qmk_firmware/keyboards/evyd13/wasdat/matrix.c

137 lines
3.4 KiB
C

/*
Copyright 2012-2018 Jun Wako, Jack Humbert, Yiancar
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 row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
static const pin_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
/* Columns 6-12 use a 74HC138 3-to-8 demultiplexer.
*
* 0: C7
* 1: B6
* 2: C6
* 3: B4
* 4: B5
* 5: D7
*
* A2 A1 A0
* D0 D1 D2
* 6: 1 1 1
* 7: 1 1 0
* 8: 1 0 1
* 9: 1 0 0
* 10: 0 1 1
* 11: 0 1 0
* 12: 0 0 1
*
* 13: D3
* 14: B7
* 15: B3
*/
static void select_col(uint8_t col) {
if (col_pins[col] != NO_PIN) {
writePinLow(col_pins[col]);
} else {
sn74x138_set_addr(13 - col);
}
}
static void unselect_col(uint8_t col) {
if (col_pins[col] != NO_PIN) {
setPinOutput(col_pins[col]);
writePinHigh(col_pins[col]);
} else {
sn74x138_set_addr(0);
}
}
static void unselect_cols(void) {
// Native
for (uint8_t x = 0; x < MATRIX_COLS; x++) {
if (col_pins[x] != NO_PIN) {
setPinOutput(col_pins[x]);
writePinHigh(col_pins[x]);
}
}
// Demultiplexer
sn74x138_set_addr(0);
}
static void init_pins(void) {
unselect_cols();
for (uint8_t x = 0; x < MATRIX_ROWS; x++) {
setPinInputHigh(row_pins[x]);
}
}
static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
bool matrix_changed = false;
// Select col and wait for col selection to stabilize
select_col(current_col);
matrix_io_delay();
// For each row...
for (uint8_t row_index = 0; row_index < MATRIX_ROWS; row_index++) {
// Store last value of row prior to reading
matrix_row_t last_row_value = current_matrix[row_index];
// Check row pin state
if (readPin(row_pins[row_index]) == 0) {
// Pin LO, set col bit
current_matrix[row_index] |= (MATRIX_ROW_SHIFTER << current_col);
} else {
// Pin HI, clear col bit
current_matrix[row_index] &= ~(MATRIX_ROW_SHIFTER << current_col);
}
// Determine if the matrix changed state
if ((last_row_value != current_matrix[row_index]) && !(matrix_changed)) {
matrix_changed = true;
}
}
// Unselect col
unselect_col(current_col);
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 col, read rows
for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
changed |= read_rows_on_col(current_matrix, current_col);
}
return changed;
}