matrix.c (2695B)
- /* Copyright 2022 mohoyt
- *
- * 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 "matrix.h"
- #include "wait.h"
- #define COL_SHIFTER ((uint32_t)1)
- // Column pins
- static const uint8_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
- static const uint8_t col_pins[MATRIX_MUX_COLS] = MATRIX_COL_MUX_PINS;
- // Internal functions
- static void init_pins(void) {
- // Set cols to outputs, low
- for (uint8_t pin = 0; pin < MATRIX_MUX_COLS; pin++) {
- gpio_set_pin_output(col_pins[pin]);
- }
- // Unselect cols
- for (uint8_t bit = 0; bit < MATRIX_MUX_COLS; bit++) {
- gpio_write_pin_low(col_pins[bit]);
- }
- // Set rows to input, pullup
- for (uint8_t pin = 0; pin < MATRIX_ROWS; pin++) {
- gpio_set_pin_input_high(row_pins[pin]);
- }
- }
- static void select_col(uint8_t col)
- {
- for (uint8_t bit = 0; bit < MATRIX_MUX_COLS; bit++) {
- uint8_t state = (col & (0b1 << bit)) >> bit;
- gpio_write_pin(col_pins[bit], state);
- }
- }
- static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col)
- {
- bool matrix_changed = false;
- select_col(current_col);
- wait_us(5);
- // Read each row sequentially
- for(uint8_t row_index = 0; row_index < MATRIX_ROWS; row_index++)
- {
- matrix_row_t last_row_value = current_matrix[row_index];
- if (!gpio_read_pin(row_pins[row_index]))
- {
- current_matrix[row_index] |= (COL_SHIFTER << current_col);
- }
- else
- {
- current_matrix[row_index] &= ~(COL_SHIFTER << current_col);
- }
- if ((last_row_value != current_matrix[row_index]) && !(matrix_changed))
- {
- matrix_changed = true;
- }
- }
- return matrix_changed;
- }
- // Matrix scan functions
- void matrix_init_custom(void) {
- 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 (uint8_t)changed;
- }