[ECOS] Setting breakpoints

[Øyvind Harboe]

I'm developing an app that will run from flash,
so setting breakpoints isn't straightforward,
since it would require hardware breakpoints.

As an alternative approach, I was considering
changing the section of the function I needed
to debug to a section that runs from RAM.

I can't fit my entire app and eCos into RAM, 
but it shouldn't be a problem to fit enough of my 
app into RAM that setting breakpoints shouldn't
be a problem.

Q: Is this the right approach?
Q: What section do I place the functions in question into?
E.g.

int __attribute__ ((section (".fini")))  main(int argc, char **argv)

Q: I tried recompiling and running my app with the modification
above, but when I set a breakpoint in main, main was still in
the flash address space. Hmmm?





A bit about my setup:

- EB40a Atmel AT91R40008
- 2MB flash, 256Kb RAM
- JTAG Wiggler debugger + LibRemote app from GDB 
"target remote" to JTAG speak translation.
- When I try "hbreak main", I get an error message that hardware
breakpoints aren't supported. Similarly with "monitor set hbreak".
I don't know if the CPU supports hardware breakpoints, or whether
this is a limitation in my tools.

Øyvind


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