qmk-firmware/hhkb/matrix.c

140 lines
3.1 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)
//
// HHKB has no ghost and no bounce.
// row: HC4051 select input channel(0-8)
// PB0, PB1, PB2(A, B, C)
// col: LS145 select low output line(0-8)
// PB3, PB4, PB5, PB6(A, B, C, D)
// use D as ENABLE: (enable: 0/unenable: 1)
// key: KEY: (on: 0/ off:1)
// UNKNOWN: unknown whether input or output
// PE6,PE7(KEY, UNKNOWN)
#define COL_ENABLE (1<<6)
#define KEY_SELELCT(ROW, COL) (PORTB = COL_ENABLE|(((COL)&0x07)<<3)|((ROW)&0x07))
#define KEY_ENABLE (PORTB &= ~COL_ENABLE)
#define KEY_UNABLE (PORTB |= COL_ENABLE)
#define KEY_ON ((PINE&(1<<6)) ? false : true)
// matrix state buffer
uint8_t *matrix;
uint8_t *matrix_prev;
static uint8_t _matrix0[MATRIX_ROWS];
static uint8_t _matrix1[MATRIX_ROWS];
static bool matrix_has_ghost_in_row(int row);
static int bit_pop(uint8_t bits);
inline
int matrix_rows(void) {
return MATRIX_ROWS;
}
inline
int matrix_cols(void) {
return MATRIX_COLS;
}
// this must be called once before matrix_scan.
void matrix_init(void)
{
// row & col output(PB0-6)
DDRB = 0xFF;
PORTB = KEY_SELELCT(0, 0);
// KEY & VALID input with pullup(PE6,7)
DDRE = 0x3F;
PORTE = 0xC0;
// 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;
}
int matrix_scan(void)
{
uint8_t *tmp;
tmp = matrix_prev;
matrix_prev = matrix;
matrix = tmp;
for (int row = 0; row < MATRIX_ROWS; row++) {
for (int col = 0; col < MATRIX_COLS; col++) {
KEY_SELELCT(row, col);
_delay_us(50); // from logic analyzer chart
KEY_ENABLE;
_delay_us(10); // from logic analyzer chart
if (KEY_ON) {
matrix[row] &= ~(1<<col);
} else {
matrix[row] |= (1<<col);
}
KEY_UNABLE;
_delay_us(150); // from logic analyzer chart
}
}
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;
}
inline
bool matrix_has_ghost(void) {
return false;
}
inline
uint16_t matrix_get_row(int row) {
return matrix[row];
}
void matrix_print(void) {
print("\nr/c 01234567\n");
for (int row = 0; row < matrix_rows(); row++) {
phex(row); print(": ");
pbin_reverse(matrix_get_row(row));
if (matrix_has_ghost_in_row(row)) {
print(" <ghost");
}
print("\n");
}
}
int matrix_key_count(void) {
int count = 0;
for (int i = 0; i < MATRIX_ROWS; i++) {
count += bit_pop(~matrix[i]);
}
return count;
}
inline
static bool matrix_has_ghost_in_row(int row) {
return false;
}
static int bit_pop(uint8_t bits) {
int c;
for (c = 0; bits; c++)
bits &= bits -1;
return c;
}