MicroPython has a mechanism for performing continuous asynchronous stream reading in asyncio.StreamReader. A means of instantiating a StreamReader from an ADC would have applications beyond sourcing UDP data and might be more likely to win approval from the maintainers.

Thanks for suggesting asyncio.StreamReader. I am actually implementing a voice recorder (without audio codec chip) which uploads to a smart-home compute node. Since audio sampling rate is typically 16000Hz or 44100Hz, execution speed is critical. That is why even TCP might not be fast enough because of all the handshake and acknowledgement packets. I think the only reasonable application case is to either store it locally (e.g., 5 seconds speech at 16kHz will take ~160KB) or send over UDP. But someone can try to see how to fit into the StreamReader framework.