Breakpoint question

[kai]

I want to set a breakpoint so I can examine registers let's say in the firmware at address 46a4a0. I did reset 1, init, and tried go 46a4a0 and go= 46a4a0 and I had to exit the program to get control again. Those are good addresses in the 7.93 code. Am I missing something?

[patsfan]

i don't know why the program crashes. the "go" command is used to start or stop executed code. the address you're trying must be in the middle of a routine that when it crashes everything stops. i think the "r" command is supposed to show the registers when used by itself.

[usbbdm]

Motorola does not have break register.
So the go address is really a single step.
So if your program will stop in a few thousand instructions, that is fine, but if you want to stop anywhere, you might never get there since each instruction the BDM will check the RPC register. Which is really slow.
If you think you need to break at certain address, I use BGND instruction and reprogram the flash and run. New Motorola CPU support break register which is much better.

[kai]

Maybe I wasn't waiting long enough. I'll try the BGND instruction

I found that by using the t= command, at least I can start at some point of my choosing and trace through the code.

[kai]

Motorola does not have break register.
So the go address is really a single step.
So if your program will stop in a few thousand instructions, that is fine, but if you want to stop anywhere, you might never get there since each instruction the BDM will check the RPC register. Which is really slow.
If you think you need to break at certain address, I use BGND instruction and reprogram the flash and run. New Motorola CPU support break register which is much better.

Can I put a BGND (4A FA) in the firmware of the 2244 and issue a go command in the BDM and will it stop at the BGND instruction?