chipKIT® Development Platform

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Digital I/O pin problems

Created Sun, 14 Oct 2012 22:55:10 +0000 by Jerf80


Sun, 14 Oct 2012 22:55:10 +0000

Hi all,

I have a project where I must drive several strands of digital RGB LEDs:

I'm using a MAX32 board with mpide. My initial tests using software "bit-banging" have worked great using the library that ADAFruit supplies:

My initial tests were all using ChipKit pin 22 for data and 23 for clock. The problem I'm encountering is I can't seem to get any other pins to work.

I've tried: 24 and 25, 26 and 27, etc all the way up to 52 and 53. I've also tried 14 and 15, 16 and 17.

So my question is, is there anything I can change in the libraries to make these pins function for what I'm trying to do? Are there any other pins on the board that are suitable for this? I need a total of 16 pins (8 pairs).




Mon, 15 Oct 2012 00:11:27 +0000


As far as I can tell from just reading the code in that library, there's nothing that should prevent it from working on any arbitrary IO pin.

Can you post the sketch that works and the one that doesn't work and I'll see if I can find the problem.



Thu, 18 Oct 2012 19:26:17 +0000

I think it's more likely a problem of having another function shared to the pins you're using for the library. But without the sketch it's rather hard to troubleshoot this issue, I'm afraid.

Have you looked in the reference manual to see if any other pins are being used etc?

Which pins are you using? Any peripherals attached etc?