Is watchpoint work for DMA memory access???

[shenglin]

Hi, all,

I am try to use codewarrior watchpoint to mointor the memory access. I found it works for the core accessing the watched memory range, but can not works for the DMA accessing the watched memory range.

Is the watchpoint features can be used for DMA operation?

By the way, I am using MPC8548DS board.

Thanks for help!

Sheng

[ronco]

Hi Sheng,

No, Watchpoints do not work with DMA reads/writes because Watchpoints use debug registers in the Power Architecture processor (MPC8548 in your case) and these debug registers can monitor only the data traffice to/from the processor.  DMA read/write cycles occur entirely outside of the processor and are therefore not visible to the debug registers.  You will have to use some other tool, such as a logic analyzer, to capture these cycles.