2 Copyright 2017 Alex Ong<the.onga@gmail.com>
3 This program is free software: you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation, either version 2 of the License, or
6 (at your option) any later version.
7 This program is distributed in the hope that it will be useful,
8 but WITHOUT ANY WARRANTY; without even the implied warranty of
9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 GNU General Public License for more details.
11 You should have received a copy of the GNU General Public License
12 along with this program. If not, see <http://www.gnu.org/licenses/>.
16 Basic per-key algorithm. Uses an 8-bit counter per key.
17 After pressing a key, it immediately changes state, and sets a counter.
18 No further inputs are accepted until DEBOUNCE milliseconds have occurred.
30 #if (MATRIX_COLS <= 8)
31 # define ROW_SHIFTER ((uint8_t)1)
32 #elif (MATRIX_COLS <= 16)
33 # define ROW_SHIFTER ((uint16_t)1)
34 #elif (MATRIX_COLS <= 32)
35 # define ROW_SHIFTER ((uint32_t)1)
40 #define debounce_counter_t uint8_t
42 static debounce_counter_t debounce_counters[MATRIX_ROWS*MATRIX_COLS];
44 #define DEBOUNCE_ELAPSED 251
45 #define MAX_DEBOUNCE (DEBOUNCE_ELAPSED - 1)
47 void update_debounce_counters(uint8_t num_rows, uint8_t current_time);
48 void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, uint8_t current_time);
50 void debounce_init(uint8_t num_rows)
53 for (uint8_t r = 0; r < MATRIX_ROWS; r++)
55 for (uint8_t c = 0; c < MATRIX_COLS; c++)
57 debounce_counters[i++] = DEBOUNCE_ELAPSED;
62 void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed)
64 uint8_t current_time = timer_read() % MAX_DEBOUNCE;
65 update_debounce_counters(num_rows, current_time);
66 transfer_matrix_values(raw, cooked, num_rows, current_time);
69 //If the current time is > debounce counter, set the counter to enable input.
70 void update_debounce_counters(uint8_t num_rows, uint8_t current_time)
72 debounce_counter_t *debounce_pointer = debounce_counters;
73 for (uint8_t row = 0; row < num_rows; row++)
75 for (uint8_t col = 0; col < MATRIX_COLS; col++)
77 if (*debounce_pointer != DEBOUNCE_ELAPSED)
79 if (TIMER_DIFF(current_time, *debounce_pointer, MAX_DEBOUNCE) >= DEBOUNCE) {
80 *debounce_pointer = DEBOUNCE_ELAPSED;
88 // upload from raw_matrix to final matrix;
89 void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, uint8_t current_time)
91 debounce_counter_t *debounce_pointer = debounce_counters;
92 for (uint8_t row = 0; row < num_rows; row++)
94 matrix_row_t existing_row = cooked[row];
95 matrix_row_t raw_row = raw[row];
97 for (uint8_t col = 0; col < MATRIX_COLS; col++)
99 matrix_row_t col_mask = (ROW_SHIFTER << col);
100 bool final_value = raw_row & col_mask;
101 bool existing_value = existing_row & col_mask;
102 if (*debounce_pointer == DEBOUNCE_ELAPSED &&
103 (existing_value != final_value))
105 *debounce_pointer = current_time;
106 existing_row ^= col_mask; //flip the bit.
110 cooked[row] = existing_row;
114 bool debounce_active()