetech A20M board pin assignments
+ * ATmega2560
  */
 
 #define LCD_PINS_RS                            5
diff --git a/Marlin/src/pins/mega/pins_GT2560_V3_MC2.h b/Marlin/src/pins/mega/pins_GT2560_V3_MC2.h
index e683d4dfda..70854c5716 100644
--- a/Marlin/src/pins/mega/pins_GT2560_V3_MC2.h
+++ b/Marlin/src/pins/mega/pins_GT2560_V3_MC2.h
@@ -23,6 +23,7 @@
 
 /**
  * Geeetech GT2560 V 3.0 board pin assignments (for Mecreator 2)
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "GT2560 V3.0 (MC2)"
diff --git a/Marlin/src/pins/mega/pins_GT2560_V4.h b/Marlin/src/pins/mega/pins_GT2560_V4.h
index 6ac07b70bf..98f503886f 100644
--- a/Marlin/src/pins/mega/pins_GT2560_V4.h
+++ b/Marlin/src/pins/mega/pins_GT2560_V4.h
@@ -23,6 +23,9 @@
 
 /**
  * Geeetech GT2560 V4.X Pins
+ * Schematic (4.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Geeetech%20GT2560%20V4.x%20+%20A20/GT2560V4.0SCHA20T.pdf
+ * Schematic (4.1B): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Geeetech%20GT2560%20V4.x%20+%20A20/GT2560V4.1BSCHA20T.pdf
+ * Origin: https://www.geeetech.com/download.html?spm=a2g0s.imconversation.0.0.22d23e5fXlQBWv&download_id=45
  */
 
 #define BOARD_INFO_NAME "GT2560 4.x"
diff --git a/Marlin/src/pins/mega/pins_GT2560_V4_A20.h b/Marlin/src/pins/mega/pins_GT2560_V4_A20.h
index c87c11e175..8ca2d44db9 100644
--- a/Marlin/src/pins/mega/pins_GT2560_V4_A20.h
+++ b/Marlin/src/pins/mega/pins_GT2560_V4_A20.h
@@ -23,6 +23,7 @@
 
 /**
  * Geeetech A20 GT2560 V4.x board pin assignments
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "GT2560 4.x"
diff --git a/Marlin/src/pins/mega/pins_HJC2560C_REV2.h b/Marlin/src/pins/mega/pins_HJC2560C_REV2.h
index 5c3b1dc9f6..1b3b7b29af 100644
--- a/Marlin/src/pins/mega/pins_HJC2560C_REV2.h
+++ b/Marlin/src/pins/mega/pins_HJC2560C_REV2.h
@@ -23,6 +23,7 @@
 
 /**
  * Geeetech HJC2560-C Rev 2.x board pin assignments
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_INTAMSYS40.h b/Marlin/src/pins/mega/pins_INTAMSYS40.h
index 2e2a9b85db..ec466fb09f 100644
--- a/Marlin/src/pins/mega/pins_INTAMSYS40.h
+++ b/Marlin/src/pins/mega/pins_INTAMSYS40.h
@@ -23,6 +23,7 @@
 
 /**
  * Intamsys Funmat HT V4.0 Mainboard
+ * ATmega2560
  * 4988 Drivers Tested
  * 2208 version exists and may or may not work
  */
diff --git a/Marlin/src/pins/mega/pins_LEAPFROG.h b/Marlin/src/pins/mega/pins_LEAPFROG.h
index 4700fd6729..3762ea98f0 100644
--- a/Marlin/src/pins/mega/pins_LEAPFROG.h
+++ b/Marlin/src/pins/mega/pins_LEAPFROG.h
@@ -23,6 +23,7 @@
 
 /**
  * Leapfrog Driver board pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #define ALLOW_MEGA1280
diff --git a/Marlin/src/pins/mega/pins_LEAPFROG_XEED2015.h b/Marlin/src/pins/mega/pins_LEAPFROG_XEED2015.h
index 4a32472949..7be96c5def 100644
--- a/Marlin/src/pins/mega/pins_LEAPFROG_XEED2015.h
+++ b/Marlin/src/pins/mega/pins_LEAPFROG_XEED2015.h
@@ -23,6 +23,7 @@
 
 /**
  * Leapfrog Xeed Driver board pin assignments
+ * ATmega2560
  *
  * This board is used by other Leapfrog printers in addition to the Xeed,
  * such as the Creatr HS and Bolt. The pin assignments vary wildly between
diff --git a/Marlin/src/pins/mega/pins_MALYAN_M180.h b/Marlin/src/pins/mega/pins_MALYAN_M180.h
index 19095a5379..3ef606de77 100644
--- a/Marlin/src/pins/mega/pins_MALYAN_M180.h
+++ b/Marlin/src/pins/mega/pins_MALYAN_M180.h
@@ -24,6 +24,8 @@
 /**
  * Malyan M180 pin assignments
  * Contributed by Timo Birnschein (timo.birnschein@microforge.de)
+ * @Timo: sind diese Pin Definitionen immernoch korrekt? (Antwort an turningtides@outlook.de bitte)
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_MEGACONTROLLER.h b/Marlin/src/pins/mega/pins_MEGACONTROLLER.h
index 7ebef6e281..f45da25f62 100644
--- a/Marlin/src/pins/mega/pins_MEGACONTROLLER.h
+++ b/Marlin/src/pins/mega/pins_MEGACONTROLLER.h
@@ -23,6 +23,9 @@
 
 /**
  * Mega controller pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Mega%20Controller/Mega_controller.pdf
+ * Origin: https://reprap.org/mediawiki/images/b/ba/Mega_controller.pdf
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/mega/pins_MEGATRONICS.h b/Marlin/src/pins/mega/pins_MEGATRONICS.h
index ac0ba4eea6..a51615e3d9 100644
--- a/Marlin/src/pins/mega/pins_MEGATRONICS.h
+++ b/Marlin/src/pins/mega/pins_MEGATRONICS.h
@@ -23,6 +23,9 @@
 
 /**
  * MegaTronics pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/MegaTronics/Megatronics_1_0_sch.pdf
+ * Origin: https://reprap.org/mediawiki/images/a/a3/Megatronics_1_0_sch.pdf
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_MEGATRONICS_2.h b/Marlin/src/pins/mega/pins_MEGATRONICS_2.h
index e527035910..3f7afe562b 100644
--- a/Marlin/src/pins/mega/pins_MEGATRONICS_2.h
+++ b/Marlin/src/pins/mega/pins_MEGATRONICS_2.h
@@ -23,6 +23,9 @@
 
 /**
  * MegaTronics v2.0 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Megatronics%20v2.0/megatronics%20-%20Project.pdf
+ * Origin: https://reprap.org/wiki/File:Megatronicsv2PDF.zip
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_MEGATRONICS_3.h b/Marlin/src/pins/mega/pins_MEGATRONICS_3.h
index 86aff16f92..b194c31b5d 100644
--- a/Marlin/src/pins/mega/pins_MEGATRONICS_3.h
+++ b/Marlin/src/pins/mega/pins_MEGATRONICS_3.h
@@ -23,6 +23,8 @@
 
 /**
  * MegaTronics v3.0 / v3.1 / v3.2 pin assignments
+ * Schematic Origin: https://github.com/brupje/Megatronics_3/blob/master/Design%20Files/megatronics.sch
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_MIGHTYBOARD_REVE.h b/Marlin/src/pins/mega/pins_MIGHTYBOARD_REVE.h
index 0ef1c1d8ae..56f92f8b25 100644
--- a/Marlin/src/pins/mega/pins_MIGHTYBOARD_REVE.h
+++ b/Marlin/src/pins/mega/pins_MIGHTYBOARD_REVE.h
@@ -23,6 +23,8 @@
 
 /**
  * Mightyboard Rev.E pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Mightyboard%20Rev.E/MakerBot%20MightyBoard%20REVE%20Schematic.pdf
+ * Origin: https://github.com/sciguy14/HelioWatcher/blob/master/HelioWatcher%20Circuit/MakerBot%20MightyBoard%20REVE%20Schematic.pdf
  * also works for Rev D boards. It's all rev E despite what the silk screen says
  */
 
diff --git a/Marlin/src/pins/mega/pins_MINITRONICS.h b/Marlin/src/pins/mega/pins_MINITRONICS.h
index ec712a3b90..ddf6d2047d 100644
--- a/Marlin/src/pins/mega/pins_MINITRONICS.h
+++ b/Marlin/src/pins/mega/pins_MINITRONICS.h
@@ -23,6 +23,11 @@
 
 /**
  * Minitronics v1.0/1.1 pin assignments
+ * Schematic (1.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Minitronics%20v1.0/minitronics%20-%20Project.pdf
+ * Origin (1.0): https://reprap.org/wiki/File:MinitronicsPDF.zip
+ * Datasheet (1.1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Minitronics%20v1.1/datasheet%20minitronics%20v1.1.pdf
+ * Origin (1.1): https://reprapworld.nl/documentation/datasheet%20minitronics%20v1.1.pdf
+ * ATmega1281
  */
 
 /**
diff --git a/Marlin/src/pins/mega/pins_OVERLORD.h b/Marlin/src/pins/mega/pins_OVERLORD.h
index 49accf9f7c..01c02dafe2 100644
--- a/Marlin/src/pins/mega/pins_OVERLORD.h
+++ b/Marlin/src/pins/mega/pins_OVERLORD.h
@@ -23,6 +23,9 @@
 
 /**
  * Dreammaker Overlord v1.1 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Dreammaker%20Overlord%20v1.1/Schematic.pdf
+ * Origin: https://github.com/jdpiercy/Overlord-Pro/blob/master/Motherboard/Schematic.pdf
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/mega/pins_PICA.h b/Marlin/src/pins/mega/pins_PICA.h
index 0e29d8dffe..109859388c 100644
--- a/Marlin/src/pins/mega/pins_PICA.h
+++ b/Marlin/src/pins/mega/pins_PICA.h
@@ -23,6 +23,9 @@
 
 /**
  * Arduino Mega with PICA pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/PICA/pica_schematic.pdf
+ * Origin: https://github.com/mjrice/PICA/blob/master/pica_schematic.pdf
+ * ATmega2560
  *
  * PICA is Power, Interface, and Control Adapter and is open source hardware.
  * See https://github.com/mjrice/PICA for schematics etc.
diff --git a/Marlin/src/pins/mega/pins_PICAOLD.h b/Marlin/src/pins/mega/pins_PICAOLD.h
index e19ea744e5..961462fc52 100644
--- a/Marlin/src/pins/mega/pins_PICAOLD.h
+++ b/Marlin/src/pins/mega/pins_PICAOLD.h
@@ -21,6 +21,10 @@
  */
 #pragma once
 
+// Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/PICAOLD/pica_schematic.pdf
+// Origin: https://github.com/mjrice/PICA/blob/97ab9e7771a8e5eef97788f3adcc17a9fa9de9b9/pica_schematic.pdf
+// ATmega2560
+
 #define HEATER_0_PIN                          9   // E0
 #define HEATER_1_PIN                         10   // E1
 #define FAN_PIN                              11
diff --git a/Marlin/src/pins/mega/pins_PROTONEER_CNC_SHIELD_V3.h b/Marlin/src/pins/mega/pins_PROTONEER_CNC_SHIELD_V3.h
index 88d549c8cb..962fddc192 100644
--- a/Marlin/src/pins/mega/pins_PROTONEER_CNC_SHIELD_V3.h
+++ b/Marlin/src/pins/mega/pins_PROTONEER_CNC_SHIELD_V3.h
@@ -23,6 +23,9 @@
 
 /**
  * Protoneer v3.00 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Protoneer%20CNC%20Shield%20v3.00/Arduino-CNC-Shield-Scematics-V3.XX_.webp
+ * Origin: https://i0.wp.com/blog.protoneer.co.nz/wp-content/uploads/2013/07/Arduino-CNC-Shield-Scematics-V3.XX_.jpg
+ * ATmega2560
  *
  * This CNC shield has an UNO pinout and fits all Arduino-compatibles.
  *
diff --git a/Marlin/src/pins/mega/pins_SILVER_GATE.h b/Marlin/src/pins/mega/pins_SILVER_GATE.h
index 4568ed04e2..6dc0c3963f 100644
--- a/Marlin/src/pins/mega/pins_SILVER_GATE.h
+++ b/Marlin/src/pins/mega/pins_SILVER_GATE.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2561
+
 #if NOT_TARGET(__AVR_ATmega1281__, __AVR_ATmega2561__)
   #error "Oops! Select 'Silvergate' in 'Tools > Board.'"
 #endif
diff --git a/Marlin/src/pins/mega/pins_WANHAO_ONEPLUS.h b/Marlin/src/pins/mega/pins_WANHAO_ONEPLUS.h
index 503dd9ec81..6ab6c4ceb9 100644
--- a/Marlin/src/pins/mega/pins_WANHAO_ONEPLUS.h
+++ b/Marlin/src/pins/mega/pins_WANHAO_ONEPLUS.h
@@ -23,6 +23,7 @@
 
 /**
  * Wanhao 0ne+ pin assignments
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/mega/pins_WEEDO_62A.h b/Marlin/src/pins/mega/pins_WEEDO_62A.h
index 4b3bf6a43b..4165d9e234 100644
--- a/Marlin/src/pins/mega/pins_WEEDO_62A.h
+++ b/Marlin/src/pins/mega/pins_WEEDO_62A.h
@@ -23,6 +23,7 @@
 /**
  * Based on WEEDO 62A pin configuration
  * Copyright (c) 2019 WEEDO3D Perron
+ * ATmega2560
  */
 
 #pragma once
diff --git a/Marlin/src/pins/rambo/pins_EINSY_RAMBO.h b/Marlin/src/pins/rambo/pins_EINSY_RAMBO.h
index de9ecc5b45..c28fbd059c 100644
--- a/Marlin/src/pins/rambo/pins_EINSY_RAMBO.h
+++ b/Marlin/src/pins/rambo/pins_EINSY_RAMBO.h
@@ -23,6 +23,8 @@
 
 /**
  * Einsy-Rambo pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Einsy-Rambo/Schematic%20Prints_Einsy%20Rambo_1.1a.PDF
+ * Origin: https://github.com/ultimachine/Einsy-Rambo/blob/1.1a/board/Project%20Outputs/Schematic%20Prints_Einsy%20Rambo_1.1a.PDF
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/rambo/pins_EINSY_RETRO.h b/Marlin/src/pins/rambo/pins_EINSY_RETRO.h
index 413eb8c98c..dc91c47e9a 100644
--- a/Marlin/src/pins/rambo/pins_EINSY_RETRO.h
+++ b/Marlin/src/pins/rambo/pins_EINSY_RETRO.h
@@ -23,6 +23,10 @@
 
 /**
  * Einsy-Retro pin assignments
+ * Schematic (1.0b): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Einsy-Retro/Schematic%20Prints_EinsyRetro_1.0b.PDF
+ * Origin (1.0b): https://github.com/ultimachine/EinsyRetro/blob/master/board/Project%20Outputs/Schematic%20Prints_EinsyRetro_1.0b.PDF
+ * Schematic (1.0c): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Einsy-Retro/Schematic%20Prints_EinsyRetro_1.0c.PDF
+ * Origin (1.0c): https://github.com/ultimachine/EinsyRetro/blob/master/board/Project%20Outputs/Schematic%20Prints_EinsyRetro_1.0c.PDF
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/rambo/pins_MINIRAMBO.h b/Marlin/src/pins/rambo/pins_MINIRAMBO.h
index 31d44f2b34..353fbd6641 100644
--- a/Marlin/src/pins/rambo/pins_MINIRAMBO.h
+++ b/Marlin/src/pins/rambo/pins_MINIRAMBO.h
@@ -23,6 +23,10 @@
 
 /**
  * Mini-RAMBo pin assignments
+ * Schematic (1.3a): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Mini%20RAMBo/Mini-Rambo.PDF
+ * Origin (1.3a): https://github.com/ultimachine/Mini-Rambo/blob/1.3a/board/Project%20Outputs%20for%20Mini-Rambo/Mini-Rambo.PDF
+ * Schematic (1.0a): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Mini%20RAMBo%201.0a/Mini-Rambo.PDF
+ * Origin (1.0a): https://github.com/ultimachine/Mini-Rambo/blob/v1.1b/board/Project%20Outputs%20for%20Mini-Rambo/Mini-Rambo.PDF
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/rambo/pins_RAMBO.h b/Marlin/src/pins/rambo/pins_RAMBO.h
index cb7a059134..3a26811538 100644
--- a/Marlin/src/pins/rambo/pins_RAMBO.h
+++ b/Marlin/src/pins/rambo/pins_RAMBO.h
@@ -39,6 +39,8 @@
 
 /**
  * Rambo pin assignments
+ * Schematic (1.1b): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMBo/Rambo1-1-schematic.png
+ * Origin (1.1b): https://www.reprap.org/wiki/File:Rambo1-1-schematic.png
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/rambo/pins_SCOOVO_X9H.h b/Marlin/src/pins/rambo/pins_SCOOVO_X9H.h
index 533284a4bf..ca073f5ab9 100644
--- a/Marlin/src/pins/rambo/pins_SCOOVO_X9H.h
+++ b/Marlin/src/pins/rambo/pins_SCOOVO_X9H.h
@@ -25,7 +25,7 @@
  * Rambo pin assignments MODIFIED FOR Scoovo X9H
  ************************************************/
 
-#include "env_target.h"
+#include "env_validate.h"
 
 #define BOARD_INFO_NAME "Scoovo X9H"
 
diff --git a/Marlin/src/pins/ramps/pins_3DRAG.h b/Marlin/src/pins/ramps/pins_3DRAG.h
index 0f90dd5a34..c14284865b 100644
--- a/Marlin/src/pins/ramps/pins_3DRAG.h
+++ b/Marlin/src/pins/ramps/pins_3DRAG.h
@@ -23,6 +23,10 @@
 
 /**
  * 3DRAG (and K8200 / K8400) Arduino Mega with RAMPS v1.4 pin assignments
+ * This may be compatible with the standalone Controller variant.
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/3DRAG%20+%20Controller/Schema_base.jpg
+ * Origin: https://reprap.org/wiki/File:Schema_base.jpg
+ * ATmega2560, ATmega1280
  */
 
 #ifndef BOARD_INFO_NAME
diff --git a/Marlin/src/pins/ramps/pins_AZTEEG_X3.h b/Marlin/src/pins/ramps/pins_AZTEEG_X3.h
index 31adea4270..4d3722655d 100644
--- a/Marlin/src/pins/ramps/pins_AZTEEG_X3.h
+++ b/Marlin/src/pins/ramps/pins_AZTEEG_X3.h
@@ -23,6 +23,9 @@
 
 /**
  * AZTEEG_X3 Arduino Mega with RAMPS v1.4 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/AZTEEG_X3/AZTEEG%20X3%20PUB%20v1.12.pdf
+ * Origin: http://files.panucatt.com/datasheets/azteegx3_designfiles.zip
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_AZTEEG_X3_PRO.h b/Marlin/src/pins/ramps/pins_AZTEEG_X3_PRO.h
index 24266bb9d2..2c666a6f16 100644
--- a/Marlin/src/pins/ramps/pins_AZTEEG_X3_PRO.h
+++ b/Marlin/src/pins/ramps/pins_AZTEEG_X3_PRO.h
@@ -23,6 +23,9 @@
 
 /**
  * AZTEEG_X3_PRO (Arduino Mega) pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/AZTEEG_X3_PRO/AZTEEG%20X3%20PRO%201.0%20PUB.pdf
+ * Origin: http://files.panucatt.com/datasheets/x3pro_sch_v1.0.zip
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_BAM_DICE_DUE.h b/Marlin/src/pins/ramps/pins_BAM_DICE_DUE.h
index fa622ffb15..f3439aa6bb 100644
--- a/Marlin/src/pins/ramps/pins_BAM_DICE_DUE.h
+++ b/Marlin/src/pins/ramps/pins_BAM_DICE_DUE.h
@@ -23,6 +23,9 @@
 
 /**
  * BAM&DICE Due (Arduino Mega) pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/BAM&DICE%20Due/2PRINTBETA-BAM&DICE-DUE-V1.1-sch.pdf
+ * Origin: http://www.2printbeta.de/download/2PRINTBETA-BAM&DICE-DUE-V1.1-sch.pdf
+ * ATmega2560, ATmega1280
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_BIQU_KFB_2.h b/Marlin/src/pins/ramps/pins_BIQU_KFB_2.h
index 58a62fb8bc..6155e9842a 100644
--- a/Marlin/src/pins/ramps/pins_BIQU_KFB_2.h
+++ b/Marlin/src/pins/ramps/pins_BIQU_KFB_2.h
@@ -23,6 +23,7 @@
 
 /**
  * KFB 2.0 – Arduino Mega2560 with RAMPS v1.4 pin assignments
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_BQ_ZUM_MEGA_3D.h b/Marlin/src/pins/ramps/pins_BQ_ZUM_MEGA_3D.h
index 4a54b85ae0..cd3ada25bf 100644
--- a/Marlin/src/pins/ramps/pins_BQ_ZUM_MEGA_3D.h
+++ b/Marlin/src/pins/ramps/pins_BQ_ZUM_MEGA_3D.h
@@ -23,6 +23,9 @@
 
 /**
  * bq ZUM Mega 3D board definition
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/bq%20ZUM%20Mega%203D/Zum%20Mega%203D.PDF
+ * Origin: https://github.com/bq/zum/blob/master/zum-mega3d/Zum%20Mega%203D.PDF
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_COPYMASTER_3D.h b/Marlin/src/pins/ramps/pins_COPYMASTER_3D.h
index 020941027a..1285d0244c 100644
--- a/Marlin/src/pins/ramps/pins_COPYMASTER_3D.h
+++ b/Marlin/src/pins/ramps/pins_COPYMASTER_3D.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2560
+
 #define BOARD_INFO_NAME "Copymaster 3D RAMPS"
 
 #define Z_STEP_PIN                            47
diff --git a/Marlin/src/pins/ramps/pins_DAGOMA_F5.h b/Marlin/src/pins/ramps/pins_DAGOMA_F5.h
index e1bd2ec4ed..9760ccbef5 100644
--- a/Marlin/src/pins/ramps/pins_DAGOMA_F5.h
+++ b/Marlin/src/pins/ramps/pins_DAGOMA_F5.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2560
+
 #if HOTENDS > 2 || E_STEPPERS > 2
   #error "Dagoma3D F5 supports up to 2 hotends / E steppers."
 #endif
diff --git a/Marlin/src/pins/ramps/pins_DUPLICATOR_I3_PLUS.h b/Marlin/src/pins/ramps/pins_DUPLICATOR_I3_PLUS.h
index 1a4b83f02d..7e370a398b 100644
--- a/Marlin/src/pins/ramps/pins_DUPLICATOR_I3_PLUS.h
+++ b/Marlin/src/pins/ramps/pins_DUPLICATOR_I3_PLUS.h
@@ -23,6 +23,7 @@
 
 /**
  * Wanhao Duplicator i3 Plus pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_FELIX2.h b/Marlin/src/pins/ramps/pins_FELIX2.h
index 3e7849d71f..48ef896e96 100644
--- a/Marlin/src/pins/ramps/pins_FELIX2.h
+++ b/Marlin/src/pins/ramps/pins_FELIX2.h
@@ -23,6 +23,7 @@
 
 /**
  * FELIXprinters v2.0/3.0 (RAMPS v1.4) pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR.h b/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR.h
index a6791ff7c8..7bed4c0884 100644
--- a/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR.h
+++ b/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR.h
@@ -23,6 +23,7 @@
 
 /**
  * Formbot Raptor pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR2.h b/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR2.h
index 4fb10bfd35..f0e86ac4a7 100644
--- a/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR2.h
+++ b/Marlin/src/pins/ramps/pins_FORMBOT_RAPTOR2.h
@@ -23,6 +23,7 @@
 
 /**
  * Formbot Raptor 2 pin assignments
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME      "Formbot Raptor2"
diff --git a/Marlin/src/pins/ramps/pins_FORMBOT_TREX2PLUS.h b/Marlin/src/pins/ramps/pins_FORMBOT_TREX2PLUS.h
index 17d3abc71f..a5ca7e8607 100644
--- a/Marlin/src/pins/ramps/pins_FORMBOT_TREX2PLUS.h
+++ b/Marlin/src/pins/ramps/pins_FORMBOT_TREX2PLUS.h
@@ -22,7 +22,8 @@
 #pragma once
 
 /**
- * Formbot pin assignments
+ * Formbot T-Rex 2+ pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_FORMBOT_TREX3.h b/Marlin/src/pins/ramps/pins_FORMBOT_TREX3.h
index e23a63994f..2fa3d60f67 100644
--- a/Marlin/src/pins/ramps/pins_FORMBOT_TREX3.h
+++ b/Marlin/src/pins/ramps/pins_FORMBOT_TREX3.h
@@ -22,7 +22,8 @@
 #pragma once
 
 /**
- * Formbot pin assignments
+ * Formbot T-Rex 3 pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_FYSETC_F6_13.h b/Marlin/src/pins/ramps/pins_FYSETC_F6_13.h
index b8de260909..9f23647c42 100644
--- a/Marlin/src/pins/ramps/pins_FYSETC_F6_13.h
+++ b/Marlin/src/pins/ramps/pins_FYSETC_F6_13.h
@@ -23,6 +23,9 @@
 
 //
 // FYSETC F6 1.3 (and 1.4) pin assignments
+// Schematic (1.3): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/FYSETC%20F6%201.3/F6_V13.pdf
+// Origin: https://github.com/FYSETC/FYSETC-F6/blob/master/Hardware/V1.3/F6_V13.pdf
+// ATmega2560
 //
 
 #if NOT_TARGET(__AVR_ATmega2560__)
diff --git a/Marlin/src/pins/ramps/pins_FYSETC_F6_14.h b/Marlin/src/pins/ramps/pins_FYSETC_F6_14.h
index 1fc24154b7..9604d0ecbf 100644
--- a/Marlin/src/pins/ramps/pins_FYSETC_F6_14.h
+++ b/Marlin/src/pins/ramps/pins_FYSETC_F6_14.h
@@ -23,6 +23,9 @@
 
 //
 // FYSETC F6 v1.4 pin assignments
+// Schematic (1.4): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/FYSETC%20F6%20v1.4/F6%20V1.4%20Sch.pdf
+// Origin (1.4): https://github.com/FYSETC/FYSETC-F6/blob/master/Hardware/V1.4/F6%20V1.4%20Sch.pdf
+// ATmega2560
 //
 
 #define BOARD_INFO_NAME "FYSETC F6 1.4"
diff --git a/Marlin/src/pins/ramps/pins_K8200.h b/Marlin/src/pins/ramps/pins_K8200.h
index 395e1ccca5..d2557b26c3 100644
--- a/Marlin/src/pins/ramps/pins_K8200.h
+++ b/Marlin/src/pins/ramps/pins_K8200.h
@@ -24,6 +24,9 @@
 /**
  * K8200 Arduino Mega with RAMPS v1.3 pin assignments
  * Identical to 3DRAG
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Velleman%20K8200/K8200diagram.jpg
+ * Origin: https://www.velleman.eu/images/tmp/K8200diagram.jpg
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME         "Velleman K8200"
diff --git a/Marlin/src/pins/ramps/pins_K8400.h b/Marlin/src/pins/ramps/pins_K8400.h
index 22ac1be8ab..56ec66191b 100644
--- a/Marlin/src/pins/ramps/pins_K8400.h
+++ b/Marlin/src/pins/ramps/pins_K8400.h
@@ -24,6 +24,9 @@
 /**
  * Velleman K8400 (Vertex)
  * 3DRAG clone
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Velleman%20K8400/k8400-schema-electronique.jpg
+ * Origin: https://filimprimante3d.fr/documents/k8400-schema-electronique.jpg
+ * ATmega2560, ATmega1280
  *
  * K8400 has some minor differences over a normal 3Drag:
  *  - No X/Y max endstops
diff --git a/Marlin/src/pins/ramps/pins_K8600.h b/Marlin/src/pins/ramps/pins_K8600.h
index e4468a6098..3081b04361 100644
--- a/Marlin/src/pins/ramps/pins_K8600.h
+++ b/Marlin/src/pins/ramps/pins_K8600.h
@@ -23,6 +23,7 @@
 
 /**
  * VERTEX NANO Arduino Mega with RAMPS EFB v1.4 pin assignments.
+ * ATmega2560, ATmega1280
  */
 
 #if HAS_MULTI_HOTEND
diff --git a/Marlin/src/pins/ramps/pins_K8800.h b/Marlin/src/pins/ramps/pins_K8800.h
index 17bb59fdc9..a9669764ce 100644
--- a/Marlin/src/pins/ramps/pins_K8800.h
+++ b/Marlin/src/pins/ramps/pins_K8800.h
@@ -23,6 +23,9 @@
 
 /**
  * Velleman K8800 (Vertex)
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Velleman%20K8800/K8800-schematic-V1.4.pdf
+ * Origin: https://www.velleman.eu/downloads/files/vertex-delta/schematics/K8800-schematic-V1.4.pdf
+ * ATmega2560, ATmega1280
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/ramps/pins_LONGER3D_LKx_PRO.h b/Marlin/src/pins/ramps/pins_LONGER3D_LKx_PRO.h
index 51f9cd8038..d9759153c3 100644
--- a/Marlin/src/pins/ramps/pins_LONGER3D_LKx_PRO.h
+++ b/Marlin/src/pins/ramps/pins_LONGER3D_LKx_PRO.h
@@ -23,6 +23,7 @@
 
 /**
  * Longer3D LK1/LK4/LK5 Pro board pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_MAKEBOARD_MINI.h b/Marlin/src/pins/ramps/pins_MAKEBOARD_MINI.h
index a42dba874f..2ab463d681 100644
--- a/Marlin/src/pins/ramps/pins_MAKEBOARD_MINI.h
+++ b/Marlin/src/pins/ramps/pins_MAKEBOARD_MINI.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2560
+
 #define BOARD_INFO_NAME "MAKEboard Mini"
 
 //
diff --git a/Marlin/src/pins/ramps/pins_MKS_BASE_10.h b/Marlin/src/pins/ramps/pins_MKS_BASE_10.h
index 64efa46c05..8d46ac36fa 100644
--- a/Marlin/src/pins/ramps/pins_MKS_BASE_10.h
+++ b/Marlin/src/pins/ramps/pins_MKS_BASE_10.h
@@ -23,6 +23,12 @@
 
 /**
  * MKS BASE 1.0 – Arduino Mega2560 with RAMPS v1.4 pin assignments
+ * Schematics:
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20BASE%201.0/PAGE1.pdf
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20BASE%201.0/PAGE2.pdf
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20BASE%201.0/PAGE3.pdf
+ * Origin: https://reprap.org/wiki/File:MKS_Base_V1.0_source.zip
+ * ATmega2560
  *
  * Rev B - Override pin definitions for CASE_LIGHT and M3/M4/M5 spindle control
  */
diff --git a/Marlin/src/pins/ramps/pins_MKS_BASE_14.h b/Marlin/src/pins/ramps/pins_MKS_BASE_14.h
index 7e2a722cf2..d302def795 100644
--- a/Marlin/src/pins/ramps/pins_MKS_BASE_14.h
+++ b/Marlin/src/pins/ramps/pins_MKS_BASE_14.h
@@ -23,6 +23,7 @@
 
 /**
  * MKS BASE v1.4 with A4982 stepper drivers and digital micro-stepping
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_MKS_BASE_15.h b/Marlin/src/pins/ramps/pins_MKS_BASE_15.h
index 5fedd3f97c..1d93ec5cf9 100644
--- a/Marlin/src/pins/ramps/pins_MKS_BASE_15.h
+++ b/Marlin/src/pins/ramps/pins_MKS_BASE_15.h
@@ -23,6 +23,7 @@
 
 /**
  * MKS BASE v1.5 with A4982 stepper drivers and digital micro-stepping
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_MKS_BASE_16.h b/Marlin/src/pins/ramps/pins_MKS_BASE_16.h
index 63e0b51d3c..765a601fd0 100644
--- a/Marlin/src/pins/ramps/pins_MKS_BASE_16.h
+++ b/Marlin/src/pins/ramps/pins_MKS_BASE_16.h
@@ -23,6 +23,9 @@
 
 /**
  * MKS BASE v1.6 with A4982 stepper drivers and digital micro-stepping
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20BASE%201.6/MKS%20Base%20V1.6_004%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/MKS-BASE/blob/master/hardware/MKS%20Base%20V1.6_004/MKS%20Base%20V1.6_004%20SCH.pdf
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_MKS_BASE_HEROIC.h b/Marlin/src/pins/ramps/pins_MKS_BASE_HEROIC.h
index 973f924e7c..c50f28a407 100644
--- a/Marlin/src/pins/ramps/pins_MKS_BASE_HEROIC.h
+++ b/Marlin/src/pins/ramps/pins_MKS_BASE_HEROIC.h
@@ -23,6 +23,7 @@
 
 /**
  * MKS BASE with Heroic HR4982 stepper drivers
+ * ATmega2560
  */
 
 #include "pins_MKS_BASE_15.h" // ... MKS_BASE_common ... RAMPS
diff --git a/Marlin/src/pins/ramps/pins_MKS_BASE_common.h b/Marlin/src/pins/ramps/pins_MKS_BASE_common.h
index 9047a4bcf0..7608745a4b 100644
--- a/Marlin/src/pins/ramps/pins_MKS_BASE_common.h
+++ b/Marlin/src/pins/ramps/pins_MKS_BASE_common.h
@@ -23,6 +23,7 @@
 
 /**
  * MKS BASE – Arduino Mega2560 with RAMPS pin assignments
+ * ATmega2560
  */
 
 #ifndef BOARD_INFO_NAME
diff --git a/Marlin/src/pins/ramps/pins_MKS_GEN_13.h b/Marlin/src/pins/ramps/pins_MKS_GEN_13.h
index 1e354a10dc..5c13288f85 100644
--- a/Marlin/src/pins/ramps/pins_MKS_GEN_13.h
+++ b/Marlin/src/pins/ramps/pins_MKS_GEN_13.h
@@ -23,6 +23,9 @@
 
 /**
  * Arduino Mega with RAMPS v1.4 adjusted pin assignments
+ * Schematic (1.4): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20GEN%20v1.4/MKS%20GEN%20V1.4_004%20SCH.pdf
+ * Origin (1.4): https://github.com/makerbase-mks/MKS-GEN/blob/master/hardware/MKS%20GEN%20V1.4_004/MKS%20GEN%20V1.4_004%20SCH.pdf
+ * ATmega2560, ATmega1280
  *
  *  MKS GEN v1.3  (Extruder, Fan, Bed)
  *  MKS GEN v1.3  (Extruder, Extruder, Fan, Bed)
diff --git a/Marlin/src/pins/ramps/pins_MKS_GEN_L.h b/Marlin/src/pins/ramps/pins_MKS_GEN_L.h
index dd7f8e5f86..c610fc6206 100644
--- a/Marlin/src/pins/ramps/pins_MKS_GEN_L.h
+++ b/Marlin/src/pins/ramps/pins_MKS_GEN_L.h
@@ -23,6 +23,9 @@
 
 /**
  * MKS GEN L – Arduino Mega2560 with RAMPS v1.4 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20GEN%20L%20v1.0/MKS%20Gen_L%20V1.0_008%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/MKS-GEN_L/blob/master/hardware/MKS%20Gen_L%20V1.0_008/MKS%20Gen_L%20V1.0_008%20SCH.pdf
+ * ATmega2560, ATmega1280
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_MKS_GEN_L_V2.h b/Marlin/src/pins/ramps/pins_MKS_GEN_L_V2.h
index 0378b166a2..d82c4353fd 100644
--- a/Marlin/src/pins/ramps/pins_MKS_GEN_L_V2.h
+++ b/Marlin/src/pins/ramps/pins_MKS_GEN_L_V2.h
@@ -23,6 +23,9 @@
 
 /**
  * MKS GEN L V2 – Arduino Mega2560 with RAMPS v1.4 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20GEN%20L%20V2.0/MKS%20Gen_L%20V2.0_001%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/MKS-GEN_L/blob/master/hardware/MKS%20Gen_L%20V2.0_001/MKS%20Gen_L%20V2.0_001%20SCH.pdf
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_MKS_GEN_L_V21.h b/Marlin/src/pins/ramps/pins_MKS_GEN_L_V21.h
index d508cb453f..c2ab34c825 100644
--- a/Marlin/src/pins/ramps/pins_MKS_GEN_L_V21.h
+++ b/Marlin/src/pins/ramps/pins_MKS_GEN_L_V21.h
@@ -23,6 +23,9 @@
 
 /**
  * MKS GEN L V2 – Arduino Mega2560 with RAMPS v1.4 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/MKS%20GEN%20L%20V2.1/MKS%20GEN_L%20V2.1_001%20SCH.pdf
+ * Origin: https://github.com/makerbase-mks/MKS-GEN_L/blob/master/hardware/MKS%20Gen_L%20V2.1_001/MKS%20GEN_L%20V2.1_001%20SCH.pdf
+ * ATmega2560
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_ORTUR_4.h b/Marlin/src/pins/ramps/pins_ORTUR_4.h
index e47bae1915..7f0fe93084 100644
--- a/Marlin/src/pins/ramps/pins_ORTUR_4.h
+++ b/Marlin/src/pins/ramps/pins_ORTUR_4.h
@@ -23,6 +23,7 @@
 
 /**
  * Ortur 4 Arduino Mega based on RAMPS v1.4 pin assignments
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "Ortur 4.3"
diff --git a/Marlin/src/pins/ramps/pins_PXMALION_CORE_I3.h b/Marlin/src/pins/ramps/pins_PXMALION_CORE_I3.h
index 12c40c7dca..ee0633992e 100644
--- a/Marlin/src/pins/ramps/pins_PXMALION_CORE_I3.h
+++ b/Marlin/src/pins/ramps/pins_PXMALION_CORE_I3.h
@@ -22,6 +22,7 @@
 
 /**
  * Pxmalion Core i3 - https://github.com/Pxmalion
+ * ATmega2560
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/ramps/pins_RAMPS.h b/Marlin/src/pins/ramps/pins_RAMPS.h
index 43780d8d27..08d6475c5e 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega with RAMPS v1.4 (or v1.3) pin assignments
+ * ATmega2560, ATmega1280
  *
  * Applies to the following boards:
  *
diff --git a/Marlin/src/pins/ramps/pins_RAMPS_13.h b/Marlin/src/pins/ramps/pins_RAMPS_13.h
index 6e7c8cbab5..026492e4a8 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS_13.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS_13.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega with RAMPS v1.3 pin assignments
+ * ATmega2560, ATmega1280
  *
  * Applies to the following boards:
  *
diff --git a/Marlin/src/pins/ramps/pins_RAMPS_CREALITY.h b/Marlin/src/pins/ramps/pins_RAMPS_CREALITY.h
index 3d5f5d6f91..5e4366e259 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS_CREALITY.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS_CREALITY.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2560
+
 #if HOTENDS > 2 || E_STEPPERS > 2
   #error "Creality RAMPS supports up to 2 hotends / E steppers."
 #endif
diff --git a/Marlin/src/pins/ramps/pins_RAMPS_ENDER_4.h b/Marlin/src/pins/ramps/pins_RAMPS_ENDER_4.h
index 8f9148b732..3ffa940c48 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS_ENDER_4.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS_ENDER_4.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2560
+
 #if HAS_MULTI_HOTEND || E_STEPPERS > 1
   #error "Ender-4 only supports 1 hotend / E stepper."
 #endif
diff --git a/Marlin/src/pins/ramps/pins_RAMPS_OLD.h b/Marlin/src/pins/ramps/pins_RAMPS_OLD.h
index 9747666235..526045c155 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS_OLD.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS_OLD.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega with RAMPS v1.0, v1.1, v1.2 pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/ramps/pins_RAMPS_PLUS.h b/Marlin/src/pins/ramps/pins_RAMPS_PLUS.h
index 8ccb14c866..f93c6919d9 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS_PLUS.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS_PLUS.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega with RAMPS v1.4Plus, also known as 3DYMY version, pin assignments
+ * ATmega2560, ATmega1280
  *
  * Applies to the following boards:
  *
diff --git a/Marlin/src/pins/ramps/pins_RAMPS_S_12.h b/Marlin/src/pins/ramps/pins_RAMPS_S_12.h
index 8d6a1d337e..e74480a0d4 100644
--- a/Marlin/src/pins/ramps/pins_RAMPS_S_12.h
+++ b/Marlin/src/pins/ramps/pins_RAMPS_S_12.h
@@ -24,6 +24,7 @@
 /**
  * Arduino Mega with RAMPS-S v1.2 by Sakul.cz pin assignments
  * Written by Michal Rábek <rabek33@gmail.com>
+ * ATmega2560
  *
  * Applies to the following boards:
  *
diff --git a/Marlin/src/pins/ramps/pins_RIGIDBOARD.h b/Marlin/src/pins/ramps/pins_RIGIDBOARD.h
index 273e0274a8..d1824d3813 100644
--- a/Marlin/src/pins/ramps/pins_RIGIDBOARD.h
+++ b/Marlin/src/pins/ramps/pins_RIGIDBOARD.h
@@ -23,6 +23,7 @@
 
 /**
  * RIGIDBOARD Arduino Mega with RAMPS v1.4 pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #ifndef BOARD_INFO_NAME
diff --git a/Marlin/src/pins/ramps/pins_RIGIDBOARD_V2.h b/Marlin/src/pins/ramps/pins_RIGIDBOARD_V2.h
index 8242f1a772..dc27378a15 100644
--- a/Marlin/src/pins/ramps/pins_RIGIDBOARD_V2.h
+++ b/Marlin/src/pins/ramps/pins_RIGIDBOARD_V2.h
@@ -23,6 +23,7 @@
 
 /**
  * RIGIDBOARD V2 Arduino Mega with RAMPS v1.4 pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #define BOARD_INFO_NAME "RigidBoard V2"
diff --git a/Marlin/src/pins/ramps/pins_RL200.h b/Marlin/src/pins/ramps/pins_RL200.h
index 00fb39a439..219a3a525d 100644
--- a/Marlin/src/pins/ramps/pins_RL200.h
+++ b/Marlin/src/pins/ramps/pins_RL200.h
@@ -24,6 +24,7 @@
 /**
  * Rapide Lite 200 v1 (RUMBA clone) pin assignments. Has slightly different assignment for
  * extruder motors due to dual Z motors. Pinout therefore based on pins_RUMBA.h.
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "RL200"
diff --git a/Marlin/src/pins/ramps/pins_RUMBA.h b/Marlin/src/pins/ramps/pins_RUMBA.h
index eb049c48dd..6b1f4c5691 100644
--- a/Marlin/src/pins/ramps/pins_RUMBA.h
+++ b/Marlin/src/pins/ramps/pins_RUMBA.h
@@ -23,6 +23,9 @@
 
 /**
  * RUMBA pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/RUMBA/RRD-RUMBA_SCHEMATICS.png
+ * Origin: https://reprap.org/wiki/File:RRD-RUMBA_SCHEMATICS.png
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_RUMBA_RAISE3D.h b/Marlin/src/pins/ramps/pins_RUMBA_RAISE3D.h
index 39942613ff..57ee32ab29 100644
--- a/Marlin/src/pins/ramps/pins_RUMBA_RAISE3D.h
+++ b/Marlin/src/pins/ramps/pins_RUMBA_RAISE3D.h
@@ -21,6 +21,8 @@
  */
 #pragma once
 
+// ATmega2560
+
 #define BOARD_INFO_NAME      "Raise3D Rumba"
 #define DEFAULT_MACHINE_NAME "Raise3D N Series"
 
diff --git a/Marlin/src/pins/ramps/pins_SAINSMART_2IN1.h b/Marlin/src/pins/ramps/pins_SAINSMART_2IN1.h
index d25029a7a3..6354cc7618 100644
--- a/Marlin/src/pins/ramps/pins_SAINSMART_2IN1.h
+++ b/Marlin/src/pins/ramps/pins_SAINSMART_2IN1.h
@@ -23,13 +23,14 @@
 
 /**
  * Sainsmart 2-in-1 pin assignments
+ * ATmega2560, ATmega1280
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
   #error "Sainsmart 2-in-1 supports up to 2 hotends / E steppers."
 #endif
 
-#define BOARD_INFO_NAME "Sainsmart"
+#define BOARD_INFO_NAME "Sainsmart 2-in-1"
 
 //
 // Heaters / Fans
diff --git a/Marlin/src/pins/ramps/pins_TANGO.h b/Marlin/src/pins/ramps/pins_TANGO.h
index 451d2f874d..936751e9eb 100644
--- a/Marlin/src/pins/ramps/pins_TANGO.h
+++ b/Marlin/src/pins/ramps/pins_TANGO.h
@@ -23,6 +23,9 @@
 
 /**
  * BIQU Tango pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/BIQU%20Tango/schematic.png
+ * Origin: https://github.com/bigtreetech/Tango-3D-Printer-Motherboard/blob/master/Schematic/Tango%20V1.0.SchDoc
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "Tango"
diff --git a/Marlin/src/pins/ramps/pins_TENLOG_D3_HERO.h b/Marlin/src/pins/ramps/pins_TENLOG_D3_HERO.h
index b11487b21d..dd6fb2fa70 100644
--- a/Marlin/src/pins/ramps/pins_TENLOG_D3_HERO.h
+++ b/Marlin/src/pins/ramps/pins_TENLOG_D3_HERO.h
@@ -22,7 +22,8 @@
 #pragma once
 
 /**
- * Tenlog pin assignments
+ * Tenlog D3 Hero pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_TENLOG_MB1_V23.h b/Marlin/src/pins/ramps/pins_TENLOG_MB1_V23.h
index b3f7d5f216..780ab8daa4 100644
--- a/Marlin/src/pins/ramps/pins_TENLOG_MB1_V23.h
+++ b/Marlin/src/pins/ramps/pins_TENLOG_MB1_V23.h
@@ -22,7 +22,8 @@
 #pragma once
 
 /**
- * Tenlog pin assignments
+ * Tenlog MB1 V2.3 pin assignments
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_TRIGORILLA_13.h b/Marlin/src/pins/ramps/pins_TRIGORILLA_13.h
index 6e51a8e974..83dac111cb 100644
--- a/Marlin/src/pins/ramps/pins_TRIGORILLA_13.h
+++ b/Marlin/src/pins/ramps/pins_TRIGORILLA_13.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega with RAMPS v1.3 for Anycubic
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "Anycubic RAMPS 1.3"
diff --git a/Marlin/src/pins/ramps/pins_TRIGORILLA_14.h b/Marlin/src/pins/ramps/pins_TRIGORILLA_14.h
index 96c3fced4c..f9856e04f5 100644
--- a/Marlin/src/pins/ramps/pins_TRIGORILLA_14.h
+++ b/Marlin/src/pins/ramps/pins_TRIGORILLA_14.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega with RAMPS v1.4 for Anycubic
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "Anycubic RAMPS 1.4"
diff --git a/Marlin/src/pins/ramps/pins_TRONXY_V3_1_0.h b/Marlin/src/pins/ramps/pins_TRONXY_V3_1_0.h
index 04c6af67b0..0104dadf7f 100644
--- a/Marlin/src/pins/ramps/pins_TRONXY_V3_1_0.h
+++ b/Marlin/src/pins/ramps/pins_TRONXY_V3_1_0.h
@@ -23,6 +23,7 @@
 
 /**
  * Arduino Mega for Tronxy X5S-2E, etc.
+ * ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/ramps/pins_TT_OSCAR.h b/Marlin/src/pins/ramps/pins_TT_OSCAR.h
index ecc708b395..c0247c7b47 100644
--- a/Marlin/src/pins/ramps/pins_TT_OSCAR.h
+++ b/Marlin/src/pins/ramps/pins_TT_OSCAR.h
@@ -21,10 +21,12 @@
  */
 #pragma once
 
+// ATmega2560
+
 #include "env_validate.h"
 
 #if HOTENDS > 5 || E_STEPPERS > 5
-  #error "TTOSCAR supports up to 5 hotends / E steppers."
+  #error "TT OSCAR supports up to 5 hotends / E steppers."
 #endif
 
 #define BOARD_INFO_NAME      "TT OSCAR"
diff --git a/Marlin/src/pins/ramps/pins_ULTIMAIN_2.h b/Marlin/src/pins/ramps/pins_ULTIMAIN_2.h
index 0b15cd35ad..4ee0a6950d 100644
--- a/Marlin/src/pins/ramps/pins_ULTIMAIN_2.h
+++ b/Marlin/src/pins/ramps/pins_ULTIMAIN_2.h
@@ -23,6 +23,25 @@
 
 /**
  * Ultiboard v2.0 pin assignments
+ * Schematics (2.1.4):
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%202.1.4/schema1.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%202.1.4/schema2.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%202.1.4/schema3.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%202.1.4/schema4.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%202.1.4/schema5.png
+ * Origins (2.1.4):
+ * - https://github.com/Ultimaker/Ultimaker2/blob/master/1546%20ultimainboard%20V2.1.4/schema1.SchDoc
+ * - https://github.com/Ultimaker/Ultimaker2/blob/master/1546%20ultimainboard%20V2.1.4/schema2.SchDoc
+ * - https://github.com/Ultimaker/Ultimaker2/blob/master/1546%20ultimainboard%20V2.1.4/schema3.SchDoc
+ * - https://github.com/Ultimaker/Ultimaker2/blob/master/1546%20ultimainboard%20V2.1.4/schema4.SchDoc
+ * - https://github.com/Ultimaker/Ultimaker2/blob/master/1546%20ultimainboard%20V2.1.4/schema5.SchDoc
+ * Schematics (Original+):
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%20Original+/Ultimainboard%20rev.%202.1.1%20altium/schema1.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%20Original+/Ultimainboard%20rev.%202.1.1%20altium/schema2.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%20Original+/Ultimainboard%20rev.%202.1.1%20altium/schema3.png
+ * - https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%20Original+/Ultimainboard%20rev.%202.1.1%20altium/schema4.png
+ * Origin (Original+): https://github.com/Ultimaker/Ultimaker-Original-Plus/blob/master/1091_Main_board_v2.1.1_(x1)/Ultimainboard%20rev.%202.1.1%20altium.zip
+ * ATmega2560
  */
 
 /**
diff --git a/Marlin/src/pins/ramps/pins_ULTIMAKER.h b/Marlin/src/pins/ramps/pins_ULTIMAKER.h
index 0bc04d962a..e3e91428df 100644
--- a/Marlin/src/pins/ramps/pins_ULTIMAKER.h
+++ b/Marlin/src/pins/ramps/pins_ULTIMAKER.h
@@ -23,6 +23,7 @@
 
 /**
  * Ultimaker pin assignments
+ * ATmega2560, ATmega1280
  */
 
 /**
diff --git a/Marlin/src/pins/ramps/pins_ULTIMAKER_OLD.h b/Marlin/src/pins/ramps/pins_ULTIMAKER_OLD.h
index 146c519ff9..25cc278ada 100644
--- a/Marlin/src/pins/ramps/pins_ULTIMAKER_OLD.h
+++ b/Marlin/src/pins/ramps/pins_ULTIMAKER_OLD.h
@@ -23,6 +23,9 @@
 
 /**
  * Ultimaker pin assignments (Old electronics)
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%201.0/ultipanel%20rev1.1.sch.pdf
+ * Origin: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/Ultimaker%201.0/ultipanel%20rev1.1.sch.pdf
+ * ATmega2560, ATmega1280
  */
 
 /**
diff --git a/Marlin/src/pins/ramps/pins_VORON.h b/Marlin/src/pins/ramps/pins_VORON.h
index 9390381010..f56b0cb8fc 100644
--- a/Marlin/src/pins/ramps/pins_VORON.h
+++ b/Marlin/src/pins/ramps/pins_VORON.h
@@ -24,6 +24,7 @@
 /**
  * VORON Design v2 pin assignments
  * See https://github.com/mzbotreprap/VORON/blob/master/Firmware/Marlin/pins_RAMPS_VORON.h
+ * ATmega2560
  */
 
 #define BOARD_INFO_NAME "VORON Design v2"
diff --git a/Marlin/src/pins/ramps/pins_ZRIB_V20.h b/Marlin/src/pins/ramps/pins_ZRIB_V20.h
index 3e236e36ba..127fffa794 100644
--- a/Marlin/src/pins/ramps/pins_ZRIB_V20.h
+++ b/Marlin/src/pins/ramps/pins_ZRIB_V20.h
@@ -22,8 +22,13 @@
 #pragma once
 
 /**
- * ZRIB V2.0 & V3.0 pin assignments
+ * ZONESTAR ZRIB V2.0 & V3.0 pin assignments
  * V2 and V3 Boards only differ in USB controller, nothing affecting the pins.
+ * Schematic (2.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/ZONESTAR%20ZRIB%20V2.0/ZRIB_V2_Schematic.pdf
+ * Origin (2.0): https://github.com/ZONESTAR3D/Control-Board/blob/main/8bit/ZRIB/ZRIB_V2/ZRIB_V2_Schematic.pdf
+ * Schematic (3.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/ZONESTAR%20ZRIB%20V3.0/ZRIB_V3_Schematic.pdf
+ * Origin (3.0): https://github.com/ZONESTAR3D/Control-Board/blob/main/8bit/ZRIB/ZRIB_V3/ZRIB_V3_Schematic.pdf
+ * ATmega2560, ATmega1280
  */
 
 #ifndef FILWIDTH_PIN
diff --git a/Marlin/src/pins/ramps/pins_ZRIB_V52.h b/Marlin/src/pins/ramps/pins_ZRIB_V52.h
index 44e0beaa9f..34eee07c95 100644
--- a/Marlin/src/pins/ramps/pins_ZRIB_V52.h
+++ b/Marlin/src/pins/ramps/pins_ZRIB_V52.h
@@ -22,7 +22,10 @@
 #pragma once
 
 /**
- * ZRIB V5.2 Based on MKS BASE v1.4 with A4982 stepper drivers and digital micro-stepping
+ * ZONESTAR ZRIB V5.2 Based on MKS BASE v1.4 with A4982 stepper drivers and digital micro-stepping
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/RAMPS/ZONESTAR%20ZRIB%20V5.2/ZRIB_V52_Schematic.pdf
+ * Origin: https://github.com/ZONESTAR3D/Control-Board/blob/main/8bit/ZRIB/ZRIB_V5/ZRIB_V52_Schematic.pdf
+ * ATmega2560, ATmega1280
  */
 
 #if HOTENDS > 2 || E_STEPPERS > 2
diff --git a/Marlin/src/pins/ramps/pins_ZRIB_V53.h b/Marlin/src/pins/ramps/pins_ZRIB_V53.h
index 7a5cf14791..050516791e 100644
--- a/Marlin/src/pins/ramps/pins_ZRIB_V53.h
+++ b/Marlin/src/pins/ramps/pins_ZRIB_V53.h
@@ -22,7 +22,8 @@
 #pragma once
 
 /**
- * ZRIB V5.3 Based on MKS BASE v1.4 with A4982 stepper drivers and digital micro-stepping
+ * ZONESTAR ZRIB V5.3 Based on MKS BASE v1.4 with A4982 stepper drivers and digital micro-stepping
+ * ATmega2560, ATmega1280
  */
 
 #include "env_validate.h"
diff --git a/Marlin/src/pins/ramps/pins_Z_BOLT_X_SERIES.h b/Marlin/src/pins/ramps/pins_Z_BOLT_X_SERIES.h
index ad7b859a0c..1c67903a21 100644
--- a/Marlin/src/pins/ramps/pins_Z_BOLT_X_SERIES.h
+++ b/Marlin/src/pins/ramps/pins_Z_BOLT_X_SERIES.h
@@ -23,6 +23,7 @@
 
 /**
  *  Z-Bolt X Series board – based on Arduino Mega2560
+ *  ATmega2560
  */
 
 #define REQUIRE_MEGA2560
diff --git a/Marlin/src/pins/sanguino/pins_ANET_10.h b/Marlin/src/pins/sanguino/pins_ANET_10.h
index bd69e167dc..f6816bfb95 100644
--- a/Marlin/src/pins/sanguino/pins_ANET_10.h
+++ b/Marlin/src/pins/sanguino/pins_ANET_10.h
@@ -23,6 +23,8 @@
 
 /**
  * Anet V1.0 board pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Anet%20V1.0/ANET3D_Board_Schematic.pdf
+ * Origin: https://github.com/ralf-e/ANET-3D-Board-V1.0/blob/master/ANET3D_Board_Schematic.pdf
  */
 
 /**
diff --git a/Marlin/src/pins/sanguino/pins_AZTEEG_X1.h b/Marlin/src/pins/sanguino/pins_AZTEEG_X1.h
index 4c721da000..76d53c6021 100644
--- a/Marlin/src/pins/sanguino/pins_AZTEEG_X1.h
+++ b/Marlin/src/pins/sanguino/pins_AZTEEG_X1.h
@@ -23,6 +23,8 @@
 
 /**
  * Azteeg X1 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Azteeg%20X1/Azteeg_X1_schematics.pdf
+ * Origin: https://reprap.org/mediawiki/images/0/07/Azteeg_X1_schematics.pdf
  */
 
 #define BOARD_INFO_NAME "Azteeg X1"
diff --git a/Marlin/src/pins/sanguino/pins_GEN3_MONOLITHIC.h b/Marlin/src/pins/sanguino/pins_GEN3_MONOLITHIC.h
index 1343739a11..a5afc30187 100644
--- a/Marlin/src/pins/sanguino/pins_GEN3_MONOLITHIC.h
+++ b/Marlin/src/pins/sanguino/pins_GEN3_MONOLITHIC.h
@@ -23,6 +23,7 @@
 
 /**
  * Gen3 Monolithic Electronics pin assignments
+ * https://reprap.org/wiki/Generation_3_Electronics
  */
 
 /**
diff --git a/Marlin/src/pins/sanguino/pins_GEN6.h b/Marlin/src/pins/sanguino/pins_GEN6.h
index 51e8200b95..75138845f4 100644
--- a/Marlin/src/pins/sanguino/pins_GEN6.h
+++ b/Marlin/src/pins/sanguino/pins_GEN6.h
@@ -23,6 +23,8 @@
 
 /**
  * Gen6 pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen6/GEN6_Mendel_Circuit.pdf
+ * Origin: https://reprap.org/mediawiki/images/0/0f/GEN6_Mendel_Circuit.pdf
  */
 
  /**
diff --git a/Marlin/src/pins/sanguino/pins_GEN7_12.h b/Marlin/src/pins/sanguino/pins_GEN7_12.h
index 0834da78c4..ade59fd807 100644
--- a/Marlin/src/pins/sanguino/pins_GEN7_12.h
+++ b/Marlin/src/pins/sanguino/pins_GEN7_12.h
@@ -23,6 +23,14 @@
 
 /**
  * Gen7 v1.1, v1.2, v1.3 pin assignments
+ * Schematic (1.1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen7%20v1.1/Gen7Board%20Schematic.pdf
+ * Origin (1.1): https://github.com/Traumflug/Generation_7_Electronics/blob/release-1.1/release%20documents/Gen7Board%20Schematic.pdf
+ * Schematic (1.2): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen7%20v1.2/Gen7Board%20Schematic.pdf
+ * Origin (1.2): https://github.com/Traumflug/Generation_7_Electronics/blob/release-1.2/release%20documents/Gen7Board%20Schematic.pdf
+ * Schematic (1.3): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen7%20v1.3/Gen7Board%20Schematic.pdf
+ * Origin (1.3): https://github.com/Traumflug/Generation_7_Electronics/blob/release-1.3/release%20documents/Gen7Board%20Schematic.pdf
+ * Schematic (1.3.1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen7%20v1.3.1/Gen7Board%20Schematic.pdf
+ * Origin (1.3.1): https://github.com/Traumflug/Generation_7_Electronics/blob/release-1.3.1/release%20documents/Gen7Board%20Schematic.pdf
  */
 
  /**
@@ -54,7 +62,7 @@
 #include "env_validate.h"
 
 #ifndef BOARD_INFO_NAME
-  #define BOARD_INFO_NAME "Gen7 v1.1 / 1.2"
+  #define BOARD_INFO_NAME "Gen7 v1.1 - v1.3"
 #endif
 
 #ifndef GEN7_VERSION
diff --git a/Marlin/src/pins/sanguino/pins_GEN7_14.h b/Marlin/src/pins/sanguino/pins_GEN7_14.h
index 97bfdd28a7..698bd06606 100644
--- a/Marlin/src/pins/sanguino/pins_GEN7_14.h
+++ b/Marlin/src/pins/sanguino/pins_GEN7_14.h
@@ -23,6 +23,10 @@
 
 /**
  * Gen7 v1.4 pin assignments
+ * Schematic (1.4): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen7%20v1.4/Gen7Board%201.4%20Schematic.pdf
+ * Origin (1.4): https://github.com/Traumflug/Generation_7_Electronics/blob/Gen7Board-1.4/release%20documents/Gen7Board%201.4%20Schematic.pdf
+ * Schematic (1.4.1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Gen7%20v1.4.1/Gen7Board%201.4.1%20Schematic.pdf
+ * Origin (1.4.1): https://github.com/Traumflug/Generation_7_Electronics/blob/Gen7Board-1.4.1/release%20documents/Gen7Board%201.4.1%20Schematic.pdf
  */
 
 /**
diff --git a/Marlin/src/pins/sanguino/pins_MELZI.h b/Marlin/src/pins/sanguino/pins_MELZI.h
index d6f9288e8c..be1b7934c8 100644
--- a/Marlin/src/pins/sanguino/pins_MELZI.h
+++ b/Marlin/src/pins/sanguino/pins_MELZI.h
@@ -23,6 +23,8 @@
 
 /**
  * Melzi pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Melzi/schematic.pdf
+ * Origin: https://github.com/mosfet/melzi/blob/master/melzi.sch
  */
 
 #ifndef BOARD_INFO_NAME
diff --git a/Marlin/src/pins/sanguino/pins_MELZI_CREALITY.h b/Marlin/src/pins/sanguino/pins_MELZI_CREALITY.h
index acaf06ed9d..a61692c9f1 100644
--- a/Marlin/src/pins/sanguino/pins_MELZI_CREALITY.h
+++ b/Marlin/src/pins/sanguino/pins_MELZI_CREALITY.h
@@ -23,6 +23,9 @@
 
 /**
  * Melzi (Creality) pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Melzi%20(Creality)/CR-10%20Schematic.pdf
+ * Origin: https://github.com/Creality3DPrinting/CR10-Melzi-1.1.2/blob/master/Circuit%20diagram/Motherboard/CR-10%20Schematic.pdf
+ * ATmega1284P
  *
  * The Creality board needs a bootloader installed before Marlin can be uploaded.
  * If you don't have a chip programmer you can use a spare Arduino plus a few
diff --git a/Marlin/src/pins/sanguino/pins_MELZI_MALYAN.h b/Marlin/src/pins/sanguino/pins_MELZI_MALYAN.h
index d6f36cc6f5..00c9db6f81 100644
--- a/Marlin/src/pins/sanguino/pins_MELZI_MALYAN.h
+++ b/Marlin/src/pins/sanguino/pins_MELZI_MALYAN.h
@@ -23,6 +23,7 @@
 
 /**
  * Melzi (Malyan M150) pin assignments
+ * ATmega644P, ATmega1284P
  */
 
 #define BOARD_INFO_NAME "Melzi (Malyan)"
diff --git a/Marlin/src/pins/sanguino/pins_MELZI_TRONXY.h b/Marlin/src/pins/sanguino/pins_MELZI_TRONXY.h
index aecad10dab..da010ab1a6 100644
--- a/Marlin/src/pins/sanguino/pins_MELZI_TRONXY.h
+++ b/Marlin/src/pins/sanguino/pins_MELZI_TRONXY.h
@@ -23,6 +23,7 @@
 
 /**
  * Melzi pin assignments
+ * ATmega644P, ATmega1284P
  */
 
 #define BOARD_INFO_NAME "Melzi (Tronxy)"
diff --git a/Marlin/src/pins/sanguino/pins_MELZI_V2.h b/Marlin/src/pins/sanguino/pins_MELZI_V2.h
index e49eb57b11..2cd949e095 100644
--- a/Marlin/src/pins/sanguino/pins_MELZI_V2.h
+++ b/Marlin/src/pins/sanguino/pins_MELZI_V2.h
@@ -23,6 +23,8 @@
 
 /**
  * Melzi V2.0 as found at https://www.reprap.org/wiki/Melzi
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Melzi%20V2/Melzi-circuit.png
+ * Origin: https://www.reprap.org/mediawiki/images/7/7d/Melzi-circuit.png
  */
 
 #define BOARD_INFO_NAME "Melzi V2"
diff --git a/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_11.h b/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_11.h
index 6444e2e040..a8475fb326 100644
--- a/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_11.h
+++ b/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_11.h
@@ -23,6 +23,16 @@
 
 /**
  * Sanguinololu board pin assignments
+ * Schematic (0.1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v0.1/schematic.png
+ * Origin (0.1): https://github.com/mosfet/Sanguinololu/blob/master/rev0.1/sanguinololu.sch
+ * Schematic (0.6): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v0.6/schematic.jpg
+ * Origin (0.6): https://github.com/mosfet/Sanguinololu/blob/master/rev0.6/images/schematic.jpg
+ * Schematic (0.7): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v0.7/schematic.jpg
+ * Origin (0.7): https://github.com/mosfet/Sanguinololu/blob/master/rev0.7/images/schematic.jpg
+ * Schematic (1.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v1.0/Sanguinololu-schematic.jpg
+ * Origin (1.0): https://reprap.org/wiki/File:Sanguinololu-schematic.jpg
+ * Schematic (1.1): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v1.1/schematic.png
+ * Origin (1.1): https://github.com/mosfet/Sanguinololu/blob/master/rev1.1/sanguinololu.sch
  */
 
 /**
diff --git a/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_12.h b/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_12.h
index ec7621e28f..2209569261 100644
--- a/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_12.h
+++ b/Marlin/src/pins/sanguino/pins_SANGUINOLOLU_12.h
@@ -23,6 +23,12 @@
 
 /**
  * Sanguinololu V1.2 pin assignments
+ * Schematic (1.2): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v1.2/schematic.png
+ * Origin (1.2): https://github.com/mosfet/Sanguinololu/blob/master/rev1.2/sanguinololu.sch
+ * Schematic (1.3): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v1.3/schematic.png
+ * Origin (1.3): https://github.com/mosfet/Sanguinololu/blob/master/rev1.3/sanguinololu.sch
+ * Schematic (1.3a): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Sanguinololu%20v1.3a/schematic.png
+ * Origin (1.3a): https://github.com/mosfet/Sanguinololu/blob/master/rev1.3a/sanguinololu.sch
  *
  * Applies to the following boards:
  *
diff --git a/Marlin/src/pins/sanguino/pins_STB_11.h b/Marlin/src/pins/sanguino/pins_STB_11.h
index ad0919e99e..1bda25b3d4 100644
--- a/Marlin/src/pins/sanguino/pins_STB_11.h
+++ b/Marlin/src/pins/sanguino/pins_STB_11.h
@@ -22,7 +22,8 @@
 #pragma once
 
 /**
- * STB V1.1 pin assignments
+ * STB Electronics V1.1 pin assignments
+ * https://www.reprap.org/wiki/STB_Electronics
  */
 
 #define BOARD_INFO_NAME "STB V1.1"
diff --git a/Marlin/src/pins/sanguino/pins_ZMIB_V2.h b/Marlin/src/pins/sanguino/pins_ZMIB_V2.h
index aa3ce556d1..bd9230c32a 100644
--- a/Marlin/src/pins/sanguino/pins_ZMIB_V2.h
+++ b/Marlin/src/pins/sanguino/pins_ZMIB_V2.h
@@ -31,6 +31,8 @@
 
 /**
  * ZMIB pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/ZONESTAR%20ZMIB%20V2/ZMIB_V2_Schmatic.pdf
+ * Origin: https://github.com/ZONESTAR3D/Control-Board/blob/main/8bit/ZMIB/ZMIB%20V2/ZMIB_V2_Schmatic.pdf
  *
  * The ZMIB board needs a bootloader installed before Marlin can be uploaded.
  * If you don't have a chip programmer you can use a spare Arduino plus a few
diff --git a/Marlin/src/pins/teensy2/pins_5DPRINT.h b/Marlin/src/pins/teensy2/pins_5DPRINT.h
index 6e1f9c0217..9eb1da36f4 100644
--- a/Marlin/src/pins/teensy2/pins_5DPRINT.h
+++ b/Marlin/src/pins/teensy2/pins_5DPRINT.h
@@ -64,6 +64,8 @@
 
 /**
  * 5DPrint D8 Driver board pin assignments
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/5DPrint%20D8/5DPD8_v1.0_OS_schematics.PDF
+ * Origin: https://bitbucket.org/makible/5dprint-d8-controller-board/src/master/5DPD8_v1.0_OS_schematics.PDF
  *
  * https://bitbucket.org/makible/5dprint-d8-controller-board
  */
diff --git a/Marlin/src/pins/teensy2/pins_BRAINWAVE.h b/Marlin/src/pins/teensy2/pins_BRAINWAVE.h
index cdcc249c00..bbda3730ee 100644
--- a/Marlin/src/pins/teensy2/pins_BRAINWAVE.h
+++ b/Marlin/src/pins/teensy2/pins_BRAINWAVE.h
@@ -23,9 +23,13 @@
 
 /**
  * Brainwave 1.0 pin assignments (AT90USB646)
+ * https://www.reprap.org/wiki/Brainwave
  *
  * Requires hardware bundle for Arduino:
  * https://github.com/unrepentantgeek/brainwave-arduino
+ *
+ * Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Brainwave/schematic.pdf
+ * Origin: https://github.com/unrepentantgeek/Brainwave/blob/master/brainwave/brainwave.sch
  */
 
 /**
diff --git a/Marlin/src/pins/teensy2/pins_BRAINWAVE_PRO.h b/Marlin/src/pins/teensy2/pins_BRAINWAVE_PRO.h
index 319130ef96..969ec84558 100644
--- a/Marlin/src/pins/teensy2/pins_BRAINWAVE_PRO.h
+++ b/Marlin/src/pins/teensy2/pins_BRAINWAVE_PRO.h
@@ -26,6 +26,8 @@
  *
  * Requires hardware bundle for Arduino:
  * https://github.com/unrepentantgeek/brainwave-arduino
+ *
+ * Not to be confused with the regular Brainwave controller (https://www.reprap.org/wiki/Brainwave)
  */
 
 /**
diff --git a/Marlin/src/pins/teensy2/pins_PRINTRBOARD.h b/Marlin/src/pins/teensy2/pins_PRINTRBOARD.h
index ddf0d53ea6..1fb7387d16 100644
--- a/Marlin/src/pins/teensy2/pins_PRINTRBOARD.h
+++ b/Marlin/src/pins/teensy2/pins_PRINTRBOARD.h
@@ -25,6 +25,15 @@
  *  Rev B  2 JUN 2017
  *
  *  Converted to Arduino pin numbering
+ *
+ *  Schematic (RevA): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.A/schematic.png
+ *  Origin (RevA): https://raw.githubusercontent.com/lwalkera/printrboard/revA/Printrboard.sch
+ *  Schematic (RevB): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.B/schematic.png
+ *  Origin (RevB): https://raw.githubusercontent.com/lwalkera/printrboard/revB/Printrboard.sch
+ *  Schematic (RevC): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.C/schematic.png
+ *  Origin (RevC): https://raw.githubusercontent.com/lwalkera/printrboard/revC/Printrboard.sch
+ *  Schematic (RevD): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.D/schematic.png
+ *  Origin (RevD): https://raw.githubusercontent.com/lwalkera/printrboard/RevD/Printrboard.sch
  */
 
 /**
diff --git a/Marlin/src/pins/teensy2/pins_PRINTRBOARD_REVF.h b/Marlin/src/pins/teensy2/pins_PRINTRBOARD_REVF.h
index 1867398087..5ce106b485 100644
--- a/Marlin/src/pins/teensy2/pins_PRINTRBOARD_REVF.h
+++ b/Marlin/src/pins/teensy2/pins_PRINTRBOARD_REVF.h
@@ -25,6 +25,19 @@
  *  Rev B  2 JUN 2017
  *
  *  Converted to Arduino pin numbering
+ *
+ *  Schematic (RevF): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.F/schematic.png
+ *  Origin (RevF): https://github.com/lwalkera/printrboard/raw/revF/Printrboard.sch
+ *  Schematic (RevF2): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.F2/schematic.png
+ *  Origin (RevF2): https://raw.githubusercontent.com/lwalkera/printrboard/revF2/Printrboard.sch
+ *  Schematic (RevF3): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.F3/schematic.png
+ *  Origin (RevF3): https://raw.githubusercontent.com/lwalkera/printrboard/revF3/Printrboard.sch
+ *  Schematic (RevF4): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.F4/schematic.png
+ *  Origin (RevF4): https://raw.githubusercontent.com/lwalkera/printrboard/revF4/Printrboard.sch
+ *  Schematic (RevF5): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.F5/schematic.png
+ *  Origin (RevF5): https://raw.githubusercontent.com/lwalkera/printrboard/revF5/Printrboard.sch
+ *  Schematic (RevF6): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Printrboard%20Rev.F6/schematic.png
+ *  Origin (RevF6): https://raw.githubusercontent.com/lwalkera/printrboard/revF6/Printrboard.sch
  */
 
 /**
diff --git a/Marlin/src/pins/teensy2/pins_SAV_MKI.h b/Marlin/src/pins/teensy2/pins_SAV_MKI.h
index cdba535090..a469bba59b 100644
--- a/Marlin/src/pins/teensy2/pins_SAV_MKI.h
+++ b/Marlin/src/pins/teensy2/pins_SAV_MKI.h
@@ -25,6 +25,9 @@
  *  Rev B  2 JUN 2017
  *
  *  Converted to Arduino pin numbering
+ *
+ *  Schematic: https://green-candy.osdn.jp/external/MarlinFW/board_schematics/SAV%20MkI/SAV_MK-I.pdf
+ *  Origin: https://reprap.org/mediawiki/images/3/3c/SAV_MK-I.pdf
  */
 
 /**
diff --git a/Marlin/src/pins/teensy2/pins_TEENSY2.h b/Marlin/src/pins/teensy2/pins_TEENSY2.h
index efb409bf32..b95e9cae48 100644
--- a/Marlin/src/pins/teensy2/pins_TEENSY2.h
+++ b/Marlin/src/pins/teensy2/pins_TEENSY2.h
@@ -109,6 +109,7 @@
 
 #include "env_validate.h"
 
+// https://reprap.org/wiki/Teensy_Breadboard
 #define BOARD_INFO_NAME "Teensy++2.0"
 
 //
diff --git a/Marlin/src/pins/teensy2/pins_TEENSYLU.h b/Marlin/src/pins/teensy2/pins_TEENSYLU.h
index ab722478fd..294a289cdb 100644
--- a/Marlin/src/pins/teensy2/pins_TEENSYLU.h
+++ b/Marlin/src/pins/teensy2/pins_TEENSYLU.h
@@ -24,6 +24,10 @@
  *  Rev C  2 JUN 2017
  *
  *  Converted to Arduino pin numbering
+ *
+ *  Schematic (1.0): https://green-candy.osdn.jp/external/MarlinFW/board_schematics/Teensylu%20v1.0/schematic.png
+ *  Origin (1.0): https://raw.githubusercontent.com/StephS/Teensylu/master/working/Teensylu-1.0.sch
+ *  (*) Other versions are discouraged by creator.
  */
 
 /**