This is a bit complicated, technically, but I’ve been asked to document the issue just in case someone comes across it.
I was getting I2C read errors when using the new TE AmbiMate MS4 sensor board (review coming soon!) with the Raspberry Pi 4. I contacted TE about it and they asked me to try a Pi 3. So I did, and it worked absolutely fine.
It was an intermittent issue on the Pi 4 (everyone’s favourite sort of error!), and so I did some research and found some information on something called ‘clock stretching‘.
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