Hello - I am using 2 USRP E310 which I would like to frequency sync together. I am using a frequency generator which is generating a 1 PPS (1Hz sine wave) signal which I put through a power splitter to provide both USRPs with the same 1 PPS signal. I configured the rx_samples_to_file and tx_samples_from_file codes to allow me to use the external 1PPS signal by including the following into the code:
//sleep off if gpsdo detected and time next pps already set boost::this_thread::sleep(boost::posix_time::seconds(1)); //set time source if specified if (not time_source.empty()) usrp->set_time_source(time_source); //set the time at an unknown pps (will throw if no pps) std::cout << std::endl << "Attempt to detect the PPS and set the time..." << std::endl << std::endl; usrp->set_time_unknown_pps(uhd::time_spec_t(0.0)); std::cout << std::endl << "Success!" << std::endl << std::endl; When I run the rx_samples_to_file code with the above code included, I get a timeout error. I found that it was due to the line "usrp->set_time_unknown_pps(uhd::time_spec_t(0.0));" How can I get my two USRPs frequency synced without getting this error? Also, I saw that the 1 PPS signal provided to the USRP should be 3.3V - 5V. When I put a 1 PPS signal that strong on the spectrum analyzer, it shows a power output above +10 dBm. I know that the max RX input power is -15 dBm so I was hesitant to input a 1 PPS signal that strong. The 1 PPS signal I put into the sync port was 100 mV. Even with a 1 PPS signal with an output power of 100mV, I am still able to run the test_pps_input program successfully. So in summary, should I just send a 1 PPS signal with a power output above +10 dBm which equates to the 3.3V - 5V to the sync port even though I am able to run the test_pps_input program successfully with 100mV? How can I get the rx_samples_to_file program to run successfully without giving me a timeout error using the above lines of code? Thanks
_______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
