keyboard/fc660c/fc660c.c

   1 /*
   2 Copyright 2017 Jun Wako <wakojun@gmail.com>
   3
   4 This program is free software: you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation, either version 2 of the License, or
   7 (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 /*
  19  * scan matrix
  20  */
  21 #include <stdint.h>
  22 #include <stdbool.h>
  23 #include <util/delay.h>
  24 #include "print.h"
  25 #include "debug.h"
  26 #include "util.h"
  27 #include "timer.h"
  28 #include "matrix.h"
  29 #include <avr/wdt.h>
  30 #include "suspend.h"
  31 #include "lufa.h"
  32 #include "led.h"
  33 #include "fc660c.h"
  34
  35
  36 static uint32_t matrix_last_modified = 0;
  37
  38 // matrix state buffer(1:on, 0:off)
  39 static matrix_row_t *matrix;
  40 static matrix_row_t *matrix_prev;
  41 static matrix_row_t _matrix0[MATRIX_ROWS];
  42 static matrix_row_t _matrix1[MATRIX_ROWS];
  43
  44
  45 void matrix_init(void)
  46 {
  47 #if 0
  48     debug_enable = true;
  49     debug_keyboard = true;
  50     debug_matrix = true;
  51 #endif
  52
  53     KEY_INIT();
  54
  55     // LEDs on CapsLock and Insert
  56     DDRB  |= (1<<6) | (1<<7);
  57     PORTB |= (1<<6) | (1<<7);
  58
  59     // initialize matrix state: all keys off
  60     for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0x00;
  61     for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0x00;
  62     matrix = _matrix0;
  63     matrix_prev = _matrix1;
  64 }
  65
  66 uint8_t matrix_scan(void)
  67 {
  68     matrix_row_t *tmp;
  69
  70     tmp = matrix_prev;
  71     matrix_prev = matrix;
  72     matrix = tmp;
  73
  74     uint8_t row, col;
  75     for (col = 0; col < MATRIX_COLS; col++) {
  76         SET_COL(col);
  77         for (row = 0; row < MATRIX_ROWS; row++) {
  78             //KEY_SELECT(row, col);
  79             SET_ROW(row);
  80             _delay_us(2);
  81
  82             // Not sure this is needed. This just emulates HHKB controller's behaviour.
  83             if (matrix_prev[row] & (1<<col)) {
  84                 KEY_HYS_ON();
  85             }
  86             _delay_us(10);
  87
  88             // NOTE: KEY_STATE is valid only in 20us after KEY_ENABLE.
  89             // If V-USB interrupts in this section we could lose 40us or so
  90             // and would read invalid value from KEY_STATE.
  91             uint8_t last = TIMER_RAW;
  92
  93             KEY_ENABLE();
  94
  95             // Wait for KEY_STATE outputs its value.
  96             _delay_us(2);
  97
  98             if (KEY_STATE()) {
  99                 matrix[row] &= ~(1<<col);
 100             } else {
 101                 matrix[row] |= (1<<col);
 102             }
 103
 104             // Ignore if this code region execution time elapses more than 20us.
 105             // MEMO: 20[us] * (TIMER_RAW_FREQ / 1000000)[count per us]
 106             // MEMO: then change above using this rule: a/(b/c) = a*1/(b/c) = a*(c/b)
 107             if (TIMER_DIFF_RAW(TIMER_RAW, last) > 20/(1000000/TIMER_RAW_FREQ)) {
 108                 matrix[row] = matrix_prev[row];
 109             }
 110
 111             _delay_us(5);
 112             KEY_HYS_OFF();
 113             KEY_UNABLE();
 114
 115             // NOTE: KEY_STATE keep its state in 20us after KEY_ENABLE.
 116             // This takes 25us or more to make sure KEY_STATE returns to idle state.
 117             _delay_us(75);
 118         }
 119         if (matrix[row] ^ matrix_prev[row]) {
 120             matrix_last_modified = timer_read32();
 121         }
 122     }
 123     return 1;
 124 }
 125
 126 inline
 127 matrix_row_t matrix_get_row(uint8_t row)
 128 {
 129     return matrix[row];
 130 }
 131
 132 void led_set(uint8_t usb_led)
 133 {
 134     if (usb_led & (1<<USB_LED_CAPS_LOCK)) {
 135         PORTB &= ~(1<<6);
 136     } else {
 137         PORTB |=  (1<<6);
 138     }
 139 }