Python • Re: RuntimeError: Failed to add edge detection

Seems to be, whichever 'RPi.GPIO' this is, it has determined the revision code of the Pi hardware to be in the old-style format which shouldn't be the case for a Pi 3B+.

Only a few Pi should be using old-style revision codes; A, B, A+, B+, plus a couple of older CM variants.

I've run in to this problem with a Pi 1B. I get "RuntimeError: Failed to add edge detection" with python3-rpi.gpio and "NotImplementedError: This module does not understand old-style revision codes" with python3-rpi-lgpio.

Solution is to specify the 'new-style' RPi board revision code as an environment variable for RPi1 and some RPi2 models (page 4 here). E.g., for the RPi1 B+ v1.2 made by Sony in the UK, the code is 900032.

Statistics: Posted by vzzbcks — Mon Mar 24, 2025 6:41 pm

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