summaryrefslogtreecommitdiffstats
path: root/hhkb/matrix.c
blob: fefd24787379e0336947b59ea7a84a10df6a11d1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/*
 * scan matrix
 */
#include <stdint.h>
#include <stdbool.h>
#include <avr/io.h>
#include <util/delay.h>
#include "print.h"
#include "util.h"
#include "matrix.h"


#if (MATRIX_COLS > 16)
#   error "MATRIX_COLS must not exceed 16"
#endif
#if (MATRIX_ROWS > 255)
#   error "MATRIX_ROWS must not exceed 255"
#endif


// matrix state buffer(1:on, 0:off)
#if (MATRIX_COLS <= 8)
static uint8_t *matrix;
static uint8_t *matrix_prev;
static uint8_t _matrix0[MATRIX_ROWS];
static uint8_t _matrix1[MATRIX_ROWS];
#else
static uint16_t *matrix;
static uint16_t *matrix_prev;
static uint16_t _matrix0[MATRIX_ROWS];
static uint16_t _matrix1[MATRIX_ROWS];
#endif

#ifdef MATRIX_HAS_GHOST
static bool matrix_has_ghost_in_row(uint8_t row);
#endif


// matrix is active low. (key on: 0/key off: 1)
//
// HHKB has no ghost and no bounce.
// row: HC4051 select input channel(0-8)
//      PB0, PB1, PB2(A, B, C)
// col: LS145 select low output line(0-8)
//      PB3, PB4, PB5, PB6(A, B, C, D)
//      use D as ENABLE: (enable: 0/unenable: 1)
// key: KEY: (on: 0/ off:1)
//      KEY_PREV: (on: 1/ off: 0)
//      PE6,PE7(KEY, KEY_PREV)
#define COL_ENABLE              (1<<6)
#define KEY_SELELCT(ROW, COL)   (PORTB = (PORTB&(1<<7))|COL_ENABLE|(((COL)&0x07)<<3)|((ROW)&0x07))
#define KEY_ENABLE              (PORTB &= ~COL_ENABLE)
#define KEY_UNABLE              (PORTB |=  COL_ENABLE)
#define KEY_STATE               (PINE&(1<<6))
#define KEY_PREV_ON             (PORTE |= (1<<7))
#define KEY_PREV_OFF            (PORTE &= ~(1<<7))


inline
uint8_t matrix_rows(void)
{
    return MATRIX_ROWS;
}

inline
uint8_t matrix_cols(void)
{
    return MATRIX_COLS;
}

void matrix_init(void)
{
    // row & col output(PB0-6)
    DDRB = 0xFF;
    KEY_SELELCT(0, 0);
    // KEY: input with pullup(PE6)
    // KEY_PREV: output(PE7)
    DDRE = 0xBF;
    PORTE = 0x40;

    // initialize matrix state: all keys off
    for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0x00;
    for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0x00;
    matrix = _matrix0;
    matrix_prev = _matrix1;
}

uint8_t matrix_scan(void)
{
    uint8_t *tmp;

    tmp = matrix_prev;
    matrix_prev = matrix;
    matrix = tmp;

    for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
        for (uint8_t col = 0; col < MATRIX_COLS; col++) {
            KEY_SELELCT(row, col);
            _delay_us(40);  // from logic analyzer chart
            if (matrix_prev[row] & (1<<col)) {
                KEY_PREV_ON;
            }
            _delay_us(7);  // from logic analyzer chart
            KEY_ENABLE;
            _delay_us(10);  // from logic analyzer chart
            if (KEY_STATE) {
                matrix[row] &= ~(1<<col);
            } else {
                matrix[row] |= (1<<col);
            }
            KEY_PREV_OFF;
            KEY_UNABLE;
            _delay_us(150);  // from logic analyzer chart
        }
    }
    return 1;
}

bool matrix_is_modified(void)
{
    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
        if (matrix[i] != matrix_prev[i])
            return true;
    }
    return false;
}

inline
bool matrix_has_ghost(void)
{
#ifdef MATRIX_HAS_GHOST
    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
        if (matrix_has_ghost_in_row(i))
            return true;
    }
#endif
    return false;
}

inline
bool matrix_is_on(uint8_t row, uint8_t col)
{
    return (matrix[row] & (1<<col));
}

inline
#if (MATRIX_COLS <= 8)
uint8_t matrix_get_row(uint8_t row)
#else
uint16_t matrix_get_row(uint8_t row)
#endif
{
    return matrix[row];
}

void matrix_print(void)
{
#if (MATRIX_COLS <= 8)
    print("\nr/c 01234567\n");
#else
    print("\nr/c 0123456789ABCDEF\n");
#endif
    for (uint8_t row = 0; row < matrix_rows(); row++) {
        phex(row); print(": ");
#if (MATRIX_COLS <= 8)
        pbin_reverse(matrix_get_row(row));
#else
        pbin_reverse16(matrix_get_row(row));
#endif
#ifdef MATRIX_HAS_GHOST
        if (matrix_has_ghost_in_row(row)) {
            print(" <ghost");
        }
#endif
        print("\n");
    }
}

uint8_t matrix_key_count(void)
{
    uint8_t count = 0;
    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
#if (MATRIX_COLS <= 8)
        count += bitpop(matrix[i]);
#else
        count += bitpop16(matrix[i]);
#endif
    }
    return count;
}

#ifdef MATRIX_HAS_GHOST
inline
static bool matrix_has_ghost_in_row(uint8_t row)
{
    // no ghost exists in case less than 2 keys on
    if (((matrix[row] - 1) & matrix[row]) == 0)
        return false;

    // ghost exists in case same state as other row
    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
        if (i != row && (matrix[i] & matrix[row]) == matrix[row])
            return true;
    }
    return false;
}
#endif