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Max32 interrupt problems

Created Mon, 01 Oct 2012 17:48:12 +0000 by mstachowsky


Mon, 01 Oct 2012 17:48:12 +0000

Hi all,

I'm having some troubles with the interrupts. I THINK it's a hardware problem (the same basic code worked on my Arduino mega). I put a hall effect encoder onto one of the interrupts (it doesn't matter which one. The problem is still there if it's interrupt 0, 2, or 4). The encoder is powered by the 3.3V line on the Max32, which is itself powered via USB.

This is the same setup that I was using with the arduino, except everything was 5V at that time. The encoder's input voltage is between 3.3 and 6V, so I'm good there.

As the encoder spins, sometimes it'll send the board into a weird buggy mode where all it does is rapidly oscillate voltages all over the place. The 3.3V output line goes between 0 and 3.3V, while the digital IO pins do the same thing.

Are the interrupts 5V tolerant? (I'm not sure what the encoder is outputting. I think it's 3.3V, but I'll have to check when I get in tomorrow). Can anyone think of anything else it might be? I'm pulling up the interrupt lines with a 10K resistor, and the rest of the circuit works perfectly fine until the interrupts are turned on.





Sat, 13 Oct 2012 08:34:33 +0000

exactly what trouble with the interruptions? Describe it, put the code. Do note that the interrupt vectors are different between arduino and max32, and also the ISR. You could and blink pins when interruptions happen and check with a scope.