USB to DSP using i2s on xcore-200 MC
Posted: Thu Mar 01, 2018 4:53 pm
I wonder if it's possible to connect an external codec to the xcore-200 mc dev board (https://www.xmos.com/support/boards?product=18334) using i2s with the codec as i2s master? In my case the external codec is a custom audio-board equipped with DSP, DAC and ADC. The audio-board has been successfully used for bi-directional i2s with Raspberry Pi, audio-board as i2s master.
The present application is to use xmos to handle usb audio (and dsd over usb) and to pass the audio data to the audio-board for processing. I have tried the following:
Compiled and downloaded the pre-defined configuration - app_usb_aud_xk_216_mc_2i10o10xxxxxx_slave.xe. Have connected the xcore pins SCLK, LRCLK and xDAC_SD1 to the corresponding pins on the audio-board. With i2s enabled on the audio-board, SCLK=6.1MHz and LRCLK=96kHz. Evidently, I have missed something since the xcore also outputs clock signals on startup, xcore SCLK=12.3MHz , LRCLK=192kHz. I thought that _slave at the end of the app, app_usb_aud_xk_216_mc_2i10o10xxxxxx_slave.xe, meant that the application is expecting external clock signals on SCLK and LRCLK.
Anyone that have experience of connecting xcore-200 mc and external codec, where the codec is the master?
The present application is to use xmos to handle usb audio (and dsd over usb) and to pass the audio data to the audio-board for processing. I have tried the following:
Compiled and downloaded the pre-defined configuration - app_usb_aud_xk_216_mc_2i10o10xxxxxx_slave.xe. Have connected the xcore pins SCLK, LRCLK and xDAC_SD1 to the corresponding pins on the audio-board. With i2s enabled on the audio-board, SCLK=6.1MHz and LRCLK=96kHz. Evidently, I have missed something since the xcore also outputs clock signals on startup, xcore SCLK=12.3MHz , LRCLK=192kHz. I thought that _slave at the end of the app, app_usb_aud_xk_216_mc_2i10o10xxxxxx_slave.xe, meant that the application is expecting external clock signals on SCLK and LRCLK.
Anyone that have experience of connecting xcore-200 mc and external codec, where the codec is the master?