An extra peice of information is that the block is instable even with 2 and three USRP2. This means sometimes it works and sometimes it producs no output.
Zohair wrote: > > Dear Josh, > > I have sorted out the PPS signal problem. It was the splitter that has the > problem and now I am able to output 5v signal from it. > > I tried to use an array of 2 and 3 usrp2 and it worked fine. However, the > block still doesn't work for my 4 USRP2. I see this error when I use them > all: > ***************************************** > Set time with unknown pps edge: > 1) set times next pps (race condition) > 2) catch seconds rollover at pps edge > 3) set times next pps (synchronously) > Times set to 0 successfully! <<== note: these are printed if there's > no time deviation > Times set to 0 successfully! > Times set to 0 successfully! > gr_block_executor: source <gr_block uhd mimo source (1)> produced no > output. We're marking it DONE. > *************************************** > > Any help, please? > > Thanks again, > > Zohair > > > > Josh Blum-2 wrote: >> >> The errors below confirm my suspicion that the sync at next pps is not >> activated. The "Set time with unknown pps edge" routine will write time >> zero into your devices. However, the times all read 102.xxx seconds >> after the sync. I assume your powered them up at nearly the same time >> (on a power switch) approximately 102 seconds prior to running the code >> below. :-) >> >> 1.5 volts is too low for the pps. You need 5v cmos ideally. It may be >> possible that the load on the pps is too high. What is the pps level >> before the splitter? I recommend an active splitter that gives you 5v >> cmos out. >> >> Since we have narrowed the problem down you can test this with a single >> usrp2.To debug this, take one usrp2, attach pps and ref with no >> splitter, modify the examples/rx_timed_example to set the clock config, >> and set the time at next pps, sleep(1). Readback the time and see if it >> is expected. >> >> Thank you, >> -Josh >> >> On 07/21/2010 04:54 AM, Zohair wrote: >>> >>> Dear Josh, >>> I have used another set of 4 USRP2's to test my program. Unlike the >>> error I >>> see when using my old set I receive this output. >>> >>> Current recv sock buff size: 50000000 bytes >>> Current send sock buff size: 50000000 bytes >>> Current recv sock buff size: 50000000 bytes >>> Current send sock buff size: 50000000 bytes >>> Current recv sock buff size: 50000000 bytes >>> Current send sock buff size: 50000000 bytes >>> Current recv sock buff size: 50000000 bytes >>> Current send sock buff size: 50000000 bytes >>> Using: Flex 2400 MIMO B RX (0x0027) >>> Using: Flex 2400 MIMO B TX (0x002b) >>> Using: Flex 2400 MIMO B RX (0x0027) >>> Using: Flex 2400 MIMO B TX (0x002b) >>> Using: Flex 2400 MIMO B RX (0x0027) >>> Using: Flex 2400 MIMO B TX (0x002b) >>> Using: Flex 2400 MIMO B RX (0x0027) >>> Using: Flex 2400 MIMO B TX (0x002b) >>> RX samples per packet: 362 >>> TX samples per packet: 363 >>> Recv pirate num frames: 33967 >>> Set time with unknown pps edge: >>> 1) set times next pps (race condition) >>> 2) catch seconds rollover at pps edge >>> 3) set times next pps (synchronously) >>> Error: time deviation between board 1 and board 0. >>> Board 0 time is 102.881714 seconds. >>> Board 1 time is 102.838705 seconds. >>> >>> Error: time deviation between board 2 and board 0. >>> Board 0 time is 102.883991 seconds. >>> Board 2 time is 102.798313 seconds. >>> >>> Error: time deviation between board 3 and board 0. >>> Board 0 time is 102.889212 seconds. >>> Board 3 time is 102.832728 seconds. >>> >>> >>>>>> Done >>> >>> The differnce here is that the program keeps running and I dont receive >>> the >>> "gr_block_executor: source<gr_block uhd mimo source (6)> produced no >>> output. We're marking it DONE." >>> >>> Also, attached are the photos of the clock and the pps signal at the >>> output >>> of the splitters at the input of the USRPs. >>> >>> Any help with this please? I also want to know if my old set of USRPs >>> has a >>> problem. >>> >>> Best regards, >>> >>> Zohair >>> >>> Josh Blum-2 wrote: >>>> >>>> I pushed some changes to the uhd master that will check the deviation >>>> on >>>> the times between boards. This should help you to debug your setup. If >>>> you see an error message like the following, then you may have an issue >>>> with the configuration. In the following example, I disconnected the >>>> PPS >>>> on one of the boards. This is the result: >>>> >>>> Set time with unknown pps edge: >>>> 1) set times next pps (race condition) >>>> 2) catch seconds rollover at pps edge >>>> 3) set times next pps (synchronously) >>>> Error: time deviation between board 1 and board 0. >>>> Board 0 time is 0.008782 seconds. >>>> Board 1 time is 65.009945 seconds. >>>> >>>> gr_block_executor: source<gr_block uhd mimo source (3)> produced no >>>> output. We're marking it DONE. >>>> >>>> -Josh >>>> >>>> On 07/12/2010 07:14 AM, Zohair M. Abu Shaban wrote: >>>>> >>>>> >>>>> Dear Josh, >>>>> >>>>> Thanks for the info provided and the help. >>>>> >>>>> I >>>>> have 4 USRP2 boards, 2 separate function generators and 2 splitters to >>>>> supply PPS and REF clock with specs as in the FAQ page. For testing >>>>> only, I used a VRT version of the firmware that my colleague modified >>>>> to send the REF clock to the debug pins, and I was able to see that >>>>> the >>>>> ref clocks are synchronized. >>>>> >>>>> I tried to work with 2 channels, 3 channels and 4 channels and wasn't >>>>> lucky enough to get something working. >>>>> >>>>> I am also interested to know if anybody has tried the MIMO block and >>>>> got >>>>> it working/not working. >>>>> >>>>> Best regards, >>>>> zohair >>>>> >>>>> >>>>> >>>>> >>>>>> Date: Fri, 9 Jul 2010 09:18:24 -0700 >>>>>> From: [email protected] >>>>>> To: [email protected] >>>>>> CC: [email protected] >>>>>> Subject: Re: [Discuss-gnuradio] UHD Announcement - July 6th 2010 >>>>>> >>>>>> >>>>>>> 3) set times next pps (synchronously) >>>>>>> gr_block_executor: source<gr_block uhd mimo source (1)> produced >>>>>>> no >>>>>>> output. We're marking it DONE. >>>>>>> >>>>>> >>>>>> This tells me that the alignment buffer is not finding a common >>>>>> timestamp among the 4 channels or one or more channels is not >>>>>> streaming >>>>>> (perhaps a timestamp/setup issue). What does your setup look like, is >>>>>> there a common pps and common reference split 4X to each usrp2? I >>>>>> forgot >>>>>> to add it to the notes but each device should have a common ref and >>>>>> pps >>>>>> attached to its front panel. Also, can you try to run with just two >>>>>> usrp2 to simplify the problem, does it work with 2 but not 3, 3 but >>>>>> not >>>>>> 4...? >>>>>> >>>>>>> >>>>>>> Sometimes I also receive these errors that disappear when I power >>>>>>> cycle >>>>>>> the USRP2's: >>>>>>> >>>>>>> Error (usrp2 recv pirate loop): bad vrt header or unsupported packet >>>>>>> type >>>>>>> Error (usrp2 recv pirate loop): assertion failed: >>>>>>> if_packet_info.has_tsi >>>>>>> and if_packet_info.has_tsf >>>>>>> in void >>>>>>> usrp2_impl::io_impl::recv_pirate_loop(boost::shared_ptr<uhd::transport::zero_copy_if>, >>>>>>> boost::shared_ptr<usrp2_mboard_impl>, size_t) >>>>>>> at /home/dave/uhd/host/lib/usrp/usrp2/io_impl.cpp:97 >>>>>>> >>>>>> >>>>>> Because the previous run did not exit cleanly and stop streaming, the >>>>>> recv loop is catching the middle of a packet from the previous run. >>>>>> This >>>>>> is safe to ignore. >>>>>> >>>>>> -Josh >>>>> >>>>> _________________________________________________________________ >>>>> http://clk.atdmt.com/UKM/go/197222280/direct/01/ >>>>> We want to hear all your funny, exciting and crazy Hotmail stories. >>>>> Tell >>>>> us now >>>> >>>> _______________________________________________ >>>> Discuss-gnuradio mailing list >>>> [email protected] >>>> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>> >>>> >>> http://old.nabble.com/file/p29224741/20100720119.JPG 20100720119.JPG >>> http://old.nabble.com/file/p29224741/20100720120.jpg 20100720120.jpg >> >> _______________________________________________ >> Discuss-gnuradio mailing list >> [email protected] >> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> > > -- View this message in context: http://old.nabble.com/UHD-Announcement---July-6th-2010-tp29091756p29268907.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
