keyboard/phantom/matrix.c

   1 /* Copyright 2012 Jun Wako <wakojun@gmail.com>
   2  *
   3  * This is heavily based on phantom/board.{c|h}.
   4  * https://github.com/BathroomEpiphanies/AVR-Keyboard
   5  *
   6  * Copyright (c) 2012 Fredrik Atmer, Bathroom Epiphanies Inc
   7  * http://bathroomepiphanies.com
   8  *
   9  * As for liscensing consult with the original files or its author.
  10  */
  11 #include <stdint.h>
  12 #include <stdbool.h>
  13 #include <avr/io.h>
  14 #include <util/delay.h>
  15 #include "print.h"
  16 #include "debug.h"
  17 #include "util.h"
  18 #include "matrix.h"
  19
  20
  21 #ifndef DEBOUNCE
  22 #   define DEBOUNCE     0
  23 #endif
  24 static uint8_t debouncing = DEBOUNCE;
  25
  26 // bit array of key state(1:on, 0:off)
  27 static matrix_row_t matrix[MATRIX_ROWS];
  28 static matrix_row_t matrix_debouncing[MATRIX_ROWS];
  29
  30
  31 #define _DDRA (uint8_t *const)&DDRA
  32 #define _DDRB (uint8_t *const)&DDRB
  33 #define _DDRC (uint8_t *const)&DDRC
  34 #define _DDRD (uint8_t *const)&DDRD
  35 #define _DDRE (uint8_t *const)&DDRE
  36 #define _DDRF (uint8_t *const)&DDRF
  37
  38 #define _PINA (uint8_t *const)&PINA
  39 #define _PINB (uint8_t *const)&PINB
  40 #define _PINC (uint8_t *const)&PINC
  41 #define _PIND (uint8_t *const)&PIND
  42 #define _PINE (uint8_t *const)&PINE
  43 #define _PINF (uint8_t *const)&PINF
  44
  45 #define _PORTA (uint8_t *const)&PORTA
  46 #define _PORTB (uint8_t *const)&PORTB
  47 #define _PORTC (uint8_t *const)&PORTC
  48 #define _PORTD (uint8_t *const)&PORTD
  49 #define _PORTE (uint8_t *const)&PORTE
  50 #define _PORTF (uint8_t *const)&PORTF
  51
  52 #define _BIT0 0x01
  53 #define _BIT1 0x02
  54 #define _BIT2 0x04
  55 #define _BIT3 0x08
  56 #define _BIT4 0x10
  57 #define _BIT5 0x20
  58 #define _BIT6 0x40
  59 #define _BIT7 0x80
  60
  61 /* Specifies the ports and pin numbers for the rows */
  62 static
  63 uint8_t *const row_ddr[MATRIX_ROWS] = {_DDRB,  _DDRB,  _DDRB,  _DDRB,  _DDRB,  _DDRB};
  64
  65 static
  66 uint8_t *const row_port[MATRIX_ROWS] = {_PORTB, _PORTB, _PORTB, _PORTB, _PORTB, _PORTB};
  67
  68 static
  69 uint8_t *const row_pin[MATRIX_ROWS] = {_PINB,  _PINB,  _PINB,  _PINB,  _PINB,  _PINB};
  70
  71 static
  72 const uint8_t row_bit[MATRIX_ROWS] = { _BIT0,  _BIT1,  _BIT2,  _BIT3,  _BIT4,  _BIT5};
  73
  74 /* Specifies the ports and pin numbers for the columns */
  75 static
  76 uint8_t *const  col_ddr[MATRIX_COLS] = { _DDRD,  _DDRC,  _DDRC,  _DDRD,  _DDRD,  _DDRE,
  77                                   _DDRF,  _DDRF,  _DDRF,  _DDRF,  _DDRF,  _DDRF,
  78                                   _DDRD,  _DDRD,  _DDRD,  _DDRD,  _DDRD};
  79
  80 static
  81 uint8_t *const col_port[MATRIX_COLS] = {_PORTD, _PORTC, _PORTC, _PORTD, _PORTD, _PORTE,
  82                                  _PORTF, _PORTF, _PORTF, _PORTF, _PORTF, _PORTF,
  83                                  _PORTD, _PORTD, _PORTD, _PORTD, _PORTD};
  84
  85 static
  86 const uint8_t   col_bit[MATRIX_COLS] = {  _BIT5,  _BIT7,  _BIT6,  _BIT4,  _BIT0,  _BIT6,
  87                                   _BIT0,  _BIT1,  _BIT4,  _BIT5,  _BIT6,  _BIT7,
  88                                   _BIT7,  _BIT6,  _BIT1,  _BIT2,  _BIT3};
  89
  90 static
  91 inline void pull_column(int col) {
  92   *col_port[col] &= ~col_bit[col];
  93 }
  94
  95 static
  96 inline void release_column(int col) {
  97   *col_port[col] |=  col_bit[col];
  98 }
  99
 100 /* PORTB is set as input with pull-up resistors
 101    PORTC,D,E,F are set to high output */
 102
 103 static
 104 void setup_io_pins(void) {
 105   uint8_t row, col;
 106   for(row = 0; row < MATRIX_ROWS; row++) {
 107     *row_ddr[row]  &= ~row_bit[row];
 108     *row_port[row] |=  row_bit[row];
 109   }
 110   for(col = 0; col < MATRIX_COLS; col++) {
 111     *col_ddr[col]  |= col_bit[col];
 112     *col_port[col] |= col_bit[col];
 113   }
 114 }
 115
 116 /* LEDs are on output compare pins OC1B OC1C
 117    This activates fast PWM mode on them.
 118    Prescaler 256 and 8-bit counter results in
 119    16000000/256/256 = 244 Hz blink frequency.
 120    LED_A: Caps Lock
 121    LED_B: Scroll Lock  */
 122 /* Output on PWM pins are turned off when the timer
 123    reaches the value in the output compare register,
 124    and are turned on when it reaches TOP (=256). */
 125 static
 126 void setup_leds(void) {
 127   TCCR1A |=      // Timer control register 1A
 128     (1<<WGM10) | // Fast PWM 8-bit
 129     (1<<COM1B1)| // Clear OC1B on match, set at TOP
 130     (1<<COM1C1); // Clear OC1C on match, set at TOP
 131   TCCR1B |=      // Timer control register 1B
 132     (1<<WGM12) | // Fast PWM 8-bit
 133     (1<<CS12);   // Prescaler 256
 134   OCR1B = 250;    // Output compare register 1B
 135   OCR1C = 250;    // Output compare register 1C
 136   // LEDs: LED_A -> PORTB6, LED_B -> PORTB7
 137   DDRB  &= 0x3F;
 138   PORTB &= 0x3F;
 139 }
 140
 141
 142 inline
 143 uint8_t matrix_rows(void)
 144 {
 145     return MATRIX_ROWS;
 146 }
 147
 148 inline
 149 uint8_t matrix_cols(void)
 150 {
 151     return MATRIX_COLS;
 152 }
 153
 154 void matrix_init(void)
 155 {
 156     // To use PORTF disable JTAG with writing JTD bit twice within four cycles.
 157     MCUCR |= (1<<JTD);
 158     MCUCR |= (1<<JTD);
 159
 160     // initialize row and col
 161     setup_io_pins();
 162     setup_leds();
 163
 164     // initialize matrix state: all keys off
 165     for (uint8_t i=0; i < MATRIX_ROWS; i++)  {
 166         matrix[i] = 0;
 167         matrix_debouncing[i] = 0;
 168     }
 169 }
 170
 171 uint8_t matrix_scan(void)
 172 {
 173     for (uint8_t col = 0; col < MATRIX_COLS; col++) {  // 0-16
 174         pull_column(col);   // output hi on theline
 175         _delay_us(3);       // without this wait it won't read stable value.
 176         for (uint8_t row = 0; row < MATRIX_ROWS; row++) {  // 0-5
 177             bool prev_bit = matrix_debouncing[row] & ((matrix_row_t)1<<col);
 178             bool curr_bit = !(*row_pin[row] & row_bit[row]);
 179             if (prev_bit != curr_bit) {
 180                 matrix_debouncing[row] ^= ((matrix_row_t)1<<col);
 181                 if (debouncing) {
 182                     debug("bounce!: "); debug_hex(debouncing); print("\n");
 183                 }
 184                 debouncing = DEBOUNCE;
 185             }
 186         }
 187         release_column(col);
 188     }
 189
 190     if (debouncing) {
 191         if (--debouncing) {
 192             _delay_ms(1);
 193         } else {
 194             for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 195                 matrix[i] = matrix_debouncing[i];
 196             }
 197         }
 198     }
 199
 200     return 1;
 201 }
 202
 203 bool matrix_is_modified(void)
 204 {
 205     // NOTE: no longer used
 206     return true;
 207 }
 208
 209 inline
 210 bool matrix_is_on(uint8_t row, uint8_t col)
 211 {
 212     return (matrix[row] & ((matrix_row_t)1<<col));
 213 }
 214
 215 inline
 216 matrix_row_t matrix_get_row(uint8_t row)
 217 {
 218     return matrix[row];
 219 }
 220
 221 void matrix_print(void)
 222 {
 223     print("\nr/c 01234567\n");
 224     for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
 225         phex(row); print(": ");
 226         pbin_reverse(matrix_get_row(row));
 227         print("\n");
 228     }
 229 }
 230
 231 uint8_t matrix_key_count(void)
 232 {
 233     uint8_t count = 0;
 234     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
 235         for (uint8_t j = 0; j < MATRIX_COLS; j++) {
 236             if (matrix_is_on(i, j))
 237                 count++;
 238         }
 239     }
 240     return count;
 241 }