orphan/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 #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 #ifdef MATRIX_HAS_GHOST
  41 static bool matrix_has_ghost_in_row(uint8_t row);
  42 #endif
  43 static matrix_row_t read_cols(void);
  44 static void unselect_rows(void);
  45 static void select_row(uint8_t row);
  46
  47
  48 inline
  49 uint8_t matrix_rows(void)
  50 {
  51     return MATRIX_ROWS;
  52 }
  53
  54 inline
  55 uint8_t matrix_cols(void)
  56 {
  57     return MATRIX_COLS;
  58 }
  59
  60 void matrix_init(void)
  61 {
  62     // initialize row and col
  63     unselect_rows();
  64     // Input with pull-up(DDR:0, PORT:1)
  65     DDRB = 0x00;
  66     PORTB = 0xFF;
  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
  75 uint8_t matrix_scan(void)
  76 {
  77     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
  78         select_row(i);
  79         _delay_us(30);  // without this wait read unstable value.
  80         matrix_row_t cols = read_cols();
  81         if (matrix_debouncing[i] != cols) {
  82             matrix_debouncing[i] = cols;
  83             if (debouncing) {
  84                 debug("bounce!: "); debug_hex(debouncing); debug("\n");
  85             }
  86             debouncing = DEBOUNCE;
  87         }
  88         unselect_rows();
  89     }
  90
  91     if (debouncing) {
  92         if (--debouncing) {
  93             _delay_ms(1);
  94         } else {
  95             for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
  96                 matrix[i] = matrix_debouncing[i];
  97             }
  98         }
  99
 100     }
 101
 102     return 1;
 103 }
 104
 105 bool matrix_is_modified(void)
 106 {
 107     if (debouncing) return false;
 108     return true;
 109 }
 110
 111 inline
 112 bool matrix_is_on(uint8_t row, uint8_t col)
 113 {
 114     return (matrix[row] & ((matrix_row_t)1<<col));
 115 }
 116
 117 inline
 118 matrix_row_t matrix_get_row(uint8_t row)
 119 {
 120     return matrix[row];
 121 }
 122
 123 void matrix_print(void)
 124 {
 125     print("\nr/c 01234567\n");
 126     for (uint8_t row = 0; row < matrix_rows(); row++) {
 127         phex(row); print(": ");
 128         pbin_reverse(matrix_get_row(row));
 129 #ifdef MATRIX_HAS_GHOST
 130         if (matrix_has_ghost_in_row(row)) {
 131             print(" <ghost");
 132         }
 133 #endif
 134         print("\n");
 135     }
 136 }
 137
 138 #ifdef MATRIX_HAS_GHOST
 139 inline
 140 static bool matrix_has_ghost_in_row(uint8_t row)
 141 {
 142     // no ghost exists in case less than 2 keys on
 143     if (((matrix[row] - 1) & matrix[row]) == 0)
 144         return false;
 145
 146     // ghost exists in case same state as other row
 147     for (uint8_t i=0; i < MATRIX_ROWS; i++) {
 148         if (i != row && (matrix[i] & matrix[row]))
 149             return true;
 150     }
 151     return false;
 152 }
 153 #endif
 154
 155 inline
 156 static matrix_row_t read_cols(void)
 157 {
 158     return ~PINB;
 159 }
 160
 161 inline
 162 static void unselect_rows(void)
 163 {
 164     // Hi-Z(DDR:0, PORT:0) to unselect
 165     DDRC  &= ~0b01000000; // PC: 6
 166     PORTC &= ~0b01000000;
 167     DDRD  &= ~0b11100111; // PD: 7,6,5,2,1,0
 168     PORTD &= ~0b11100111;
 169     DDRF  &= ~0b11000000; // PF: 7,6
 170     PORTF &= ~0b11000000;
 171 }
 172
 173 inline
 174 static void select_row(uint8_t row)
 175 {
 176     // Output low(DDR:1, PORT:0) to select
 177     // row: 0    1    2    3    4    5    6    7    8
 178     // pin: PD0, PD5, PD7, PF6, PD6, PD1, PD2, PC6, PF7
 179     switch (row) {
 180         case 0:
 181             DDRD  |= (1<<0);
 182             PORTD &= ~(1<<0);
 183             break;
 184         case 1:
 185             DDRD  |= (1<<5);
 186             PORTD &= ~(1<<5);
 187             break;
 188         case 2:
 189             DDRD  |= (1<<7);
 190             PORTD &= ~(1<<7);
 191             break;
 192         case 3:
 193             DDRF  |= (1<<6);
 194             PORTF &= ~(1<<6);
 195             break;
 196         case 4:
 197             DDRD  |= (1<<6);
 198             PORTD &= ~(1<<6);
 199             break;
 200         case 5:
 201             DDRD  |= (1<<1);
 202             PORTD &= ~(1<<1);
 203             break;
 204         case 6:
 205             DDRD  |= (1<<2);
 206             PORTD &= ~(1<<2);
 207             break;
 208         case 7:
 209             DDRC  |= (1<<6);
 210             PORTC &= ~(1<<6);
 211             break;
 212         case 8:
 213             DDRF  |= (1<<7);
 214             PORTF &= ~(1<<7);
 215             break;
 216     }
 217 }