Correct! There is a debugger in MESS (which also emulates the 7800), however I'm not a MESS user.
Okay, MESS debugger working. So indeed, newer tools are better
I have the source code for Commando, as well as the Atari 7800 Development System. Assuming that I have knowledge on programming for the system, what are the steps I need to take to compile the code and run it in a tester/debugger?