qmk_firmware

ec.c (5323B)

---

 /* Copyright 2023 Viktus Design LLC
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include "ec.h"
 #include <avr/interrupt.h>
 
 #include "analog.h"
 //#include "debug.h"
 
 // sensing channel definitions
 #define A0 0
 #define A1 1
 #define A2 2
 #define A3 3
 #define A4 4
 #define A5 5
 #define A6 6
 #define A7 7
 
 // analog connection settings
 #define DISCHARGE_PIN D3
 #define ANALOG_PORT D4
 
 #ifndef MUX_SEL_PIN
 #    define MUX_SEL_PINS \
         { D0, D1, D2 }
 #endif
 
 // pin connections
 const uint8_t row_channels[] = MATRIX_ROW_PINS;
 const uint8_t col_pins[]     = MATRIX_COL_PINS;
 const uint8_t mux_sel_pins[] = MUX_SEL_PINS;
 
 _Static_assert(sizeof(mux_sel_pins) == 3, "invalid MUX_SEL_PINS");
 
 static ec_config_t config;
 static uint16_t    ec_sw_value[MATRIX_COLS][MATRIX_ROWS];
 
 static inline void discharge_capacitor(void) { gpio_set_pin_output(DISCHARGE_PIN); }
 static inline void charge_capacitor(uint8_t col) {
     gpio_set_pin_input(DISCHARGE_PIN);
     gpio_write_pin_high(col_pins[col]);
 }
 
 static inline void clear_all_col_pins(void) {
     for (int col = 0; col < sizeof(col_pins); col++) {
         gpio_write_pin_low(col_pins[col]);
     }
 }
 
 void init_mux_sel(void) {
     for (int idx = 0; idx < sizeof(mux_sel_pins); idx++) {
         gpio_set_pin_output(mux_sel_pins[idx]);
     }
 }
 
 void select_mux(uint8_t row) {
     uint8_t ch = row_channels[row];
     gpio_write_pin(mux_sel_pins[0], ch & 1);
     gpio_write_pin(mux_sel_pins[1], ch & 2);
     gpio_write_pin(mux_sel_pins[2], ch & 4);
 }
 
 void init_col(void) {
     for (int idx = 0; idx < sizeof(col_pins); idx++) {
         gpio_set_pin_output(col_pins[idx]);
         gpio_write_pin_low(col_pins[idx]);
     }
 }
 
 void ec_init(ec_config_t const* const ec_config) {
     // save config
     config = *ec_config;
 
     // initialize discharge pin as discharge mode
     gpio_write_pin_low(DISCHARGE_PIN);
     gpio_set_pin_output(DISCHARGE_PIN);
 
     // set analog reference
     analogReference(ADC_REF_POWER);
 
     // initialize drive lines
     init_col();
 
     // initialize multiplexer select pin
     init_mux_sel();
 
     // set discharge pin to charge mode
     gpio_set_pin_input(DISCHARGE_PIN);
 }
 
 uint16_t ec_readkey_raw(uint8_t col, uint8_t row) {
     uint16_t sw_value = 0;
 
     discharge_capacitor();
 
     select_mux(row);
 
     clear_all_col_pins();
 
     cli();
 
     charge_capacitor(col);
 
     sw_value = analogReadPin(ANALOG_PORT);
 
     sei();
 
     return sw_value;
 }
 
 bool ec_update_key(matrix_row_t* current_row, matrix_row_t col, uint16_t sw_value, uint16_t reset_pt, uint16_t actuation_pt) {
     bool current_state = (*current_row >> col) & 1;
 
     // press to release
     if (current_state && sw_value < reset_pt) {
         *current_row &= ~(MATRIX_ROW_SHIFTER << col);
         return true;
     }
 
     // release to press
     if ((!current_state) && sw_value > actuation_pt) {
         *current_row |= (MATRIX_ROW_SHIFTER << col);
         return true;
     }
 
     return false;
 }
 
 bool ec_matrix_scan(matrix_row_t current_matrix[]) {
     bool updated = false;
 
     for (int row = 0; row < sizeof(row_channels); row++) {
         for (int col = 0; col < sizeof(col_pins); col++) {
             uint16_t reset_pt = config.reset_pt;
             uint16_t actuation_pt = config.actuation_pt;
 
             switch(row) {
                 case 0:
                     switch(col) {
                         case 15: // lower threshold for split backspace:
                         case 16: // lower threshold for 2U backspace: 2U(37 rest, 62 btm)
                             reset_pt = 45;
                             actuation_pt = 50;
                             break;
                     }
                     break;
                 case 4:
                     switch(col) {
                         case 8: // Lower threshold for spacebar: 7U(37 rest, 63 btm)
                             reset_pt = 55;
                             actuation_pt = 60;
                             break;
                         case 13: // Lower threshold for right bottom mods: 1.5U(40 rest, 65 btm)
                             reset_pt = 47;
                             actuation_pt = 53;
                             break;
                     }
                     break;
             }
 
             ec_sw_value[col][row] = ec_readkey_raw(col, row);
             updated |= ec_update_key(&current_matrix[row], col, ec_sw_value[col][row], reset_pt, actuation_pt);
         }
     }
 
     return updated;
 }
 
 // console debugging for pad values
 /*void ec_dprint_matrix(void) {
     for (int row = 0; row < sizeof(row_channels); row++) {
         for (int col = 0; col < sizeof(col_pins); col++) {
             dprintf("%5d", ec_sw_value[col][row]);
         }
         dprintf("\n");
     }
 }*/