> is it possible to debug a Motorola MC 68040 via JTAG?
The MC68040 doesn't have any in-circuit-debug support.
Reply by Carsten Krueger●December 6, 20042004-12-06
Tauno Voipio <tauno.voipio@iki.fi.NOSPAM.invalid> wrote:
>If the stub is run interrupt-driven and the main code
>crash did not succeed in destroying the interrupt
>environment, you may still succeed in making a post-
>mortem of the crash.
>
> Interesting concept, but I don't know if I can use it. The problem is,
> what do I do if my programm is crashed.
> I think a stub is than "crashed", too.
It depends.
If the stub is run interrupt-driven and the main code
crash did not succeed in destroying the interrupt
environment, you may still succeed in making a post-
mortem of the crash.
IMHO, the main use is in normal debugging, i.e. running
until a breakpoint, looking at variables, etc.
I have written a stub for ARM7TDMI and run it
successfully for a couple of years. As there are
graphic front-ends for GDB, it is actually a nice
debugging environment for an embedded system.
Regards from Helsinki, the home city of Linux.
--
Tauno Voipio
tauno voipio (at) iki fi
Reply by Carsten Krueger●December 5, 20042004-12-05
Tauno Voipio <tauno.voipio@iki.fi.NOSPAM.invalid> wrote:
>GDB stub is a piece of code in the target system. The stub
>understands the GDB remote debugging protocol and functions
>as the GDB's resident agent reading and setting register
>contents, memory contents and breakpoints.
ok
>Googling 'gdb stub' gave about 43000 hits, at least the
>first couple of pages fully relevant to the question.
> larwe@larwe.com (Lewin A.R.W. Edwards) wrote:
>
>
>>I don't believe the 68040 has a JTAG port.
>
>
> It has, but I don't know which software is needed to use it.
>
>
>>If you want to use gdb on this processor, you will need to port gdb
>>stubs
>
>
> What is a stub?
>
GDB stub is a piece of code in the target system. The stub
understands the GDB remote debugging protocol and functions
as the GDB's resident agent reading and setting register
contents, memory contents and breakpoints.
The stub functioning and structure is documented in the
GDB sources and documentation.
Googling 'gdb stub' gave about 43000 hits, at least the
first couple of pages fully relevant to the question.
--
Tauno Voipio
tauno voipio (at) iki fi
Reply by Carsten Krueger●December 5, 20042004-12-05
larwe@larwe.com (Lewin A.R.W. Edwards) wrote:
>I don't believe the 68040 has a JTAG port.
It has, but I don't know which software is needed to use it.
>If you want to use gdb on this processor, you will need to port gdb
>stubs
Reply by Lewin A.R.W. Edwards●December 4, 20042004-12-04
> is it possible to debug a Motorola MC 68040 via JTAG?
I don't believe the 68040 has a JTAG port. All the hardware debuggers
I'm aware of for this processor are full ICEs that totally replace the
CPU.
If you want to use gdb on this processor, you will need to port gdb
stubs (I find it hard to believe that nobody has done this before...)
and connect over serial, Ethernet or whatever other interface is
readily available in your target system.
Reply by Carsten Krueger●December 4, 20042004-12-04