diff options
Diffstat (limited to 'src/drivers/include/i2s_dac.hpp')
| -rw-r--r-- | src/drivers/include/i2s_dac.hpp | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/src/drivers/include/i2s_dac.hpp b/src/drivers/include/i2s_dac.hpp index fdd7e976..bd837ca0 100644 --- a/src/drivers/include/i2s_dac.hpp +++ b/src/drivers/include/i2s_dac.hpp @@ -27,10 +27,12 @@ namespace drivers { -// We normalise to 2-channel, 16 bit audio, which gives us a max of 4092 / 2 / 2 -// (16 bits) frames. This in turn means that at 48kHz, we have about 10ms of -// budget to fill each buffer. -constexpr size_t kI2SBufferLengthFrames = 512; +// DMA max buffer size for I2S is 4092. We normalise to 2-channel, 16 bit +// audio, which gives us a max of 4092 / 2 / 2 (16 bits) frames. This in turn +// means that at 48kHz, we have about 21ms of budget to fill each buffer. +// We base this off of the maximum DMA size in order to minimise the amount of +// work the CPU has to do to service the DMA callbacks. +constexpr size_t kI2SBufferLengthFrames = 1024; /** * Interface for a DAC that receives PCM samples over I2S. |