Make it Fail

(David J. Agans)

The quote is from Dave’s book Debugging: the 9 indispensable rules for finding even the most elusive software and hardware problems, which I recommend to everybody who has to debug a technical artifact.

dw-link: A New Hardware Debugger for ATtinys and Small ATmegas

As mentioned in an earlier blog post this year, hardware debuggers are the premier class of embedded debugging tools. However, until today, there were only very few relatively expensive tools around supporting the debugWIRE interface that is used by the classic ATtinys and a few ATmega MCUs.

The good news is that now you can turn an Arduino Uno, Nano, or Pro Mini into a debugWIRE hardware debugger that communicates with avr-gdb, the AVR version of the GNU project debugger.

Continue reading

Surprise, Surprise!

The featured image of this post is by Albert Guillaume – Gils Blas, 24 d├ęcembre 1895, Public Domain, Link

When you develop a tool for a protocol that is undocumented, it is not surprising that you will encounter situations you will not have be anticipated. And this was exactly what I experienced developing the hardware debugger dw-link, which connects debugWIRE MCUs to the GDB debugger. Although a substantial part of the debugWIRE protocol has been reverse engineered, I encountered still plenty of surprising situations: Split personality MCUs, stuck-at-one bits in program counters, secret I/O addresses, half-legal opcodes, and more.

Continue reading

Copyright © 2022 Arduino Craft Corner

Theme by Anders NorenUp ↑