Re: ARM7, remote GDB, Software Breakpoints

Torsten Mohr
2003-02-12T20:20:20Z

Hi,

thanks for your hint.

> > 1. I could handle HW breakpoints, how can i tell GDB that it should
> > use HW breakpoints? Just answering requests for SW breakpoints with
> > "ENN" doesn't seem to make GDB use HW breakpoints.
>
> You have to implement commands starting with 'Z' and 'z' in order to
> support hw breakpoints.

Yes, i do that. According to GDB remote protocol, when i answer
a request for "Z0..." with "ENN" (means "i can't handle software
breakpoints"), GDB doesn't try hardware breakpoints.

But maybe, when i have some hardware that doesn't run in RAM,
but in Flash-ROM, i think i'd rather like to have HW breakpoints.
Also, when i don't answer with "ENN", but with "" (empty),
GDB doesn't try HW breakpoints.

> It is very strange, because gdb works exactly this way. I am wondering do
> you have 'step' command implemented?

Oops, my misinterpretation of that protocol. Yes, it just works
as it is. Great.

> > 3. Thumb mode is not handled at all at the moment, what do i need
> > to do to handle Thumb mode?
> > If GDB downloads a program into the target and sets the PC to a
> > certain address, how does my server know if it should execute this
> > in ARM or in Thumb mode?

Thanks,
Torsten.