Nulo/qmk_firmware
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fade envelope

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This commit is contained in:
Jack Humbert 2016-04-20 23:16:39 -04:00
parent 2e303b40ae
commit 2e60054951
1 changed files with 12 additions and 9 deletions
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21
quantum/audio.c
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@ -302,18 +302,19 @@ float vibrato(float average_freq) {
float envelope(float f) { float envelope(float f) {
uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / f)); uint16_t compensated_index = (uint16_t)((float)envelope_index * (880.0 / f));
switch (compensated_index) { switch (compensated_index) {
case 0: case 0 ... 9:
note_timbre = TIMBRE_50; f = f / 4;
break;
case 20:
note_timbre = TIMBRE_25;
break;
case 32:
note_timbre = TIMBRE_12; note_timbre = TIMBRE_12;
break; break;
case 40 ... 60: case 10 ... 19:
f = f / 2; f = f / 2;
note_timbre = TIMBRE_50; note_timbre = TIMBRE_12;
break;
case 20 ... 200:
note_timbre = .125 - pow(((float)compensated_index - 20) / (200 - 20), 2)*.125;
break;
default:
note_timbre = 0;
break; break;
} }
return f; return f;
@ -414,6 +415,8 @@ ISR(TIMER3_COMPA_vect) {
} }
freq = envelope(freq); freq = envelope(freq);
if (freq < 30.517578125)
freq = 30.52;
ICR3 = (int)(((double)F_CPU) / (freq * CPU_PRESCALER)); // Set max to the period ICR3 = (int)(((double)F_CPU) / (freq * CPU_PRESCALER)); // Set max to the period
OCR3A = (int)((((double)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); // Set compare to half the period OCR3A = (int)((((double)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre); // Set compare to half the period
} }