Thanks for the reply. I did think of signal strength issues, but it all looked good.

Well, as development and testing have progressed, I noticed similar problems with other modules, so retested the suspect module and it now appears to be not broken. Software problem(s) after all.

I have been having fun with what I now think is a broken M5 STAMP-Pico, which uses an ESP32 Pico chip. I spent a lot of time looking for a software error, before checking for bad hardware, as I'm actively developing and the module is brand new. I'm pretty sure it's a bad module, as other modules wor...

Hi, I am seeing an anomaly with the Wire library - not sure whether to call it an issue. My app, ported from AVR, has one or more MCP23008 expanders connected to one I2C bus, polled at 50 mS intervals. All I2C operations are performed in a single thread, using Wire. It all works fine when the pollin...