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:export_failed when trying to open a specific GPIO pin

/nerves#raspberrypi
benwilson512

benwilson512

Author of Craft GraphQL APIs in Elixir with Absinthe

:export_failed when trying to open a specific GPIO pin

Hey folks! I’ve been working with a Raspberry Pi 3b+ and nerves as part of a very fun espresso machine project. For some reason GPIO pin 5 specifically has this issue:

{:ok, gpio5} = Circuits.GPIO.open(5, :input, pull_mode: :pulldown)
** (MatchError) no match of right hand side value: {:error, :export_failed}
    (stdlib 4.1.1) erl_eval.erl:496: :erl_eval.expr/6
    iex:4: (file)

GPIO pin 4 also behaves this way, but I have the 1 wire protocol enabled for that pin which makes sense to me. Anything I could be missing that would prevent pin 5 from being usable?

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fhunleth

fhunleth

Co-author of Nerves

Sorry for the late reply. I somehow missed this post. GPIO 5 (physical pin 29) works for me. Did you find the issue?

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