There are few problems which cannot be debugged with the healthy application of printf calls
@sir one is working with embedded systems that don’t have the ability to print out to a console.
@gbear605 can you blink an LED
@gbear605 in any case, I consider this a form of printf debugging. printf is a spectrum
@gbear605 I once was writing the display driver for KnightOS's TI-84+ CSE port and had to blink the backlight to extract debug info