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HW Timer shared between ecos RTC & hal_delay_us()
- From: "Michael Anburaj" <embeddedeng at hotmail dot com>
- To: ecos-discuss at sources dot redhat dot com
- Date: Thu, 10 Jul 2003 02:14:11 +0000
- Subject: [ECOS] HW Timer shared between ecos RTC & hal_delay_us()
- Bcc:
Can the same HW timer, used for ecos RTC be used by hal_delay_us()?
--- End of short description ---------
--- Long description ---------
When I looked at different platform implementations of different
architectures, I see most of the platforms using a different, separate HW
timer for hal_delay_us() in polling mode. And some platforms (EDB7xxx & MIPS
platforms) share the same ecos RTC HW timer. It should not affect when
Redboot is running, but what will happen when ecos is running?
?Issue 1? with hal_delay_us() sharing the RTC HW timer:
Wheh this routine polls the shared HW timer Count register, the timer may
reach the ecos RTC period & would jump to the RTC Interrupt handler (may
stretch the delay produced by hal_delay_us()) . But, this shouldn?t be a
concern, because even if 2 separate HW timers are used for RTC &
hal_delay_us(), still the hal_delay_us() routine would get interrupted by
the RTC event.
So, Is there any other concern about ?hal_delay_us(), sharing the RTC HW
timer??
Thanks a lot,
-Mike.
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