So I had the GPIO diagram upside down (haha). SO I connected the 5V Power pin on the header to the 3.3V Power pin on the GPIO. It was only for a second or less. My RPi still works fine, but I wonder if I should now consider this board suspect?

  • I can't imagine any situation which would require connecting 2 Pi expansion connector (not GPIO) pins together or how having the diagram upside down would connect a expansion connector 3.3V to 5V so it is difficult to make any sensible comment. – Milliways Jun 6 '16 at 12:11
  • 1
    Not to say that it couldn't cause harm, but if everything is currently working you probably got lucky. It is not a conventional short. – goldilocks Jun 6 '16 at 12:31
  • Thanks for the responses. To clarify, I was trying to connect header pin #39 to header pin #40. If done correctly, this connects GPIO21 to GND. But instead I connected header pin #1 to header pin #2, this connects the 5v output to the 3.3v output. Was wondering if anyone knew for sure if the 3.3v output has defenses that can cope with having 5v forced down its throat. – Mike Jun 7 '16 at 4:40
  • 1
    +1 on that question! I connected 5V output of a board (16-Channel 12V Relay Module) to 3.3V output of Pi. Gnd was also connected to Gnd. It stayed connected for several secons. – visoft Nov 17 '17 at 11:07
  • @visoft - Tell us about it - with pictures - and perhaps you too could gain an un-coveted rip tag...! – SlySven Dec 15 '18 at 0:05

Did any of the magic blue smoke get out? Also, what was on the other end of the lead that you were connecting to the RPi's GPIO Header? Those supplies on pins 1 and 2 (the end away from the Ethernet/USB connectors are normally to supply power to connected hardware (but the 5V can be used as a power input to the RPi - I have a RPi specific UPS that does that). Depending on what the connected stuff was you might have got away with it provided that the ground connections further towards the middle did not short out the RPi GPIO pins that actually connect to I/O lines on the SoC if they too got swapped over.

Perhaps after this time you are in a better position to judge. If you can come back to us you on this you may be in-line to get a tag for this question - as it is I guess this rates an honourable mention! 8-)

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.