quantum/encoder.c

   1 /*
   2  * Copyright 2018 Jack Humbert <jack.humb@gmail.com>
   3  *
   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.
   8  *
   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.
  13  *
  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  */
  17
  18 #include "encoder.h"
  19
  20 // for memcpy
  21 #include <string.h>
  22
  23
  24 #ifndef ENCODER_RESOLUTION
  25   #define ENCODER_RESOLUTION 4
  26 #endif
  27
  28 #ifndef NUMBER_OF_ENCODERS
  29   #error "Number of encoders not defined by NUMBER_OF_ENCODERS"
  30 #endif
  31
  32 #if !defined(ENCODERS_PAD_A) || !defined(ENCODERS_PAD_B)
  33   #error "No encoder pads defined by ENCODERS_PAD_A and ENCODERS_PAD_B"
  34 #endif
  35
  36 static pin_t encoders_pad_a[NUMBER_OF_ENCODERS] = ENCODERS_PAD_A;
  37 static pin_t encoders_pad_b[NUMBER_OF_ENCODERS] = ENCODERS_PAD_B;
  38
  39 static int8_t encoder_LUT[] = { 0, -1, 1, 0, 1, 0, 0, -1, -1, 0, 0, 1, 0, 1, -1, 0 };
  40
  41 static uint8_t encoder_state[NUMBER_OF_ENCODERS] = {0};
  42
  43 #ifdef SPLIT_KEYBOARD
  44 // slave half encoders come over as second set of encoders
  45 static int8_t encoder_value[NUMBER_OF_ENCODERS * 2] = {0};
  46 #else
  47 static int8_t encoder_value[NUMBER_OF_ENCODERS] = {0};
  48 #endif
  49
  50 __attribute__ ((weak))
  51 void encoder_update_user(int8_t index, bool clockwise) { }
  52
  53 __attribute__ ((weak))
  54 void encoder_update_kb(int8_t index, bool clockwise) {
  55   encoder_update_user(index, clockwise);
  56 }
  57
  58 void encoder_init(void) {
  59   for (int i = 0; i < NUMBER_OF_ENCODERS; i++) {
  60     setPinInputHigh(encoders_pad_a[i]);
  61     setPinInputHigh(encoders_pad_b[i]);
  62
  63     encoder_state[i] = (readPin(encoders_pad_a[i]) << 0) | (readPin(encoders_pad_b[i]) << 1);
  64   }
  65 }
  66
  67 void encoder_read(void) {
  68   for (int i = 0; i < NUMBER_OF_ENCODERS; i++) {
  69     encoder_state[i] <<= 2;
  70     encoder_state[i] |= (readPin(encoders_pad_a[i]) << 0) | (readPin(encoders_pad_b[i]) << 1);
  71     encoder_value[i] += encoder_LUT[encoder_state[i] & 0xF];
  72     if (encoder_value[i] >= ENCODER_RESOLUTION) {
  73         encoder_update_kb(i, false);
  74     }
  75     if (encoder_value[i] <= -ENCODER_RESOLUTION) { // direction is arbitrary here, but this clockwise
  76         encoder_update_kb(i, true);
  77     }
  78     encoder_value[i] %= ENCODER_RESOLUTION;
  79   }
  80 }
  81
  82 #ifdef SPLIT_KEYBOARD
  83 void encoder_state_raw(uint8_t* slave_state) {
  84   memcpy(slave_state, encoder_state, sizeof(encoder_state));
  85 }
  86
  87 void encoder_update_raw(uint8_t* slave_state) {
  88   for (int i = 0; i < NUMBER_OF_ENCODERS; i++) {
  89     encoder_value[NUMBER_OF_ENCODERS + i] += encoder_LUT[slave_state[i] & 0xF];
  90     if (encoder_value[NUMBER_OF_ENCODERS + i] >= ENCODER_RESOLUTION) {
  91         encoder_update_kb(NUMBER_OF_ENCODERS + i, false);
  92     }
  93     if (encoder_value[NUMBER_OF_ENCODERS + i] <= -ENCODER_RESOLUTION) { // direction is arbitrary here, but this clockwise
  94         encoder_update_kb(NUMBER_OF_ENCODERS + i, true);
  95     }
  96     encoder_value[NUMBER_OF_ENCODERS + i] %= ENCODER_RESOLUTION;
  97   }
  98 }
  99 #endif