keyboard/hhkb/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 <avr/interrupt.h>
  25 #include <util/delay.h>
  26 #include "print.h"
  27 #include "debug.h"
  28 #include "util.h"
  29 #include "timer.h"
  30 #include "matrix.h"
  31
  32
  33 // Timer resolution check
  34 #if (1000000/TIMER_RAW_FREQ > 20)
  35 #   error "Timer resolution(>20us) is not enough for HHKB matrix scan tweak on V-USB."
  36 #endif
  37
  38 #if (MATRIX_COLS > 16)
  39 #   error "MATRIX_COLS must not exceed 16"
  40 #endif
  41 #if (MATRIX_ROWS > 255)
  42 #   error "MATRIX_ROWS must not exceed 255"
  43 #endif
  44
  45
  46 // matrix state buffer(1:on, 0:off)
  47 static matrix_row_t *matrix;
  48 static matrix_row_t *matrix_prev;
  49 static matrix_row_t _matrix0[MATRIX_ROWS];
  50 static matrix_row_t _matrix1[MATRIX_ROWS];
  51
  52
  53 // Matrix I/O ports
  54 //
  55 // row:     HC4051[A,B,C]  selects scan row0-7
  56 // col:     LS145[A,B,C,D] selects scan col0-7 and enable(D)
  57 // key:     on: 0/off: 1
  58 // prev:    unknown: output previous key state(negated)?
  59
  60 #if defined(__AVR_AT90USB1286__)
  61 // Ports for Teensy++
  62 // row:     PB0-2
  63 // col:     PB3-5,6
  64 // key:     PE6(pull-uped)
  65 // prev:    PE7
  66 #define KEY_INIT()              do {    \
  67     DDRB |= 0x7F;                       \
  68     DDRE |=  (1<<7);                    \
  69     DDRE &= ~(1<<6);                    \
  70     PORTE |= (1<<6);                    \
  71 } while (0)
  72 #define KEY_SELECT(ROW, COL)    (PORTB = (PORTB & 0xC0) |       \
  73                                          (((COL) & 0x07)<<3) |    \
  74                                          ((ROW) & 0x07))
  75 #define KEY_ENABLE()            (PORTB &= ~(1<<6))
  76 #define KEY_UNABLE()            (PORTB |=  (1<<6))
  77 #define KEY_STATE()             (PINE & (1<<6))
  78 #define KEY_PREV_ON()           (PORTE |=  (1<<7))
  79 #define KEY_PREV_OFF()          (PORTE &= ~(1<<7))
  80 #define KEY_POWER_ON()
  81 #define KEY_POWER_OFF()
  82
  83 #elif defined(__AVR_ATmega328P__)
  84 // Ports for V-USB
  85 // key:     PB0(pull-uped)
  86 // prev:    PB1
  87 // row:     PB2-4
  88 // col:     PC0-2,3
  89 // power:   PB5(Low:on/Hi-z:off)
  90 #define KEY_INIT()              do {    \
  91     DDRB  |= 0x3E;                      \
  92     DDRB  &= ~(1<<0);                   \
  93     PORTB |= 1<<0;                      \
  94     DDRC  |= 0x0F;                      \
  95     KEY_UNABLE();                       \
  96     KEY_PREV_OFF();                     \
  97 } while (0)
  98 #define KEY_SELECT(ROW, COL)    do {    \
  99     PORTB = (PORTB & 0xE3) | ((ROW) & 0x07)<<2; \
 100     PORTC = (PORTC & 0xF8) | ((COL) & 0x07);    \
 101 } while (0)
 102 #define KEY_ENABLE()            (PORTC &= ~(1<<3))
 103 #define KEY_UNABLE()            (PORTC |=  (1<<3))
 104 #define KEY_STATE()             (PINB & (1<<0))
 105 #define KEY_PREV_ON()           (PORTB |=  (1<<1))
 106 #define KEY_PREV_OFF()          (PORTB &= ~(1<<1))
 107 // Power supply switching
 108 #define KEY_POWER_ON()          do {    \
 109     KEY_INIT();                         \
 110     PORTB &= ~(1<<5);                   \
 111     _delay_ms(1);                       \
 112 } while (0)
 113 #define KEY_POWER_OFF()         do {    \
 114     DDRB  &= ~0x3F;                     \
 115     PORTB &= ~0x3F;                     \
 116     DDRC  &= ~0x0F;                     \
 117     PORTC &= ~0x0F;                     \
 118 } while (0)
 119
 120 #else
 121 #   error "define code for matrix scan"
 122 #endif
 123
 124
 125 inline
 126 uint8_t matrix_rows(void)
 127 {
 128     return MATRIX_ROWS;
 129 }
 130
 131 inline
 132 uint8_t matrix_cols(void)
 133 {
 134     return MATRIX_COLS;
 135 }
 136
 137 void matrix_init(void)
 138 {
 139 #ifdef DEBUG
 140     print_enable = true;
 141     debug_enable = true;
 142     debug_keyboard = true;
 143 #endif
 144
 145     KEY_INIT();
 146
 147     // initialize matrix state: all keys off
 148     for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0x00;
 149     for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0x00;
 150     matrix = _matrix0;
 151     matrix_prev = _matrix1;
 152 }
 153
 154 uint8_t matrix_scan(void)
 155 {
 156     uint8_t *tmp;
 157
 158     tmp = matrix_prev;
 159     matrix_prev = matrix;
 160     matrix = tmp;
 161
 162     KEY_POWER_ON();
 163     for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
 164         for (uint8_t col = 0; col < MATRIX_COLS; col++) {
 165             KEY_SELECT(row, col);
 166             _delay_us(40);
 167
 168             // Not sure this is needed. This just emulates HHKB controller's behaviour.
 169             if (matrix_prev[row] & (1<<col)) {
 170                 KEY_PREV_ON();
 171             }
 172             _delay_us(7);
 173
 174             // NOTE: KEY_STATE is valid only in 20us after KEY_ENABLE.
 175             // If V-USB interrupts in this section we could lose 40us or so
 176             // and would read invalid value from KEY_STATE.
 177             uint8_t last = TIMER_RAW;
 178
 179             KEY_ENABLE();
 180             // Wait for KEY_STATE outputs its value.
 181             // 1us was ok on one HHKB, but not worked on another.
 182             _delay_us(10);
 183             if (KEY_STATE()) {
 184                 matrix[row] &= ~(1<<col);
 185             } else {
 186                 matrix[row] |= (1<<col);
 187             }
 188
 189             // Ignore if this code region execution time elapses more than 20us.
 190             // MEMO: 20[us] * (TIMER_RAW_FREQ / 1000000)[count per us]
 191             // MEMO: then change above using this rule: a/(b/c) = a*1/(b/c) = a*(c/b)
 192             if (TIMER_DIFF_RAW(TIMER_RAW, last) > 20/(1000000/TIMER_RAW_FREQ)) {
 193                 matrix[row] = matrix_prev[row];
 194             }
 195
 196             KEY_PREV_OFF();
 197             KEY_UNABLE();
 198             // NOTE: KEY_STATE keep its state in 20us after KEY_ENABLE.
 199             // This takes 25us or more to make sure KEY_STATE returns to idle state.
 200             _delay_us(150);
 201         }
 202     }
 203     KEY_POWER_OFF();
 204     return 1;
 205 }
 206
 207 bool matrix_is_modified(void)
 208 {
 209     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 210         if (matrix[i] != matrix_prev[i])
 211             return true;
 212     }
 213     return false;
 214 }
 215
 216 inline
 217 bool matrix_has_ghost(void)
 218 {
 219     return false;
 220 }
 221
 222 inline
 223 bool matrix_is_on(uint8_t row, uint8_t col)
 224 {
 225     return (matrix[row] & (1<<col));
 226 }
 227
 228 inline
 229 #if (MATRIX_COLS <= 8)
 230 uint8_t matrix_get_row(uint8_t row)
 231 #else
 232 uint16_t matrix_get_row(uint8_t row)
 233 #endif
 234 {
 235     return matrix[row];
 236 }
 237
 238 void matrix_print(void)
 239 {
 240 #if (MATRIX_COLS <= 8)
 241     print("\nr/c 01234567\n");
 242 #else
 243     print("\nr/c 0123456789ABCDEF\n");
 244 #endif
 245     for (uint8_t row = 0; row < matrix_rows(); row++) {
 246         phex(row); print(": ");
 247 #if (MATRIX_COLS <= 8)
 248         pbin_reverse(matrix_get_row(row));
 249 #else
 250         pbin_reverse16(matrix_get_row(row));
 251 #endif
 252         print("\n");
 253     }
 254 }
 255
 256 uint8_t matrix_key_count(void)
 257 {
 258     uint8_t count = 0;
 259     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 260 #if (MATRIX_COLS <= 8)
 261         count += bitpop(matrix[i]);
 262 #else
 263         count += bitpop16(matrix[i]);
 264 #endif
 265     }
 266     return count;
 267 }