[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Discuss-gnuradio] Delay of synchronization with PPS and UHD on USR
From: |
Juha Vierinen |
Subject: |
Re: [Discuss-gnuradio] Delay of synchronization with PPS and UHD on USRP2 |
Date: |
Sat, 22 May 2010 13:28:23 +0300 |
Could you check that the revisions of the USRP2s are the same. I
remember that the lower impedance in the rev 1 caused a pretty long
delay, but I think we fixed this. You could still look at the PPS
inputs with an oscilloscope probe and see what it looks like.
juha
On Sat, May 22, 2010 at 08:49, Josh Blum <address@hidden> wrote:
>
>>> When performing set_time_next_pps(...) you will want a sleep(1) prior to
>>> starting streaming. Because it could take as much as 1 second for the
>>> registers to latch the new time value.
>>
>> Yes, I have used sleep(1) commmand after I call set_time_next_pps()
>> function. The problem is that if I replace the mode "
>> STREAM_MODE_NUM_SAMPS_AND_DONE" with " STREAM_MODE_START_CONTINUOUS ",it
>> works. The rest of code is same.
>>
>
> Ok, just checking. I will try to reproduce the problem on monday.
>
> Two more questions:
>
> 1) When you used STREAM_MODE_NUM_SAMPS_AND_DONE, was there a time set, and
> if so, was it greater than the time set by set_time_next_pps?
>
> 2) When you used STREAM_MODE_START_CONTINUOUS, did the timestamps on the RX
> packets appear to be correct (after the time set by set_time_next_pps)?
>
> Thanks,
> -Josh
>
>
> _______________________________________________
> Discuss-gnuradio mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>