97 lines
2.6 KiB
C
97 lines
2.6 KiB
C
/*
|
|
Copyright 2022 somepin
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include <stdbool.h>
|
|
#include "matrix.h"
|
|
#include "quantum.h"
|
|
#include "sn74x138.h"
|
|
|
|
static const pin_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
|
|
|
|
/* All rows use a 74HC138 3 to 8 bit demultiplexer.
|
|
*
|
|
* A2 A1 A0
|
|
* D0 D1 D2
|
|
* 0: 0 0 0
|
|
* 1: 0 0 1
|
|
* 2: 0 1 0
|
|
* 3: 0 1 1
|
|
* 4: 1 0 0
|
|
* 5: 1 0 1
|
|
* 6: 1 1 0
|
|
*/
|
|
static void select_row(uint8_t row) {
|
|
sn74x138_set_addr(row);
|
|
}
|
|
|
|
static void init_pins(void) {
|
|
for (uint8_t x = 0; x < MATRIX_COLS; x++) {
|
|
setPinInputHigh(col_pins[x]);
|
|
}
|
|
}
|
|
|
|
static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
|
|
bool matrix_changed = false;
|
|
|
|
// Store last value of row prior to reading
|
|
matrix_row_t last_row_value = current_matrix[current_row];
|
|
|
|
// Start with a clear matrix row
|
|
current_matrix[current_row] = 0;
|
|
|
|
// Select row and wait for row selection to stabilize
|
|
select_row(current_row);
|
|
matrix_io_delay();
|
|
|
|
// For each col...
|
|
matrix_row_t row_shifter = MATRIX_ROW_SHIFTER;
|
|
for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
|
|
|
|
// Select the col pin to read (active low)
|
|
uint8_t pin_state = readPin(col_pins[col_index]);
|
|
|
|
// Populate the matrix row with the state of the col pin
|
|
current_matrix[current_row] |= pin_state ? 0 : (row_shifter << col_index);
|
|
}
|
|
|
|
// Determine if matrix changed state
|
|
if ((last_row_value != current_matrix[current_row]) && !(matrix_changed)) {
|
|
matrix_changed = true;
|
|
}
|
|
|
|
return matrix_changed;
|
|
}
|
|
|
|
void matrix_init_custom(void) {
|
|
// initialize demultiplexer
|
|
sn74x138_init();
|
|
// initialize key pins
|
|
init_pins();
|
|
}
|
|
|
|
bool matrix_scan_custom(matrix_row_t current_matrix[]) {
|
|
bool changed = false;
|
|
|
|
// Set row, read cols
|
|
for (uint8_t current_row = 0; current_row < MATRIX_ROWS; current_row++) {
|
|
changed |= read_cols_on_row(current_matrix, current_row);
|
|
}
|
|
|
|
return changed;
|
|
}
|