118 lines
3.4 KiB
C
118 lines
3.4 KiB
C
/*
|
|
Copyright 2017 Alex Ong<the.onga@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/>.
|
|
*/
|
|
|
|
/*
|
|
Basic per-key algorithm. Uses an 8-bit counter per key.
|
|
After pressing a key, it immediately changes state, and sets a counter.
|
|
No further inputs are accepted until DEBOUNCE milliseconds have occurred.
|
|
*/
|
|
|
|
#include "debounce.h"
|
|
#include "matrix.h"
|
|
#include "timer.h"
|
|
|
|
#ifndef DEBOUNCE
|
|
#define DEBOUNCE 5
|
|
#endif
|
|
|
|
|
|
#if (MATRIX_COLS <= 8)
|
|
# define ROW_SHIFTER ((uint8_t)1)
|
|
#elif (MATRIX_COLS <= 16)
|
|
# define ROW_SHIFTER ((uint16_t)1)
|
|
#elif (MATRIX_COLS <= 32)
|
|
# define ROW_SHIFTER ((uint32_t)1)
|
|
#endif
|
|
|
|
|
|
|
|
#define debounce_counter_t uint8_t
|
|
|
|
static debounce_counter_t debounce_counters[MATRIX_ROWS*MATRIX_COLS];
|
|
|
|
#define DEBOUNCE_ELAPSED 251
|
|
#define MAX_DEBOUNCE (DEBOUNCE_ELAPSED - 1)
|
|
|
|
void update_debounce_counters(uint8_t num_rows, uint8_t current_time);
|
|
void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, uint8_t current_time);
|
|
|
|
void debounce_init(uint8_t num_rows)
|
|
{
|
|
int i = 0;
|
|
for (uint8_t r = 0; r < MATRIX_ROWS; r++)
|
|
{
|
|
for (uint8_t c = 0; c < MATRIX_COLS; c++)
|
|
{
|
|
debounce_counters[i++] = DEBOUNCE_ELAPSED;
|
|
}
|
|
}
|
|
}
|
|
|
|
void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed)
|
|
{
|
|
uint8_t current_time = timer_read() % MAX_DEBOUNCE;
|
|
update_debounce_counters(num_rows, current_time);
|
|
transfer_matrix_values(raw, cooked, num_rows, current_time);
|
|
}
|
|
|
|
//If the current time is > debounce counter, set the counter to enable input.
|
|
void update_debounce_counters(uint8_t num_rows, uint8_t current_time)
|
|
{
|
|
debounce_counter_t *debounce_pointer = debounce_counters;
|
|
for (uint8_t row = 0; row < num_rows; row++)
|
|
{
|
|
for (uint8_t col = 0; col < MATRIX_COLS; col++)
|
|
{
|
|
if (*debounce_pointer != DEBOUNCE_ELAPSED)
|
|
{
|
|
if (TIMER_DIFF(current_time, *debounce_pointer, MAX_DEBOUNCE) >= DEBOUNCE) {
|
|
*debounce_pointer = DEBOUNCE_ELAPSED;
|
|
}
|
|
}
|
|
debounce_pointer++;
|
|
}
|
|
}
|
|
}
|
|
|
|
// upload from raw_matrix to final matrix;
|
|
void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, uint8_t current_time)
|
|
{
|
|
debounce_counter_t *debounce_pointer = debounce_counters;
|
|
for (uint8_t row = 0; row < num_rows; row++)
|
|
{
|
|
matrix_row_t existing_row = cooked[row];
|
|
matrix_row_t raw_row = raw[row];
|
|
|
|
for (uint8_t col = 0; col < MATRIX_COLS; col++)
|
|
{
|
|
matrix_row_t col_mask = (ROW_SHIFTER << col);
|
|
bool final_value = raw_row & col_mask;
|
|
bool existing_value = existing_row & col_mask;
|
|
if (*debounce_pointer == DEBOUNCE_ELAPSED &&
|
|
(existing_value != final_value))
|
|
{
|
|
*debounce_pointer = current_time;
|
|
existing_row ^= col_mask; //flip the bit.
|
|
}
|
|
debounce_pointer++;
|
|
}
|
|
cooked[row] = existing_row;
|
|
}
|
|
}
|
|
|
|
bool debounce_active()
|
|
{
|
|
return true;
|
|
}
|
|
|