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WIP: add parallel port example

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Jeremy Soller 2019-12-31 21:59:04 -07:00
parent 4a8943183c
commit 3675419ee3
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src/board/arduino/mega2560/parallel.c Normal file
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// High resolution pinout can be found here:
// https://osoyoo.com/wp-content/uploads/2017/08/arduino_mega_2560_pinout.png
#include <stdint.h>
#include <stdio.h>
#include <arch/gpio.h>
// Mapping of 24-pin ribbon cable to GPIOs
static struct Gpio gpios[24] = {
GPIO(B, 1), GPIO(B, 0),
GPIO(B, 3), GPIO(B, 2),
GPIO(L, 1), GPIO(L, 0),
GPIO(L, 3), GPIO(L, 2),
GPIO(L, 5), GPIO(L, 4),
GPIO(L, 7), GPIO(L, 6),
GPIO(G, 1), GPIO(G, 0),
GPIO(D, 7), GPIO(G, 2),
GPIO(C, 1), GPIO(C, 0),
GPIO(C, 3), GPIO(C, 2),
GPIO(C, 5), GPIO(C, 4),
GPIO(C, 7), GPIO(C, 6)
};
struct ParallelPins {
// Data (KSO0 - KSO7) - bi-directional
uint8_t d0;
uint8_t d1;
uint8_t d2;
uint8_t d3;
uint8_t d4;
uint8_t d5;
uint8_t d6;
uint8_t d7;
// Wait# (KSO9) - input
// low to indicate cycle may begin, high to indicate cycle may end
uint8_t wait_n;
// Write# (KSI0) - output
// low to indicate write cycle, high to indicate read cycle
uint8_t write_n;
// DataStrobe# (KSI1) - output
// low indicates a data cycle
uint8_t data_n;
// Reset# (KSI2) - output
// low requests device reset
uint8_t reset_n;
// AddressStrobe# (KSI3) - output
// low indicates an address cycle
uint8_t addr_n;
// Strap0 (KSI4)
// 1K-Ohm pull-down resistor
uint8_t strap_0;
// Strap1 (KSI5)
// 1K-Ohm pull-down resistor
uint8_t strap_1;
};
// Mapping of 24-pin ribbon cable to parallel pins. See schematic
static struct ParallelPins pins = {
.d0 = 1,
.d1 = 2,
.d2 = 3,
.d3 = 7,
.d4 = 9,
.d5 = 10,
.d6 = 13,
.d7 = 16,
.wait_n = 18,
.write_n = 4,
.data_n = 5,
.reset_n = 6,
.addr_n = 8,
.strap_0 = 11,
.strap_1 = 12,
};
#define PIN_GPIO(N) \
struct Gpio * N = NULL; \
if (pins.N > 0 && pins.N < 24) N = &gpios[pins.N - 1]; \
if (!N) return; \
gpio_set_dir(N, false); \
gpio_set(N, false);
void parallel(void) {
PIN_GPIO(d0);
PIN_GPIO(d1);
PIN_GPIO(d2);
PIN_GPIO(d3);
PIN_GPIO(d4);
PIN_GPIO(d5);
PIN_GPIO(d6);
PIN_GPIO(d7);
PIN_GPIO(wait_n);
PIN_GPIO(write_n);
PIN_GPIO(data_n);
PIN_GPIO(reset_n);
PIN_GPIO(addr_n);
PIN_GPIO(strap_0);
PIN_GPIO(strap_1);
}