Read TCN-register in user space

[Björn Östby]

I'm currently using ELDK 3.0 (kernel 2.4.25) and a mpc823e trying to do some latency measurements for my final thesis project.

I'm wondering if there is any possibility to read the Timer Counter Register (TCN1) in user space. I have initially used gettimeofday(), which provides sufficient resolution (usec), but I suppose that solution probably adds on some kind of unknown context-switch latency. Does anyone have a clue on how to access this in user space? Could inline assembler or perhaps mmap() do the trick (I'm using C as programming language)?.


Regards,
Bjorn 




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