matrix.c (9091B)
1 /* 2 Copyright 2013 Oleg Kostyuk <cub.uanic@gmail.com> 3 2020 Pierre Chevalier <pierrechevalier83@gmail.com> 4 2021 weteor 5 6 This program is free software: you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation, either version 2 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 /* 21 * This code was heavily inspired by the ergodox_ez keymap, and modernized 22 * to take advantage of the quantum.h microcontroller agnostics gpio control 23 * abstractions and use the macros defined in config.h for the wiring as opposed 24 * to repeating that information all over the place. 25 */ 26 27 #include "matrix.h" 28 #include "debug.h" 29 #include "wait.h" 30 #include "i2c_master.h" 31 32 extern i2c_status_t tca9555_status; 33 #define I2C_TIMEOUT 1000 34 35 // I2C address: 36 // All address pins of the tca9555 are connected to the ground 37 // | 0 | 1 | 0 | 0 | A2 | A1 | A0 | 38 // | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 39 #define I2C_ADDR (0b0100000 << 1) 40 41 // Register addresses 42 #define IODIRA 0x06 // i/o direction register 43 #define IODIRB 0x07 44 #define IREGP0 0x00 // GPIO pull-up resistor register 45 #define IREGP1 0x01 46 #define OREGP0 0x02 // general purpose i/o port register (write modifies OLAT) 47 #define OREGP1 0x03 48 49 bool i2c_initialized = 0; 50 i2c_status_t tca9555_status = I2C_ADDR; 51 52 uint8_t init_tca9555(void) { 53 print("starting init"); 54 tca9555_status = I2C_ADDR; 55 56 // I2C subsystem 57 if (i2c_initialized == 0) { 58 i2c_init(); // on pins D(1,0) 59 i2c_initialized = true; 60 wait_ms(I2C_TIMEOUT); 61 } 62 63 // set pin direction 64 // - unused : input : 1 65 // - input : input : 1 66 // - driving : output : 0 67 uint8_t conf[2] = { 68 // This means: read all pins of port 0 69 0b11111111, 70 // This means: we will write on pins 0 to 3 on port 1. read rest 71 0b11110000, 72 }; 73 tca9555_status = i2c_write_register(I2C_ADDR, IODIRA, conf, 2, I2C_TIMEOUT); 74 75 return tca9555_status; 76 } 77 78 /* matrix state(1:on, 0:off) */ 79 static matrix_row_t matrix[MATRIX_ROWS]; // debounced values 80 81 static matrix_row_t read_cols(uint8_t row); 82 static void init_cols(void); 83 static void unselect_rows(void); 84 static void select_row(uint8_t row); 85 86 static uint8_t tca9555_reset_loop; 87 88 void matrix_init_custom(void) { 89 // initialize row and col 90 91 tca9555_status = init_tca9555(); 92 93 unselect_rows(); 94 init_cols(); 95 96 // initialize matrix state: all keys off 97 for (uint8_t i = 0; i < MATRIX_ROWS; i++) { 98 matrix[i] = 0; 99 } 100 } 101 102 void matrix_power_up(void) { 103 tca9555_status = init_tca9555(); 104 105 unselect_rows(); 106 init_cols(); 107 108 // initialize matrix state: all keys off 109 for (uint8_t i = 0; i < MATRIX_ROWS; i++) { 110 matrix[i] = 0; 111 } 112 } 113 114 // Reads and stores a row, returning 115 // whether a change occurred. 116 static inline bool store_matrix_row(matrix_row_t current_matrix[], uint8_t index) { 117 matrix_row_t temp = read_cols(index); 118 if (current_matrix[index] != temp) { 119 current_matrix[index] = temp; 120 return true; 121 } 122 return false; 123 } 124 125 bool matrix_scan_custom(matrix_row_t current_matrix[]) { 126 if (tca9555_status) { // if there was an error 127 if (++tca9555_reset_loop == 0) { 128 // since tca9555_reset_loop is 8 bit - we'll try to reset once in 255 matrix scans 129 // this will be approx bit more frequent than once per second 130 dprint("trying to reset tca9555\n"); 131 tca9555_status = init_tca9555(); 132 if (tca9555_status) { 133 dprint("right side not responding\n"); 134 } else { 135 dprint("right side attached\n"); 136 } 137 } 138 } 139 140 bool changed = false; 141 for (uint8_t i = 0; i < MATRIX_ROWS_PER_SIDE; i++) { 142 // select rows from left and right hands 143 uint8_t left_index = i; 144 uint8_t right_index = i + MATRIX_ROWS_PER_SIDE; 145 select_row(left_index); 146 select_row(right_index); 147 148 // we don't need a 30us delay anymore, because selecting a 149 // left-hand row requires more than 30us for i2c. 150 151 changed |= store_matrix_row(current_matrix, left_index); 152 changed |= store_matrix_row(current_matrix, right_index); 153 154 unselect_rows(); 155 } 156 157 return changed; 158 } 159 160 static void init_cols(void) { 161 // init on tca9555 162 // not needed, already done as part of init_tca9555() 163 164 // init on mcu 165 pin_t matrix_col_pins_mcu[MATRIX_COLS_PER_SIDE] = MATRIX_COL_PINS_L; 166 for (int pin_index = 0; pin_index < MATRIX_COLS_PER_SIDE; pin_index++) { 167 pin_t pin = matrix_col_pins_mcu[pin_index]; 168 gpio_set_pin_input(pin); 169 gpio_write_pin_high(pin); 170 } 171 } 172 173 static matrix_row_t read_cols(uint8_t row) { 174 if (row < MATRIX_ROWS_PER_SIDE) { 175 pin_t matrix_col_pins_mcu[MATRIX_COLS_PER_SIDE] = MATRIX_COL_PINS_L; 176 matrix_row_t current_row_value = 0; 177 // For each col... 178 for (uint8_t col_index = 0; col_index < MATRIX_COLS_PER_SIDE; col_index++) { 179 // Select the col pin to read (active low) 180 uint8_t pin_state = gpio_read_pin(matrix_col_pins_mcu[col_index]); 181 182 // Populate the matrix row with the state of the col pin 183 current_row_value |= pin_state ? 0 : (MATRIX_ROW_SHIFTER << col_index); 184 } 185 return current_row_value; 186 } else { 187 if (tca9555_status) { // if there was an error 188 return 0; 189 } else { 190 uint8_t data = 0; 191 uint8_t port0 = 0; 192 tca9555_status = i2c_read_register(I2C_ADDR, IREGP0, &port0, 1, I2C_TIMEOUT); 193 if (tca9555_status) { // if there was an error 194 // do nothing 195 return 0; 196 } else { 197 port0 = ~port0; 198 // We read all the pins on GPIOA. 199 // The initial state was all ones and any depressed key at a given column for the currently selected row will have its bit flipped to zero. 200 // The return value is a row as represented in the generic matrix code were the rightmost bits represent the lower columns and zeroes represent non-depressed keys while ones represent depressed keys. 201 // the pins connected to eact columns are sequential, but in reverse order, and counting from zero down (col 5 -> GPIO04, col6 -> GPIO03 and so on). 202 data |= (port0 & 0x01) << 4; 203 data |= (port0 & 0x02) << 2; 204 data |= (port0 & 0x04); 205 data |= (port0 & 0x08) >> 2; 206 data |= (port0 & 0x10) >> 4; 207 208 tca9555_status = I2C_STATUS_SUCCESS; 209 return data; 210 } 211 } 212 } 213 } 214 215 static void unselect_rows(void) { 216 // no need to unselect on tca9555, because the select step sets all 217 // the other row bits high, and it's not changing to a different 218 // direction 219 220 // unselect rows on microcontroller 221 pin_t matrix_row_pins_mcu[MATRIX_ROWS_PER_SIDE] = MATRIX_ROW_PINS_L; 222 for (int pin_index = 0; pin_index < MATRIX_ROWS_PER_SIDE; pin_index++) { 223 pin_t pin = matrix_row_pins_mcu[pin_index]; 224 gpio_set_pin_input(pin); 225 gpio_write_pin_low(pin); 226 } 227 } 228 229 static void select_row(uint8_t row) { 230 uint8_t port1 = 0xff; 231 232 if (row < MATRIX_ROWS_PER_SIDE) { 233 // select on atmega32u4 234 pin_t matrix_row_pins_mcu[MATRIX_ROWS_PER_SIDE] = MATRIX_ROW_PINS_L; 235 pin_t pin = matrix_row_pins_mcu[row]; 236 gpio_set_pin_output(pin); 237 gpio_write_pin_low(pin); 238 } else { 239 // select on tca9555 240 if (tca9555_status) { // if there was an error 241 // do nothing 242 } else { 243 switch(row) { 244 case 4: port1 &= ~(1 << 0); break; 245 case 5: port1 &= ~(1 << 1); break; 246 case 6: port1 &= ~(1 << 2); break; 247 case 7: 248 port1 &= ~(1 << 3); 249 break; 250 default: break; 251 } 252 253 tca9555_status = i2c_write_register(I2C_ADDR, OREGP1, &port1, 1, I2C_TIMEOUT); 254 // Select the desired row by writing a byte for the entire GPIOB bus where only the bit representing the row we want to select is a zero (write instruction) and every other bit is a one. 255 // Note that the row - MATRIX_ROWS_PER_SIDE reflects the fact that being on the right hand, the columns are numbered from MATRIX_ROWS_PER_SIDE to MATRIX_ROWS, but the pins we want to write to are indexed from zero up on the GPIOB bus. 256 } 257 } 258 }