AVR-Arduino Hardware Debugger on the Cheap 

I’ve posted a new, part 3 article on my debugger project, along with new code and an overview video. The new code is now able debug an Arduino UNO running at 16 MHz and also includes some bug fixes and enhancements.
sites.google.c...
This video shows how you can use an Arduino sketch running on one Arduino to control and debug another Arduino, or an AVR-Series micro-controller such as an ATTiny85. With some limitations, you can use the controlling Arduino to disassemble code, single step code, inspect the current value of registers. I/O ports and SRAM and run code with a hardware breakpoint set. And, all you need to do this is the RESET pin on the target device, a 10K resistor pulling RESET to Vcc, and a standard, ATMega328-based Arduino to act as the controlling debugger.
For more details, see: sites.google.c...