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From: Theo <theom+news@chiark.greenend.org.uk>
Newsgroups: comp.sys.raspberry-pi
Subject: Re: Need help with PI PICO...
Date: 24 Mar 2024 14:45:58 +0000 (GMT)
Organization: University of Cambridge, England
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The Natural Philosopher <tnp@invalid.invalid> wrote:
> As you can see from my last reply that is roughly where I am headed. Or 
> similar. Lacking full ICE., its all a bit 'poke the black box with 
> different sized sticks, and try and infer from what it does, what is 
> happening inside it'

One of the challenges with embedded debugging is that printf can be a very
slow thing, because it's spitting out characters on a slow UART. Adding
printfs can thus screw up timing.

Other techniques include writing things to memory you pick up later (don't
forget that string handling and especially sprintf formatting can be slow)
and wiggling GPIOs (eg output a different number in each stage of the
program).

sigrok is logic analyser software that works with cheap (<$10) capture
hardware - seems it can now use a Pi Pico for that as well.

Theo