qmk-firmware/matrix.c

183 lines
3.9 KiB
C

/*
* scan matrix
*/
#include <avr/io.h>
#include <util/delay.h>
#include "keymap.h"
#include "matrix.h"
#include "print.h"
// matrix is active low. (key on: 0/key off: 1)
// row: Hi-Z(unselected)/low output(selected)
// PD:0,1,2,3,6,7/PC:6,7/PF:7
// col: input w/pullup
// PB:0-8
// matrix state buffer
uint8_t *matrix;
uint8_t *matrix_prev;
static uint8_t _matrix0[MATRIX_ROWS];
static uint8_t _matrix1[MATRIX_ROWS];
static uint8_t read_col(void);
static void unselect_rows(void);
static void select_row(uint8_t row);
// this must be called once before matrix_scan.
void matrix_init(void)
{
// initialize row and col
unselect_rows();
DDRB = 0x00;
PORTB = 0xFF;
// initialize matrix state: all keys off
for (int i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0xFF;
for (int i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0xFF;
matrix = _matrix0;
matrix_prev = _matrix1;
}
uint8_t matrix_scan(void)
{
uint8_t row, state;
uint8_t *tmp;
tmp = matrix_prev;
matrix_prev = matrix;
matrix = tmp;
for (row = 0; row < MATRIX_ROWS; row++) {
select_row(row);
_delay_us(30); // without this wait read unstable value.
state = read_col();
unselect_rows();
matrix[row] = state;
}
return 1;
}
bool matrix_is_modified(void) {
for (int i=0; i <MATRIX_ROWS; i++) {
if (matrix[i] != matrix_prev[i])
return true;
}
return false;
}
bool matrix_has_ghost(void) {
for (int i=0; i <MATRIX_ROWS; i++) {
if (matrix_has_ghost_in_row(i))
return true;
}
return false;
}
bool matrix_has_ghost_in_row(uint8_t row) {
uint8_t state = ~matrix[row];
// no ghost exists in case less than 2 keys on
if (((state - 1) & state) == 0)
return false;
// ghost exists in case same state as other row
for (int i=0; i < MATRIX_ROWS; i++) {
if (i == row) continue;
if ((~matrix[i] & state) == state) return true;
}
return false;
}
static uint8_t read_col(void)
{
return PINB;
}
static void unselect_rows(void) {
DDRD = 0x00;
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
}
static void select_row(uint8_t row)
{
switch (row) {
case 0:
DDRD = (1<<0);
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 1:
DDRD = (1<<1);
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 2:
DDRD = (1<<2);
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 3:
DDRD = (1<<3);
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 4:
DDRD = (1<<6);
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 5:
DDRD = (1<<7);
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 6:
DDRD = 0x00;
PORTD = 0x00;
DDRC = (1<<6);
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 7:
DDRD = 0x00;
PORTD = 0x00;
DDRC = (1<<7);
PORTC = 0x00;
DDRF = 0x00;
PORTF = 0x00;
break;
case 8:
DDRD = 0x00;
PORTD = 0x00;
DDRC = 0x00;
PORTC = 0x00;
DDRF = (1<<7);
PORTF = 0x00;
break;
}
}