matrix.c

#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include "hal.h"
#include "timer.h"
#include "wait.h"
#include "print.h"
#include "debug.h"
#include "matrix.h"


/*
 * Matt3o's WhiteFox
 * Column pins are input with internal pull-down. Row pins are output and strobe with high.
 * Key is high or 1 when it turns on.
 *
 *     col: { PTD0, PTD1, PTD4, PTD5, PTD6, PTD7, PTC1, PTC2 }
 *     row: { PTB2, PTB3, PTB18, PTB19, PTC0, PTC8, PTC9, PTC10, PTC11 }
 */
/* matrix state(1:on, 0:off) */
static matrix_row_t matrix[MATRIX_ROWS];
static matrix_row_t matrix_debouncing[MATRIX_ROWS];
static bool debouncing = false;
static uint16_t debouncing_time = 0;


void matrix_init(void)
{
    debug_matrix = true;
    /* Column(sense) */
    palSetPadMode(GPIOD, 0,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOD, 1,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOD, 4,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOD, 5,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOD, 6,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOD, 7,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOC, 1,  PAL_MODE_INPUT_PULLDOWN);
    palSetPadMode(GPIOC, 2,  PAL_MODE_INPUT_PULLDOWN);

    /* Row(strobe) */
    palSetPadMode(GPIOB, 2,  PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOB, 3,  PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOB, 18, PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOB, 19, PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOC, 0,  PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOC, 8,  PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOC, 9,  PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOC, 10, PAL_MODE_OUTPUT_PUSHPULL);
    palSetPadMode(GPIOC, 11, PAL_MODE_OUTPUT_PUSHPULL);

    memset(matrix, 0, MATRIX_ROWS);
    memset(matrix_debouncing, 0, MATRIX_ROWS);
}

uint8_t matrix_scan(void)
{
    for (int row = 0; row < MATRIX_ROWS; row++) {
        matrix_row_t data = 0;

        // strobe row
        switch (row) {
            case 0: palSetPad(GPIOB, 2);    break;
            case 1: palSetPad(GPIOB, 3);    break;
            case 2: palSetPad(GPIOB, 18);   break;
            case 3: palSetPad(GPIOB, 19);   break;
            case 4: palSetPad(GPIOC, 0);    break;
            case 5: palSetPad(GPIOC, 8);    break;
            case 6: palSetPad(GPIOC, 9);    break;
            case 7: palSetPad(GPIOC, 10);   break;
            case 8: palSetPad(GPIOC, 11);   break;
        }

        wait_us(1); // need wait to settle pin state

        // read col data: { PTD0, PTD1, PTD4, PTD5, PTD6, PTD7, PTC1, PTC2 }
        data = ((palReadPort(GPIOC) & 0x06UL) << 5) |
               ((palReadPort(GPIOD) & 0xF0UL) >> 2) |
                (palReadPort(GPIOD) & 0x03UL);

        // un-strobe row
        switch (row) {
            case 0: palClearPad(GPIOB, 2);  break;
            case 1: palClearPad(GPIOB, 3);  break;
            case 2: palClearPad(GPIOB, 18); break;
            case 3: palClearPad(GPIOB, 19); break;
            case 4: palClearPad(GPIOC, 0);  break;
            case 5: palClearPad(GPIOC, 8);  break;
            case 6: palClearPad(GPIOC, 9);  break;
            case 7: palClearPad(GPIOC, 10); break;
            case 8: palClearPad(GPIOC, 11); break;
        }

        if (matrix_debouncing[row] != data) {
            matrix_debouncing[row] = data;
            debouncing = true;
            debouncing_time = timer_read();
        }
    }

    if (debouncing && timer_elapsed(debouncing_time) > DEBOUNCE) {
        for (int row = 0; row < MATRIX_ROWS; row++) {
            matrix[row] = matrix_debouncing[row];
        }
        debouncing = false;
    }
    return 1;
}

bool matrix_is_on(uint8_t row, uint8_t col)
{
    return (matrix[row] & (1<<col));
}

matrix_row_t matrix_get_row(uint8_t row)
{
    return matrix[row];
}

void matrix_print(void)
{
    xprintf("\nr/c 01234567\n");
    for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
        xprintf("%X0: ", row);
        matrix_row_t data = matrix_get_row(row);
        for (int col = 0; col < MATRIX_COLS; col++) {
            if (data & (1<<col))
                xprintf("1");
            else
                xprintf("0");
        }
        xprintf("\n");
    }
}