drashna/qmk_firmware
1
0
Fork 0
Code Activity Actions

fixes audio prescaler to emit correct freq

Browse source
This commit is contained in:
Jack Humbert 2016-04-16 20:26:02 -04:00
parent b8d2e66638
commit c83aa16f1d
3 changed files with 36 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

12
quantum/audio.c
View file

@ -12,6 +12,8 @@
#define PI 3.14159265
#define CPU_PRESCALER 8
// #define PWM_AUDIO
#ifdef PWM_AUDIO
@ -244,12 +246,12 @@ ISR(TIMER3_COMPA_vect) {
// ICR3 = (int)(((double)F_CPU) / frequency); // Set max to the period
// OCR3A = (int)(((double)F_CPU) / frequency) >> 1; // Set compare to half the period
voice_place %= voices;
if (place > (frequencies[voice_place] / 500)) {
if (place > (frequencies[voice_place] / 50)) {
voice_place = (voice_place + 1) % voices;
place = 0.0;
}
ICR3 = (int)(((double)F_CPU) / frequencies[voice_place]); // Set max to the period
OCR3A = (int)(((double)F_CPU) / frequencies[voice_place]) >> 1 * duty_place; // Set compare to half the period
ICR3 = (int)(((double)F_CPU) / (frequencies[voice_place] * CPU_PRESCALER)); // Set max to the period
OCR3A = (int)(((double)F_CPU) / (frequencies[voice_place] * CPU_PRESCALER)) >> 1 * duty_place; // Set compare to half the period
place++;
// if (duty_counter > (frequencies[voice_place] / 500)) {
// duty_place = (duty_place % 3) + 1;
@ -281,8 +283,8 @@ ISR(TIMER3_COMPA_vect) {
place -= SINE_LENGTH;
#else
if (note_frequency > 0) {
ICR3 = (int)(((double)F_CPU) / note_frequency); // Set max to the period
OCR3A = (int)(((double)F_CPU) / note_frequency) >> 1; // Set compare to half the period
ICR3 = (int)(((double)F_CPU) / (note_frequency * CPU_PRESCALER)); // Set max to the period
OCR3A = (int)(((double)F_CPU) / (note_frequency * CPU_PRESCALER)) >> 1; // Set compare to half the period
} else {
ICR3 = 0;
OCR3A = 0;