i2smic.py vs dtoverlay=googlevoicehat-soundcard

[mikeysklar]

A flurry of I2S issues popped up in the forums with regards to setting up the SPH0645 on Legacy Pi OS. The current guide involves compilation of modules which can result in compilation failure. 32-bit vs 64-bit mismatch and other reasons.

One user pointed out using the the googlevoicehat module just works. It is a single line change with no other configuration necessary to start recording with the SPH0645 I2S MEMS mic.

dtoverlay=googlevoicehat-soundcard

I've tested this on 32-bit / 64-bit PiOS Bullseye Legacy and Bookworm. They all produce valid sound files. Pi Zero and Pi4 hardware.

Does it make sense for me to update the guide and not use i2smic.py for this device?

[makermelissa]

Yes, let's go ahead with that. Using built-in Device Tree Overlays is preferable from a support/future proofing standpoint.

[mikeysklar]

Okay, I will update the SPH0645 guide to suggest the single line addition to config.txt. It appears the googlevoicehat module has been available in some form since 2017 so it looks like a stable option going forward.

[mikeysklar]

I updated the first half of the guide page to use the one liner config.txt mod with the googlevoicehat-soundcard.

The volume control would still be nice, but I need to verify it takes with the new driver so I've not modified that part of the page yet. I did add a warning that volume control does not work as is.

[mikeysklar]

Kind of a bummer, but no volume control / mic gain with the googlevoicehat-soundcard dtoverlay.