macway/matrix.c

   1 /*
   2 Copyright 2011 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 #if (MATRIX_COLS > 16)
  32 #   error "MATRIX_COLS must not exceed 16"
  33 #endif
  34 #if (MATRIX_ROWS > 255)
  35 #   error "MATRIX_ROWS must not exceed 255"
  36 #endif
  37
  38
  39 #ifndef DEBOUNCE
  40 #   define DEBOUNCE     0
  41 #endif
  42 static uint8_t debouncing = DEBOUNCE;
  43
  44 // matrix state buffer(1:on, 0:off)
  45 #if (MATRIX_COLS <= 8)
  46 static uint8_t *matrix;
  47 static uint8_t *matrix_prev;
  48 static uint8_t _matrix0[MATRIX_ROWS];
  49 static uint8_t _matrix1[MATRIX_ROWS];
  50 #else
  51 static uint16_t *matrix;
  52 static uint16_t *matrix_prev;
  53 static uint16_t _matrix0[MATRIX_ROWS];
  54 static uint16_t _matrix1[MATRIX_ROWS];
  55 #endif
  56
  57 #ifdef MATRIX_HAS_GHOST
  58 static bool matrix_has_ghost_in_row(uint8_t row);
  59 #endif
  60 static uint8_t read_col(void);
  61 static void unselect_rows(void);
  62 static void select_row(uint8_t row);
  63
  64
  65 inline
  66 uint8_t matrix_rows(void)
  67 {
  68     return MATRIX_ROWS;
  69 }
  70
  71 inline
  72 uint8_t matrix_cols(void)
  73 {
  74     return MATRIX_COLS;
  75 }
  76
  77 void matrix_init(void)
  78 {
  79     // initialize row and col
  80     unselect_rows();
  81     // Input with pull-up(DDR:0, PORT:1)
  82     DDRB = 0x00;
  83     PORTB = 0xFF;
  84
  85     // initialize matrix state: all keys off
  86     for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0x00;
  87     for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0x00;
  88     matrix = _matrix0;
  89     matrix_prev = _matrix1;
  90 }
  91
  92 uint8_t matrix_scan(void)
  93 {
  94     if (!debouncing) {
  95         uint8_t *tmp = matrix_prev;
  96         matrix_prev = matrix;
  97         matrix = tmp;
  98     }
  99
 100     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 101         unselect_rows();
 102         select_row(i);
 103         _delay_us(30);  // without this wait read unstable value.
 104         if (matrix[i] != (uint8_t)~read_col()) {
 105             matrix[i] = (uint8_t)~read_col();
 106             if (debouncing) {
 107                 debug("bounce!: "); debug_hex(debouncing); print("\n");
 108             }
 109             debouncing = DEBOUNCE;
 110         }
 111     }
 112     unselect_rows();
 113
 114     if (debouncing) {
 115         debouncing--;
 116     }
 117
 118     return 1;
 119 }
 120
 121 bool matrix_is_modified(void)
 122 {
 123     if (debouncing) return false;
 124     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 125         if (matrix[i] != matrix_prev[i]) {
 126             return true;
 127         }
 128     }
 129     return false;
 130 }
 131
 132 inline
 133 bool matrix_has_ghost(void)
 134 {
 135 #ifdef MATRIX_HAS_GHOST
 136     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 137         if (matrix_has_ghost_in_row(i))
 138             return true;
 139     }
 140 #endif
 141     return false;
 142 }
 143
 144 inline
 145 bool matrix_is_on(uint8_t row, uint8_t col)
 146 {
 147     return (matrix[row] & (1<<col));
 148 }
 149
 150 inline
 151 #if (MATRIX_COLS <= 8)
 152 uint8_t matrix_get_row(uint8_t row)
 153 #else
 154 uint16_t matrix_get_row(uint8_t row)
 155 #endif
 156 {
 157     return matrix[row];
 158 }
 159
 160 void matrix_print(void)
 161 {
 162     print("\nr/c 01234567\n");
 163     for (uint8_t row = 0; row < matrix_rows(); row++) {
 164         phex(row); print(": ");
 165 #if (MATRIX_COLS <= 8)
 166         pbin_reverse(matrix_get_row(row));
 167 #else
 168         pbin_reverse16(matrix_get_row(row));
 169 #endif
 170 #ifdef MATRIX_HAS_GHOST
 171         if (matrix_has_ghost_in_row(row)) {
 172             print(" <ghost");
 173         }
 174 #endif
 175         print("\n");
 176     }
 177 }
 178
 179 uint8_t matrix_key_count(void)
 180 {
 181     uint8_t count = 0;
 182     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 183 #if (MATRIX_COLS <= 8)
 184         count += bitpop(matrix[i]);
 185 #else
 186         count += bitpop16(matrix[i]);
 187 #endif
 188     }
 189     return count;
 190 }
 191
 192 #ifdef MATRIX_HAS_GHOST
 193 inline
 194 static bool matrix_has_ghost_in_row(uint8_t row)
 195 {
 196     // no ghost exists in case less than 2 keys on
 197     if (((matrix[row] - 1) & matrix[row]) == 0)
 198         return false;
 199
 200     // ghost exists in case same state as other row
 201     for (uint8_t i=0; i < MATRIX_ROWS; i++) {
 202         if (i != row && (matrix[i] & matrix[row]) == matrix[row])
 203             return true;
 204     }
 205     return false;
 206 }
 207 #endif
 208
 209 inline
 210 static uint8_t read_col(void)
 211 {
 212     return PINB;
 213 }
 214
 215 inline
 216 static void unselect_rows(void)
 217 {
 218     // Hi-Z(DDR:0, PORT:0) to unselect
 219     DDRC  &= ~0b11000000; // PC: 7,6
 220     PORTC &= ~0b11000000;
 221     DDRD  &= ~0b11000111; // PD: 7,6,2,1,0
 222     PORTD &= ~0b11000111;
 223     DDRF  &= ~0b11000000; // PF: 7,6
 224     PORTF &= ~0b11000000;
 225 }
 226
 227 inline
 228 static void select_row(uint8_t row)
 229 {
 230     // Output low(DDR:1, PORT:0) to select
 231     // row: 0    1    2    3    4    5    6    7    8
 232     // pin: PD0, PC7, PD7, PF6, PD6, PD1, PD2, PC6, PF7
 233     switch (row) {
 234         case 0:
 235             DDRD  |= (1<<0);
 236             PORTD &= ~(1<<0);
 237             break;
 238         case 1:
 239             DDRC  |= (1<<7);
 240             PORTC &= ~(1<<7);
 241             break;
 242         case 2:
 243             DDRD  |= (1<<7);
 244             PORTD &= ~(1<<7);
 245             break;
 246         case 3:
 247             DDRF  |= (1<<6);
 248             PORTF &= ~(1<<6);
 249             break;
 250         case 4:
 251             DDRD  |= (1<<6);
 252             PORTD &= ~(1<<6);
 253             break;
 254         case 5:
 255             DDRD  |= (1<<1);
 256             PORTD &= ~(1<<1);
 257             break;
 258         case 6:
 259             DDRD  |= (1<<2);
 260             PORTD &= ~(1<<2);
 261             break;
 262         case 7:
 263             DDRC  |= (1<<6);
 264             PORTC &= ~(1<<6);
 265             break;
 266         case 8:
 267             DDRF  |= (1<<7);
 268             PORTF &= ~(1<<7);
 269             break;
 270     }
 271 }