[ECOS] GDB for MIPS

[Jonathan Larmour]

Michael Anburaj wrote:
> Many thanks to Nick & Jonathan.
> 
> Now my GDB stub breaks at the break exception (upon hitting a break 
> point). I am not sure what the target should send to intimate this break 
> point condition. Is there a document for this? (Or the other approach is 
> to learn from Redboot source – which I am doing also...).
> 
> 
> Redboot's response:
> 
> c c
> w $Z0,a01001b8,4#03
 > r +$OK#9a

RedBoot understands the $Z packet way of setting breakpoints.


> w +$Hc0#db
> r +$OK#9a
> w +$c#63
> r +$T05thread:00000000;25:b80110a0ffffffff;1d:ffffffff905210a0;#1b
> w +$g#67
> 
> 
> My Debug monitor's response:
> 
> c c
> w $Z0,a01001b8,4#03
> r +$#00

YAMON doesn't understand $Z, so GDB does it by steam with memory reads/writes.

> w +$ma01001b8,4#ba
> r +$55000224#92
> w +$Ma01001b8,4:0d000500#8d
> r +$OK#9a
> w +$Hc0#db
> r +$#00
> w +$c#63

Everything up to here is fine.

> r +$S05#b8

Target reported stopped with signal 5 using $S rather than $T. Not a 
problem - just less efficient.

> w +$g#67

And whatever response YAMON gave to this includes something which 
indicates the program is stopped at 0x3, which is presumably wrong. So 
YAMON is sending bogus register data probably. You'd have to pick through 
the response to find out exactly what it's sending for what registers (and 
I'm not volunteering).

Jifl
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