I2s support on Impc001


#1

I need to add a digital mems microphone to IMPC001 device.
What can this device support for digital audio in terms of I2S, PCM, PDM, analog interfaces etc ?


#2

In theory, the hardware supports a DFSDM digital microphone in the same way that the imp004m does, which allows direct connection to the imp - however, this API is not yet available on impC001. You can use the analog input with a mic preamp and the sampler peripheral as you would with imp002/003, though.

Can you give any more info about your application?


#3

Hugo,

        We can use PDM microphones here but what pins on IMPC001 do we connect to for clock and data ?

The application is for monitoring noise events in cities etc. Can we send say short wav file of the noise event via IMP server and onto Losant platform ?


#4

As noted, PDM mic support is not enabled on impC001 at this point (it’s only on the imp004m). But, if/when it is enabled, you’d be able to use a PDM mic. Until then you can use an analog mic with preamp.

Yes you can record a short wav file at whatever sample rate you want and send it to the cloud. I’m not sure how Losant deals with WAV files but we can get the data to them.


#5

Hugo,
Do you know at this stage, what I/O pins on the IMPC001 will support PDM microphone input ? We need 2 pins for CLK and Data to interface with DFSDM block.


#6

As noted, DFSDM is not yet supported, but the pins you would need to use are pinYU for data and pinYR for clock.

Contact us by email to discuss your application if you’d like this to be added - right now DFSDM has not been prioritized as there are other features that customers need sooner (BLE, ethernet, wifi).