bsp_delay.... Question

[Joel Sherrill]

On 04/25/2011 11:49 AM, Thomas Doerfler wrote:
> Joel,
>
> without looking into the existing implementations: I would prefer to
> have nanoseconds as a base unit. If we think about systems in the 1GHz
> range, having a resolution of 1000 CPU clocks seems a bit outworn to me.
>
>
I agree with you Thomas but the existing implementations appear
to be in microseconds.  The common name is rtems_bsp_delay().

I wouldn't be opposed to adding an rtems_bsp_delay_nanoseconds()
to the set.

Jennifer and I were just looking at this.  The non-uniform nature
of this across the BSPs is confusing.

--joel
> wkr,
>
> Thomas.
>
> Am 25.04.2011 18:02, Joel Sherrill wrote:
>> Hi,
>>
>> Some BSPs have a bsp_delay method.  This is
>> a short duration spinner.  We think it is in
>> microsecond units but have no idea for sure
>> and it could vary by BSP.
>>
>> Jennifer and I would like to formalize the
>> definition of this.  And standardize it across
>> BSPs.  So if it is available, it is safer to
>> use. Questions are
>>
>> + OK to make a standard BSP method?
>> + Microseconds unit?
>>
>> If it is not available, what should the stub do?
>>
>> Should we have bsp_delay_usecs() and bsp_delay_nsecs?
>>
>> Comments appreciated!  Please
>>
>


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Joel Sherrill, Ph.D.             Director of Research&  Development
joel.sherrill at OARcorp.com        On-Line Applications Research
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