#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 *prev_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)
{
- // Column: input w/pullup
+ // initialize row and col
+ unselect_rows();
DDRB = 0x00;
PORTB = 0xFF;
- // Row: Hi-Z(unselected)
- // PD:0,1,2,3,6,7
- // PC:6,7
- // PF:7
- DDRD = 0x00;
- PORTD = 0x00;
- DDRC = 0x00;
- PORTC = 0x00;
- DDRF = 0x00;
- PORTF = 0x00;
-
- for (int i=0; i < MATRIX_ROWS; i++) {
- _matrix0[i] = 0xFF;
- _matrix1[i] = 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;
- prev_matrix = _matrix1;
+ matrix_prev = _matrix1;
}
uint8_t matrix_scan(void)
uint8_t row, state;
uint8_t *tmp;
- tmp = prev_matrix;
- prev_matrix = matrix;
+ 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) {
* THE SOFTWARE.
*/
+#include <stdbool.h>
#include <avr/io.h>
#include <avr/pgmspace.h>
#include <avr/interrupt.h>
#include <util/delay.h>
+
#include "usb_keyboard_debug.h"
#include "print.h"
#include "matrix.h"
int main(void)
{
- uint8_t modified = 0;
+ bool modified = false;
+ bool has_ghost = false;
uint8_t key_index = 0;
// set for 16 MHz clock
while (1) {
uint8_t row, col, code;
- modified = 0;
-
matrix_scan();
- keyboard_modifier_keys = 0;
- for (int i = 0; i < 6; i++)
- keyboard_keys[i] = KB_NO;
- key_index = 0;
+ modified = matrix_is_modified();
+ has_ghost = matrix_has_ghost();
- for (row = 0; row < MATRIX_ROWS; row++) {
- if (matrix[row] != prev_matrix[row]) {
- modified = 1;
- }
+ // doesnt send keys during ghost occurs
+ if (modified && !has_ghost) {
+ key_index = 0;
+ keyboard_modifier_keys = 0;
+ for (int i = 0; i < 6; i++) keyboard_keys[i] = KB_NO;
- for (col = 0; col < MATRIX_COLS; col++) {
- if (matrix[row] & 1<<col) continue;
- code = get_keycode(row, col);
-
- // Modifier keycode: 0xE0-0xE7
- if (KB_LCTRL <= code && code <= KB_RGUI) {
- keyboard_modifier_keys |= 1<<(code&0x07);
- } else {
- if (key_index < 6) {
- keyboard_keys[key_index] = code;
+ for (row = 0; row < MATRIX_ROWS; row++) {
+ for (col = 0; col < MATRIX_COLS; col++) {
+ if (matrix[row] & 1<<col) continue;
+
+ code = get_keycode(row, col);
+ if (KB_LCTRL <= code && code <= KB_RGUI) {
+ // modifier keycode: 0xE0-0xE7
+ keyboard_modifier_keys |= 1<<(code & 0x07);
+ } else {
+ if (key_index < 6)
+ keyboard_keys[key_index] = code;
+ key_index++;
}
- key_index++;
}
+ }
+ if (key_index > 6) {
+ //Rollover
}
- }
- if (key_index > 6) {
- //Rollover
- }
-
+ usb_keyboard_send();
- // if any keypresses were detected, reset the idle counter
+ // variables shared with interrupt routines must be
+ // accessed carefully so the interrupt routine doesn't
+ // try to use the variable in the middle of our access
+ cli();
+ idle_count = 0;
+ sei();
+ }
+
+ // print matrix state for debug
if (modified) {
- print(" 01234567\n");
+ print("r/c 01234567\n");
for (row = 0; row < MATRIX_ROWS; row++) {
- phex(row); print(": "); pbin_reverse(matrix[row]); print("\n");
+ phex(row); print(": ");
+ pbin_reverse(matrix[row]);
+ if (matrix_has_ghost_in_row(row)) {
+ print(" <ghost");
+ }
+ print("\n");
}
print("keys: ");
for (int i = 0; i < 6; i++) { phex(keyboard_keys[i]); print(" "); }
print("\n");
print("mod: "); phex(keyboard_modifier_keys); print("\n");
- usb_keyboard_send();
-
- // variables shared with interrupt routines must be
- // accessed carefully so the interrupt routine doesn't
- // try to use the variable in the middle of our access
- cli();
- idle_count = 0;
- sei();
}
// now the current pins will be the previous, and