Quad Audio with NRF52840

[riataman]

Hey, I see that the nrf52840 has a single i2s peripheral. and the max sample witdh supported is 24bits. Is there any way to get 4 channel 16bit audio? I only need to record about ~1second of audio data to send. REading the produc spec doesn't seem to be any way as the single i2s pheripherical only supports stereo audio (no TDM) nor does it have parallel input.

Any suggestions short of recording the data in another micro and then transfering to the nrf via spi?

[haakonsh]

Hey riatman,

Do you need to sample both "dual" channels at the same time or can you TDM between two sets of channels? If so then you can just swap the io pins in the driver. 

Cheers,

Håkon.

[riataman]

Unfortunately all 4 channels need to be in phase :(

[haakonsh]

Then I'm afraid you will not be able to this in HW. You might be able to bit-bang the other two channels, but we do not have a solution with that problem. You will have to get creative with GPIOTE, PPI, and TIMERs.