How do you insert a Software Breakpoint for F28M36 (C28 as well as M3)?

Steve Goodrich

How do I insert a software breakpoint in source code for the C2000 (F28M36, C28 side)? I'm debugging code in flash/rom, and the number of available hardware breakpoints (1) is insufficient for my needs. I want to do something like:

if (!ReadPosition(&posn)) {
Log("Unable to read position, error = %d\n", getLastError());
SW_BREAKPOINT(); // software breakpoint instruction
}

While I'm asking: how do you do the same for the ARM (M3) side of things?

Thanks.

over 7 years ago

0 ToddMullanix over 7 years ago

TI__Guru* 96960 points

I don't know of a specific SW_BREAKPOINT function. I'm checking with some other folks here. Meanwhile, other options are

"while(1);" and then change the PC to break out
Move parts of the code (via the linker file) into RAM so you have unlimited breakpoints
Add a function yourself called SW_BREAKPOINT. Set your one HW breakpoint there. Then sprinkle SW_BREAKPOINT around as needed.
Get rid of the "run to main" breakpoint. In CCS, Tools->Debugger Options->Auto Run and Load. 2 is better than 1:)
Get rid of the "enable CIO functions" breakpoint. In CCS, Tools->Debugger Options->Program/Memory Load Options. Up to 3!

Todd

0 Steve Goodrich over 7 years ago in reply to ToddMullanix

Intellectual 515 points

Thanks, Todd. I'd done a variant of the "while (1);" I killed the other tool-based breakpoints, and that should help.

Here's the rest of the solution I put together:

// Software Breakpoints
#if defined(__TI_ARM_V7M3__)
#define BKPT do { __asm (" bkpt #0"); } while (0) // ARM Cortex M3 Software Breakpoint
#elif defined(__TMS320C28XX__)
#define BKPT do { asm (" ESTOP0"); } while (0) // C28xx Software Breakpoint - stop here
#define BKPTN do { asm (" ESTOP1"); } while (0) // C28xx Software Breakpoint - stop at next instruction
#endif // #if defined(__TI_ARM_V7M3__) || defined(__TMS320C28XX__)

0 ToddMullanix over 7 years ago in reply to Steve Goodrich

TI__Guru* 96960 points

Hi Steve,

Someone here just pointed me to the ESTOP0 and ESTOP1 also on the C2000. Do you need the while(0) after that though?

Todd

0 Steve Goodrich over 7 years ago in reply to ToddMullanix

Intellectual 515 points

It's a C language construct that enables macros to work within "if" statements, both with and without braces:
stackoverflow.com/.../do-while-0-what-is-it-good-for

0 ToddMullanix over 7 years ago in reply to Steve Goodrich

TI__Guru* 96960 points

Ok. Can I close this out?

0 Steve Goodrich over 7 years ago in reply to ToddMullanix

Intellectual 515 points

Yes, I think we're good here.

0 Robert Cowsill over 7 years ago in reply to Steve Goodrich

Guru 16361 points

Eventually I hope the TI compiler team will implement a cross-platform intrinsic to do this, saving users from having to roll their own inline assembly.

I posted it as a feature request back in 2014: https://e2e.ti.com/support/development_tools/compiler/f/343/t/386496

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How do you insert a Software Breakpoint for F28M36 (C28 as well as M3)?