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
Cpu_table.clicks_per_usec=25.
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
More information about the users
mailing list