diff options
| author | Nebuleon <2391500+Nebuleon@users.noreply.github.com> | 2023-09-24 22:26:32 -0400 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2023-09-25 12:26:32 +1000 |
| commit | 2f4e1a78ad98fce1da056715aa5304dfdc9c7c49 (patch) | |
| tree | 7d239532b1659c90b00800469a4d845784ccca4b /platforms | |
| parent | 1d94de5358a44e08d9c1a07ab76df0b85d029ab7 (diff) | |
Reduce popping during audio initialization using the additive DAC (#21642)
Diffstat (limited to 'platforms')
| -rw-r--r-- | platforms/chibios/drivers/audio_dac_additive.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/platforms/chibios/drivers/audio_dac_additive.c b/platforms/chibios/drivers/audio_dac_additive.c index 7bb5cfffb5..26e044b048 100644 --- a/platforms/chibios/drivers/audio_dac_additive.c +++ b/platforms/chibios/drivers/audio_dac_additive.c @@ -84,7 +84,7 @@ static const dacsample_t dac_buffer_trapezoid[AUDIO_DAC_BUFFER_SIZE] = {0x0, 0 0xfff, 0xfdf, 0xf7f, 0xf1f, 0xebf, 0xe5f, 0xdff, 0xd9f, 0xd3f, 0xcdf, 0xc7f, 0xc1f, 0xbbf, 0xb5f, 0xaff, 0xa9f, 0xa3f, 0x9df, 0x97f, 0x91f, 0x8bf, 0x85f, 0x7ff, 0x79f, 0x73f, 0x6df, 0x67f, 0x61f, 0x5bf, 0x55f, 0x4ff, 0x49f, 0x43f, 0x3df, 0x37f, 0x31f, 0x2bf, 0x25f, 0x1ff, 0x19f, 0x13f, 0xdf, 0x7f, 0x1f, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}; #endif // AUDIO_DAC_SAMPLE_WAVEFORM_TRAPEZOID -static dacsample_t dac_buffer_empty[AUDIO_DAC_BUFFER_SIZE] = {AUDIO_DAC_OFF_VALUE}; +static dacsample_t dac_buffer[AUDIO_DAC_BUFFER_SIZE]; /* keep track of the sample position for for each frequency */ static float dac_if[AUDIO_MAX_SIMULTANEOUS_TONES] = {0.0}; @@ -311,10 +311,17 @@ void audio_driver_initialize(void) { DACD1.params->dac->CR &= ~DAC_CR_BOFF1; DACD2.params->dac->CR &= ~DAC_CR_BOFF2; + /* Start the DAC output with all off values. This buffer will then get fed + * with samples from dac_end, which will play notes. + */ + for (size_t i = 0; i < AUDIO_DAC_BUFFER_SIZE; i++) { + dac_buffer[i] = AUDIO_DAC_OFF_VALUE; + } + if (AUDIO_PIN == A4) { - dacStartConversion(&DACD1, &dac_conv_cfg, dac_buffer_empty, AUDIO_DAC_BUFFER_SIZE); + dacStartConversion(&DACD1, &dac_conv_cfg, dac_buffer, AUDIO_DAC_BUFFER_SIZE); } else if (AUDIO_PIN == A5) { - dacStartConversion(&DACD2, &dac_conv_cfg, dac_buffer_empty, AUDIO_DAC_BUFFER_SIZE); + dacStartConversion(&DACD2, &dac_conv_cfg, dac_buffer, AUDIO_DAC_BUFFER_SIZE); } // no inverted/out-of-phase waveform (yet?), only pulling AUDIO_PIN_ALT to AUDIO_DAC_OFF_VALUE |