PocketMatrix

I'm writing a small assembly routine to read the clock counter (CCNT) from
my Pocket PC (PXA270 processor).

I used the following assembly code:
MRC p14, 0, R0, c1, c1, 0

Unfortunately, all I got was a constant number (86334131) while it
was supposed to change over time.

What's wrong? Please help me.

How have you configured the PMNC register? If you haven't configured it then the clock counter is probably not turned on and you need to set the bottom bit of the PMNC register.

Look at chapter 8 (especially page 104) of <a href="ftp://download.intel.com/design/intelxscale/27347302.pdf">this</a>.