/* Copyright 2017 Luiz Ribeiro <luizribeiro@gmail.com> 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 <avr/io.h> #include <util/delay.h> #include "matrix.h" #ifndef DEBOUNCE # define DEBOUNCE 5 #endif static uint8_t debouncing = DEBOUNCE; static matrix_row_t matrix[MATRIX_ROWS]; static matrix_row_t matrix_debouncing[MATRIX_ROWS]; void matrix_init(void) { // all outputs for rows high DDRB = 0xFF; PORTB = 0xFF; // all inputs for columns DDRA = 0x00; DDRC &= ~(0x111111<<2); DDRD &= ~(1<<PIND7); // all columns are pulled-up PORTA = 0xFF; PORTC |= (0b111111<<2); PORTD |= (1<<PIND7); // initialize matrix state: all keys off for (uint8_t row = 0; row < MATRIX_ROWS; row++) { matrix[row] = 0x00; matrix_debouncing[row] = 0x00; } } void matrix_set_row_status(uint8_t row) { DDRB = (1 << row); PORTB = ~(1 << row); } uint8_t bit_reverse(uint8_t x) { x = ((x >> 1) & 0x55) | ((x << 1) & 0xaa); x = ((x >> 2) & 0x33) | ((x << 2) & 0xcc); x = ((x >> 4) & 0x0f) | ((x << 4) & 0xf0); return x; } uint8_t matrix_scan(void) { for (uint8_t row = 0; row < MATRIX_ROWS; row++) { matrix_set_row_status(row); _delay_us(5); matrix_row_t cols = ( // cols 0..7, PORTA 0 -> 7 (~PINA) & 0xFF ) | ( // cols 8..13, PORTC 7 -> 0 bit_reverse((~PINC) & 0xFF) << 8 ) | ( // col 14, PORTD 7 ((~PIND) & (1 << PIND7)) << 7 ); if (matrix_debouncing[row] != cols) { matrix_debouncing[row] = cols; debouncing = DEBOUNCE; } } if (debouncing) { if (--debouncing) { _delay_ms(1); } else { for (uint8_t i = 0; i < MATRIX_ROWS; i++) { matrix[i] = matrix_debouncing[i]; } } } matrix_scan_user(); return 1; } inline matrix_row_t matrix_get_row(uint8_t row) { return matrix[row]; } void matrix_print(void) { }