PIT initializing in MPC860

Leon Pollak leonp at plris.com
Thu Jan 22 16:34:59 UTC 2004

Hello to MPC860 gurus :-)

	I am stuck with the following small issue:
The file ../libcpu/powerpc/mpc8xx/clock/clock.c contains:

 pit_value = (rtems_configuration_get_microseconds_per_tick() *
               rtems_cpu_configuration_get_clicks_per_usec()) - 1 ;

and this value is calculated incorrectly in my case - MPC860 running at 25MHz 
I put Cpu_table.microseconds_per_tick=10000 (10ms per RTEMS clock) and 

This means that I incorrectly understand the meaning of 
Cpu_table.clicks_per_usec. As it is also used in several other places, I do 
not want to change it by deriving the required value from the formula in 
MPC860 manual.

I tried to find something in documentation, but was not able to find this 
Cpu_table, which is used in mpc8xx.

I shall be very thankful for clarification.
Leon M.Pollak
leonp at plris dot com

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