quantum/fauxclicky.c

   1 /*
   2 Copyright 2017 Priyadi Iman Nurcahyo
   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 This program is distributed in the hope that it will be useful,
   9 but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 GNU General Public License for more details.
  12 You should have received a copy of the GNU General Public License
  13 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  14 */
  15
  16 #include <avr/interrupt.h>
  17 #include <avr/io.h>
  18 #include <timer.h>
  19 #include <fauxclicky.h>
  20 #include <stdbool.h>
  21 #include <musical_notes.h>
  22
  23 bool     fauxclicky_enabled = true;
  24 uint16_t note_start         = 0;
  25 bool     note_playing       = false;
  26 uint16_t note_period        = 0;
  27
  28 void fauxclicky_init() {
  29     // Set port PC6 (OC3A and /OC4A) as output
  30     DDRC |= _BV(PORTC6);
  31
  32     // TCCR3A / TCCR3B: Timer/Counter #3 Control Registers
  33     TCCR3A = (0 << COM3A1) | (0 << COM3A0) | (1 << WGM31) | (0 << WGM30);
  34     TCCR3B = (1 << WGM33) | (1 << WGM32) | (0 << CS32) | (1 << CS31) | (0 << CS30);
  35 }
  36
  37 void fauxclicky_stop() {
  38     FAUXCLICKY_DISABLE_OUTPUT;
  39     note_playing = false;
  40 }
  41
  42 void fauxclicky_play(float note[]) {
  43     if (!fauxclicky_enabled) return;
  44     if (note_playing) fauxclicky_stop();
  45     FAUXCLICKY_TIMER_PERIOD = (uint16_t)(((float)F_CPU) / (note[0] * (float)FAUXCLICKY_CPU_PRESCALER));
  46     FAUXCLICKY_DUTY_CYCLE   = (uint16_t)((((float)F_CPU) / (note[0] * (float)FAUXCLICKY_CPU_PRESCALER)) / (float)2);
  47     note_playing            = true;
  48     note_period             = (note[1] / (float)16) * ((float)60 / (float)FAUXCLICKY_TEMPO) * 1000;
  49     note_start              = timer_read();
  50     FAUXCLICKY_ENABLE_OUTPUT;
  51 }
  52
  53 void fauxclicky_check() {
  54     if (!note_playing) return;
  55
  56     if (timer_elapsed(note_start) > note_period) {
  57         fauxclicky_stop();
  58     }
  59 }