keyboard/alps64/matrix.c

   1 /*
   2 Copyright 2012 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 <avr/io.h>
  24 #include <util/delay.h>
  25 #include "print.h"
  26 #include "debug.h"
  27 #include "util.h"
  28 #include "matrix.h"
  29
  30
  31 #ifndef DEBOUNCE
  32 #   define DEBOUNCE     5
  33 #endif
  34 static uint8_t debouncing = DEBOUNCE;
  35
  36 /* matrix state(1:on, 0:off) */
  37 static matrix_row_t matrix[MATRIX_ROWS];
  38 static matrix_row_t matrix_debouncing[MATRIX_ROWS];
  39
  40 static matrix_row_t read_cols(void);
  41 static void init_cols(void);
  42 static void unselect_rows(void);
  43 static void select_row(uint8_t row);
  44
  45
  46 inline
  47 uint8_t matrix_rows(void)
  48 {
  49     return MATRIX_ROWS;
  50 }
  51
  52 inline
  53 uint8_t matrix_cols(void)
  54 {
  55     return MATRIX_COLS;
  56 }
  57
  58 #define LED_ON()    do { DDRC |= (1<<5); PORTC |= (1<<5); } while (0)
  59 #define LED_OFF()   do { DDRC &= ~(1<<5); PORTC &= ~(1<<5); } while (0)
  60 #define LED_TGL()   do { DDRC |= (1<<5); PINC |= (1<<5); } while (0)
  61
  62 void matrix_init(void)
  63 {
  64     // initialize row and col
  65     unselect_rows();
  66     init_cols();
  67
  68     // initialize matrix state: all keys off
  69     for (uint8_t i=0; i < MATRIX_ROWS; i++) {
  70         matrix[i] = 0;
  71         matrix_debouncing[i] = 0;
  72     }
  73
  74     //debug
  75     debug_matrix = true;
  76     LED_ON();
  77     _delay_ms(500);
  78     LED_OFF();
  79 }
  80
  81 uint8_t matrix_scan(void)
  82 {
  83     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
  84         select_row(i);
  85         _delay_us(30);  // without this wait read unstable value.
  86         matrix_row_t cols = read_cols();
  87         if (matrix_debouncing[i] != cols) {
  88             matrix_debouncing[i] = cols;
  89             if (debouncing) {
  90                 debug("bounce!: "); debug_hex(debouncing); debug("\n");
  91             }
  92             debouncing = DEBOUNCE;
  93         }
  94         unselect_rows();
  95     }
  96
  97     if (debouncing) {
  98         if (--debouncing) {
  99             _delay_ms(1);
 100         } else {
 101             for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 102                 matrix[i] = matrix_debouncing[i];
 103             }
 104         }
 105     }
 106
 107     return 1;
 108 }
 109
 110 inline
 111 bool matrix_is_on(uint8_t row, uint8_t col)
 112 {
 113     return (matrix[row] & ((matrix_row_t)1<<col));
 114 }
 115
 116 inline
 117 matrix_row_t matrix_get_row(uint8_t row)
 118 {
 119     return matrix[row];
 120 }
 121
 122 void matrix_print(void)
 123 {
 124     print("\nr/c 0123456789ABCDEF\n");
 125     for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
 126         phex(row); print(": ");
 127         pbin_reverse16(matrix_get_row(row));
 128         print("\n");
 129     }
 130 }
 131
 132 /* Column pin configuration
 133  * col: 0   1   2   3   4   5   6   7
 134  * pin: B0  B1  B2  B3  B4  B5  B6  B7
 135  */
 136 static void  init_cols(void)
 137 {
 138     // Input with pull-up(DDR:0, PORT:1)
 139     DDRB  &= ~0b11111111;
 140     PORTB |=  0b11111111;
 141 }
 142
 143 /* Returns status of switches(1:on, 0:off) */
 144 static matrix_row_t read_cols(void)
 145 {
 146     // Invert because PIN indicates 'switch on' with low(0) and 'off' with high(1)
 147     return ~PINB;
 148 }
 149
 150 /* Row pin configuration
 151  * row: 0   1   2   3   4   5   6   7
 152  * pin: D0  D1  D2  D3  D4  D5  D6  C2
 153  */
 154 static void unselect_rows(void)
 155 {
 156     // Hi-Z(DDR:0, PORT:0) to unselect
 157     DDRD  &= ~0b01111111;
 158     PORTD &= ~0b01111111;
 159     DDRC  &= ~0b00000100;
 160     PORTC &= ~0b00000100;
 161 }
 162
 163 static void select_row(uint8_t row)
 164 {
 165     // Output low(DDR:1, PORT:0) to select
 166     switch (row) {
 167         case 0:
 168             DDRD  |= (1<<0);
 169             PORTD &= ~(1<<0);
 170             break;
 171         case 1:
 172             DDRD  |= (1<<1);
 173             PORTD &= ~(1<<1);
 174             break;
 175         case 2:
 176             DDRD  |= (1<<2);
 177             PORTD &= ~(1<<2);
 178             break;
 179         case 3:
 180             DDRD  |= (1<<3);
 181             PORTD &= ~(1<<3);
 182             break;
 183         case 4:
 184             DDRD  |= (1<<4);
 185             PORTD &= ~(1<<4);
 186             break;
 187         case 5:
 188             DDRD  |= (1<<5);
 189             PORTD &= ~(1<<5);
 190             break;
 191         case 6:
 192             DDRD  |= (1<<6);
 193             PORTD &= ~(1<<6);
 194             break;
 195         case 7:
 196             DDRC  |= (1<<2);
 197             PORTC &= ~(1<<2);
 198             break;
 199     }
 200 }