On 06/21/2013 09:41 AM, Tim Newman wrote: > Yes, bringing this back up. Back to the original topic. When I get this > FIFO ctrl error, the host is sending back an icmp port unreachable msg to > the usrp, I grab this using wireshark. >
Well if the app shutdown from the error. That could be the host's response to a stray packet coming from the USRP after the socket was closed. For example a UDP packet w/ a GPSDO NMEA message. So this ICMP error may not be indicative of anything. > All I'm doing is running "uhd_usrp_probe". I've tried with and without > adding the --args addr=<ip> parameter, same thing using both. > > I've debugged a bit, and increased the ACK_TIMEOUT in > usrp/usrp2/usrp2_fifo_ctrl.cpp from 0.5 to 10.0 and it literally just sits > at: > > Creating the usrp device with: ... > -- Opening a USRP2/N-Series device... > -- Current recv frame size: 1472 bytes > -- Current send frame size: 1472 bytes > <sits here for 10 seconds> > > Then spits out > RuntimeError: RuntimeError: fifo ctrl timed out looking for acks > > Again, there is a switch in between the USRP and the host. > Yup, definitely a lost packet. Its gone and more time isnt going to help. Question is, where is the packet lost? We have a control packet from host to switch, then switch to USRP. Then a response packet from USRP to switch, then switch to host. -josh > Tim > > > On Thu, Jun 13, 2013 at 12:27 AM, Sean Nowlan > <[email protected]>wrote: > >> I think 512 is the max value for N on N200/N210 hence 195kSps is minimum >> sample rate. >> >> >> Karan Talasila <[email protected]> wrote: >> >> @sean can you please tell me how you got minimum sampling rate for usrp >> N210 as 100*e6/512. I know that the sampling rate should be 100*e6/N where >> N is an integer. So N can be any integer even greater than 512 right. In >> that way, what is the minimum that the USRP accepts. what is maximum N that >> can be used. >> >> >> On Thu, Jun 13, 2013 at 6:20 AM, Sean Nowlan >> <[email protected]>wrote: >> >>> On 06/12/2013 08:49 PM, Marcus D. Leech wrote: >>> >>>> On 06/12/2013 08:29 PM, Sean Nowlan wrote: >>>> >>>>> >>>>> The minimum "reasonable" sample rate I've used is 2e5 (100e6/2e5 = >>>>> 500). I think 100e6/512 = 195312.5 is the smallest supported rate. >>>>> >>>>> Yup, sorry, you're right. I tend to pick values that are valid for >>>> both 64Msps and 100Msps master clock rates, since I write apps that need to >>>> be reasonably >>>> agnostic with respect to hardware. >>>> >>>> >>>> Ah, makes sense. >>> >>> >>>> >>>> >>> >>> ______________________________**_________________ >>> Discuss-gnuradio mailing list >>> [email protected] >>> https://lists.gnu.org/mailman/**listinfo/discuss-gnuradio<https://lists.gnu.org/mailman/listinfo/discuss-gnuradio> >>> >> >> >> >> -- >> Regards >> Karan Talasila >> >> _______________________________________________ >> Discuss-gnuradio mailing list >> [email protected] >> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> > > > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
