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qmk_firmware

custom branch of QMK firmware git clone https://anongit.hacktivis.me/git/qmk_firmware.git

matrix.c (3775B)

    

  1. /*
  2.   Copyright (c) 2022 David Kuehling <dvdkhlng TA posteo TOD de>
  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.
  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.
  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. */
  18. #include "spi_master.h"
  19. #include "matrix.h"
  21. static pin_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
  23. static void unselect_rows(void);
  25. void matrix_init_custom(void) {
  26.     /* initialize row pins */
  27.     for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
  28.         gpio_set_pin_output(row_pins[row]);
  29.     }
  30.     unselect_rows();
  32.     /* columns read via shift-register on SPI lines */
  34.     /* Enable SPI, Master, set clock rate fck/16.  First bit already at Qh
  35.      * output before clock edge (CPHA=0).  SN74HC165 shift register shifts
  36.      * on low-to-high transition (CPOL=1).  Receive the LSB first (DORD=1).
  37.      */
  38.     bool lsbFirst = true;
  39.     uint8_t mode = 2;  /* CPOL=1, CPHA=0 */
  40.     uint16_t divisor = 16;
  42.     /* According to Atmega32U4 datasheet, PB0 *must* be set to output,
  43.      * otherwise it will interfere with SPI master operation.  On pro-micro
  44.      * it's connected to a yellew LED. */
  45.     pin_t slavePin = PB0;
  46.     spi_init();
  47.     spi_start(slavePin, lsbFirst, mode, divisor);
  49.     /* Initialize pin controlling the shift register's SH/~LD pin */
  50.     gpio_set_pin_output(ROW_SHIFT_PIN);
  51. }
  53. static void select_row(uint8_t row) {
  54.     pin_t pin = row_pins[row];
  55.     if (pin != NO_PIN) {
  56.         gpio_write_pin_high(pin);
  57.     }
  58. }
  60. static void unselect_row(uint8_t row) {
  61.     pin_t pin = row_pins[row];
  62.     if (pin != NO_PIN) {
  63.         gpio_write_pin_low(pin);
  64.     }
  65. }
  67. static void unselect_rows(void) {
  68.     for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
  69.         unselect_row(row);
  70.     }
  71. }
  73. bool matrix_read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
  74.     /* Start with a clear matrix row */
  75.     matrix_row_t current_row_value = 0;
  77.     /* Set shift register SH/~LD pin to "load" mode */
  78.     gpio_write_pin_low(ROW_SHIFT_PIN);
  79.     select_row(current_row);
  80.     matrix_output_select_delay();
  82.     /* Set shift register SH/~LD pin to "shift" mode */
  83.     gpio_write_pin_high(ROW_SHIFT_PIN);
  85.     /* For each octet of columns... */
  86.     for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index += 8) {
  87.         spi_status_t read_result = spi_read();
  88.         if (read_result >= 0) {
  89.             /* only if SPI read successful: populate the matrix row with the
  90.                state of the 8 consecutive column bits */
  91.             current_row_value |= ((matrix_row_t)read_result << col_index);
  92.         }
  93.     }
  95.     /* Unselect row & wait for all columns signals to go high. */
  96.     unselect_row(current_row);
  97.     matrix_output_unselect_delay(current_row, current_row_value != 0); 
  99.     /* Update row in matrix. */
  100.     if (current_row_value != current_matrix[current_row]) {
  101.         current_matrix[current_row] = current_row_value;
  102.         return true;
  103.     }
  105.     return false;
  106. }
  108. bool matrix_scan_custom(matrix_row_t curr_matrix[]) {
  109.     bool changed = false;
  111.     /* set row, read cols */
  112.     for (uint8_t current_row = 0; current_row < MATRIX_ROWS; current_row++) {
  113.         changed |= matrix_read_cols_on_row(curr_matrix, current_row);
  114.     }
  116.     return changed;
  117. }
  119. /*
  120.  * Local Variables:
  121.  * c-basic-offset:4
  122.  * fill-column: 76
  123.  * End:
  124.  */