On 08/04/2011 09:27 PM, Philip Ha wrote:
>> Would it be possible for you to send mails formatted correctly?
>>
>> Then the bug is somewhere in between the serial line and the test
>> application, including possibly in the driver.
>>
>> In order to know where it is, you should compute the latency at each
>> point on this path: when receiving the interrupt, when waking up the
>> task, etc...
>
> Hi Gilles,
>
> Sorry for the formatting, I am new to mailing lists.
>
> I have looked at the latency in the 16550A driver. The first thing
> the driver does in its ISR is to call rtdm_clock_read and store the
> resulting timestamp in a "struct rtser_event". The code I posted
> grabs this structure. If I use this as my timestamp I get the exact
> same timing results.
are you sure that the interrupt triggers as soon as you receive a
character, and not upon timeout when not receiving characters for some
time? After all, 100us is approximately the time to transmit one
character at 115200 bauds on the serial line.
--
Gilles.
_______________________________________________
Xenomai-help mailing list
[email protected]
https://mail.gna.org/listinfo/xenomai-help
