Hello
I want to record 8 channels from TIDA-01454 CMB into a Beaglebone AI. As the CMB is built with two PCM1864 ADCs and it is also a Beagle board, I followed this guide(https://www.ti.com/lit/an/sprac97/sprac97.pdf) with some changes(channels_max=16) in order to make it compatible with Beaglebone AI.
Connecting the 4 CMB Data pins to the Beaglbone AI mcasp pins, I have managed to record audio from 4 of the 8 microphones that the CMB has(I just tap the mic to check if that one is working). However I want to record the 8 channels/mics(I dont know how you technically call them). Currently the microphones I can record are MIC1, MIC4, MIC5 and MIC8, although I would say there is much noise.The CMB has 4 data output pins, I suppose each one transmits 2 channels, so the problem is that each pin is getting mono instead of stereo.
I already know that the output of the CMB is correct, each pin 2 channels, because I checked with an external I2S DAC the 4 pins:
Data 1 is giving MIC1 and MIC2
Data 2 is giving MIC5 and MIC6
Data 3 is giving MIC3 and MIC4
Data 4 is giving MIC7 and MIC8
So this means the problem is when receiving the data in the Beaglebone AI. This might be because a problem in DTS, therefore you can see my DTS File here: https://sharetext.me/o41nwo7olg
The serial-dir is that way because I use mcasp1_axr0, mcasp1_axr1, mcasp1_10 and mcasp1_axr11 ,those are the ones available in Beaglbone AI. I connected the pins DATA1-MiniDSP, DATA2-MiniDSP, DATA3-MiniDSP and DATA4-MiniDSP in J5(of the CMB) to these pins in my Beaglebone:
- P9.18b 173 fast rx 0 mcasp 0 d0 mcasp@48460000 (mcasp1_pins)
- P9.17b 174 fast rx 0 mcasp 0 d1 mcasp@48460000 (mcasp1_pins)
- P9.30 183 fast rx 0 mcasp 0 d10 mcasp@48460000 (mcasp1_pins)
- P9.28 184 fast rx 0 mcasp 0 d11 mcasp@48460000 (mcasp1_pins)
So what am I doing wrong? If you need any more info or files(alsa.conf, CMB configuration…) just let me know. How can I record all the channels when using arecord -f S16_LE -r 96000 -D hw:1,0 -d 15 -c 8 test.mp3