Clock ticks

Joel Sherrill <joel@OARcorp.com> joel.sherrill at OARcorp.com
Fri Jan 21 13:51:31 UTC 2005


Daniel Gustafsson wrote:
> We are using ERC32 with 20Mhz but don't get the right timing. What shall
> CONFIGURE_MICROSECONDS_PER_TICK be in our system?

Check the value of _CLOCK_SPEED when it is being set in boardinit.S
from this BSP.  It appears to default to 14 to indicate 14 Mhz.

--joel

> //Daniel
>  
> 
> 
>>-----Original Message-----
>>From: Joel Sherrill <joel at OARcorp.com> 
>>[mailto:joel.sherrill at OARcorp.com] 
>>Sent: Friday, January 21, 2005 1:21 PM
>>To: Ralf Corsepius
>>Cc: Daniel Gustafsson; RTEMS Users
>>Subject: Re: Clock ticks
>>
>>Ralf Corsepius wrote:
>>
>>>On Fri, 2005-01-21 at 10:52 +0100, Daniel Gustafsson wrote:
>>>
>>>
>>>>How do I inform Rtems 4.6.2 that I am running on a 20Mhz CPU.
>>>>
>>>>I've tried to alter MICRO_SECONDS_PER_TICK but i can't 
>>
>>figure out how it is
>>
>>>>done properly (correct value).
>>>
>>>It's highly BSP and target specific. Which target, which BSP are you
>>>using?
>>
>>If memory servers, they are on a SPARC/ERC32.  It should work
>>because the BSP will do math in the clock driver to convert the
>>configured value into the value used to program the timer.
>>
>>The constant you are using should be CONFIGURE_MICROSECONDS_PER_TICK
>>and it should be set BEFORE you include confdefs.h.
>>
>>--joel
>>
> 
> 
	

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
    Support Available             (256) 722-9985




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