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HW Timer shared between ecos RTC & hal_delay_us()


Can the same HW timer, used for ecos RTC be used by hal_delay_us()?

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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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