Switch between DSP/BIOS tasks for debug

Andrey Gursky

Dear TI support and forum members,

I'm using ezdsp5502 board and experiencing a race condition issue by adding only one call to a DSP/BIOS related function, like printf or TSK_sleep(1) at some place. To investigate this problem further I'd like to see where are the other tasks at the moment with and without such a call (halting at breakpoint). E.g. gdb has "thread" command to perform such context switches, how can I do this for DSP/BIOS with CCS?

Thanks,
Andrey

over 10 years ago

0 Tom Kopriva over 10 years ago

TI__Mastermind 20480 points

Hi Andrey,

what version of DSP/BIOS and CCS are you using? In CCS5 and up, you can use "ROV"?

DSP/BIOS User manual: http://www.ti.com/lit/ug/spru423i/spru423i.pdf

0 Andrey Gursky over 10 years ago in reply to Tom Kopriva

Intellectual 350 points

Hi Tom,

Thanks for your response. I'm using DSP/BIOS 5.42.01.09 and CCS 6.1.0. Yes, ROV is good to see stack sizes, but I can't see a source line information where tasks are, when the CPU halts on a breakpoint. Only if some task sleeps waiting for semaphore.

0 Tom Kopriva over 10 years ago in reply to Andrey Gursky

TI__Mastermind 20480 points

Audrey,
sorry, support to see source line info wasn't ever implemented for DSP/BIOS.
With SYS/BIOS, ROV can view each Task's callstack. I think that could have helped you, but again, that's in SYS/BIOS.

0 Andrey Gursky over 10 years ago in reply to Tom Kopriva

Intellectual 350 points

Tom,

OK with no source line infos. But DSP/BIOS does know where to continue with the task execution (where it has been interrupted). So this program memory address with the last executed assembler instruction (or the next one to execute) is saved, but where?

Thanks,
Andrey

0 Karl Wechsler over 10 years ago in reply to Andrey Gursky

TI__Mastermind 20805 points

Every task has a stack. The register context is saved on those stacks. But, the register order, etc. is all buried in the assembly code implementation in DSP/BIOS and is not documented for outsiders. You might be able to use the "task switch hook" to save some stack information before you switch tasks. And use this to backtrack on your own. The switch hook is called with two parameters -- the 'from' and 'to' tasks. See section 4.4.4 of this document -- www.ti.com/.../spru423i.pdf

0 Andrey Gursky over 10 years ago in reply to Karl Wechsler

Intellectual 350 points

Karl, thanks for your suggestion.

I also thought about that, but before to start with this I hoped to get more information from insiders about TSK_Handle. Or there are no chances to get not all, but only limited related details for that?

Regards,
Andrey

Processors

Processors forum

Switch between DSP/BIOS tasks for debug