Rob Nertney wrote: > I can successfully play 32b@32KHz and 32b@16KHz to my I2S DAC. > > I can also, with the same settings as 32b@16KHz, play 16b@32KHz, but I > don't think this is the way ALSA wants its data.... > > I've learned that hw_params is responsible for describing only what the > hardware is supposed to be capable of. The hw_params values describe the format of the samples in memory. (If alsa-lib does format conversion, the application and the driver see different hw_params values.) What the hardware does with the samples after the DMA controller has read them from memory is of no concern to the ALSA framework. > Does this mean the hardware needs to find a way to pad 0's on lower > quality data for any given rate? If the hardware is capable of that, then the driver can support 16-bit samples. (I don't know of any I²S controller that cannot do that.) > For example, when I play 32b @32 KHz, everything works. If I play 16b@32KHz, > I shouldn't change any output clocks, but will also present the data on a > 32bit data bus as 16bits padded with 0? Which bus? The memory bus, or the I²S bus? Regards, Clemens _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
