1

I'd like to use some special pins like 5 (scl) and 12 (pcm_clk)as regular pins to read from them. I made a circuit as shown here:

enter image description here

and setup all connected pins like this:

GPIO.setup(pin, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
GPIO.add_event_detect(pin, GPIO.RISING, callback=onTrigger, bouncetime=700)

All regular pins are Ok, but pins 5 and 12 continuously invoke onTrigger function with closed switches despite I set big bouncetime. How can I fix this?

  • 1
    There is nothing to fix. There is something wrong with either your wiring or your software. We need to see both to be able to usefully comment. – joan Sep 3 '18 at 14:54
2

It looks like when the button is pushed, you have an internal pull-down fighting against an external pull-up. Perhaps you should drop the internal pull-down in your code, since the schematic is clearly designed to work with pull-ups.

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