GDB debugging of ARM Core via OpenOCD

[hedg...@gmail.com]

Hey guys,

I just picked up a Buspirate to try and find something OpenOCD compatible so i could load up a gdb stub. I've triple checked the JTAG pin locations on J2, and it seems those connections are fine, and I know this reads in Vivado as expected using a Xilinx Platform Cable II, but when I try to open a gdbserver it seems to hard-stop immediately, and trying to communicate throws a "device needs to be examined first" error iirc. 

I saw that there was a JTAG boot mode, but i have no idea how that works or whats possible. 

Any idea how i could go about debugging this issue?

Thx,

Hedge

[weath...@krtkl.com]

Hi Hedge,

I'm not clear on what you are trying to do exactly.  Are you just trying to hookup an external JTAG to J2?
That definitely works but I'm not clear how OpenOCD is involved.

-Jamil

[hedg...@gmail.com]

Sorry, yeah wasn't as clear as it could have been. I'm using openocd since it has a gdb server, so i can control code execution from gdb and get a nice debugging interface. So, buspirate connects to J2 JTAG pins, openocd controls buspirate and exposes a gdb server. 

I haven't actually tested the buspirate sans gdb/openocd stuff so that might be something to try. I'll test that and post results + openocd config details when i get a chance. Anything else I can do that you guys could think of to pin issues down?