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Diffstat (limited to 'host/examples/latency_test.cpp')
| -rw-r--r-- | host/examples/latency_test.cpp | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/host/examples/latency_test.cpp b/host/examples/latency_test.cpp new file mode 100644 index 000000000..596087d75 --- /dev/null +++ b/host/examples/latency_test.cpp @@ -0,0 +1,198 @@ +// +// Copyright 2010-2011 Ettus Research LLC +// +// This program is free software: you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program. If not, see <http://www.gnu.org/licenses/>. +// + +#include <uhd/utils/thread_priority.hpp> +#include <uhd/utils/safe_main.hpp> +#include <uhd/usrp/single_usrp.hpp> +#include <boost/program_options.hpp> +#include <boost/format.hpp> +#include <iostream> +#include <complex> + +namespace po = boost::program_options; + +int UHD_SAFE_MAIN(int argc, char *argv[]){ + uhd::set_thread_priority_safe(); + + //variables to be set by po + std::string args; + double wait_time; + size_t total_num_samps; + size_t samps_per_packet; + double rate, freq; + float ampl; + + //setup the program options + po::options_description desc("Allowed options"); + desc.add_options() + ("help", "help message") + ("args", po::value<std::string>(&args)->default_value(""), "single uhd device address args") + ("secs", po::value<double>(&wait_time)->default_value(0.1), "number of seconds in the future to transmit") + ("nsamps", po::value<size_t>(&total_num_samps)->default_value(100), "total number of samples to transmit") + ("spp", po::value<size_t>(&samps_per_packet)->default_value(1000), "number of samples per packet") + ("rate", po::value<double>(&rate)->default_value(100e6/4), "rate of outgoing samples") + ("freq", po::value<double>(&freq)->default_value(0), "rf center frequency in Hz") + ("ampl", po::value<float>(&l)->default_value(float(0.3)), "amplitude of each sample") + ("dilv", "specify to disable inner-loop verbose") + ; + po::variables_map vm; + po::store(po::parse_command_line(argc, argv, desc), vm); + po::notify(vm); + + //print the help message + if (vm.count("help")){ + std::cout << boost::format("Latency Test %s") % desc << std::endl; + return ~0; + } + + bool verbose = vm.count("dilv") == 0; + + //create a usrp device + std::cout << std::endl; + //std::cout << boost::format("Creating the usrp device with: %s...") % args << std::endl; + uhd::usrp::single_usrp::sptr sdev = uhd::usrp::single_usrp::make(args); + uhd::device::sptr dev = sdev->get_device(); + //std::cout << boost::format("Using Device: %s") % sdev->get_pp_string() << std::endl; + + //set the tx sample rate + sdev->set_tx_rate(rate); + std::cout << boost::format("Actual TX Rate: %f Msps...") % (sdev->get_tx_rate()/1e6) << std::endl; + + //set the rx sample rate + sdev->set_rx_rate(rate); + std::cout << boost::format("Actual RX Rate: %f Msps...") % (sdev->get_rx_rate()/1e6) << std::endl; + + //allocate data to send + std::vector<std::complex<float> > txbuff(samps_per_packet, std::complex<float>(ampl, ampl)); + + //allocate receive buffer + std::vector<std::complex<float> > rxbuff(samps_per_packet, std::complex<float>(ampl, ampl)); + + + int time_error = 0; + int ack = 0; + int underflow = 0; + int other = 0; + // ************************************************** + if(verbose) + std::cout << boost::format("Setting device timestamp to 0...") << std::endl; + sdev->set_time_now(uhd::time_spec_t(0.0)); + + //setup streaming + std::cout << std::endl; + if(verbose) + std::cout << boost::format( + "Begin receiving %u samples, %f seconds in the future..." + ) % total_num_samps % wait_time << std::endl; + + uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE); + stream_cmd.num_samps = total_num_samps; + stream_cmd.stream_now = false; + + double delta_t = 0.0001; + uhd::tx_metadata_t tx_md; + + size_t num_packets = (total_num_samps+samps_per_packet-1)/samps_per_packet; + + + double cur_time = 0.0; + sdev->set_time_now(uhd::time_spec_t(cur_time)); + + for(int j=0;j<100;j++) { + cur_time += wait_time; + stream_cmd.time_spec = uhd::time_spec_t(cur_time); + sdev->issue_stream_cmd(stream_cmd); + size_t num_acc_samps = 0; + uhd::rx_metadata_t rx_md; + while(num_acc_samps < total_num_samps){ + std::vector<std::complex<float> > rxbuff(dev->get_max_recv_samps_per_packet()); + size_t num_rx_samps = dev->recv( + &rxbuff.front(), rxbuff.size(), rx_md, + uhd::io_type_t::COMPLEX_FLOAT32, + uhd::device::RECV_MODE_ONE_PACKET + ); + + switch(rx_md.error_code){ + case uhd::rx_metadata_t::ERROR_CODE_NONE: + break; + case uhd::rx_metadata_t::ERROR_CODE_TIMEOUT: + if (num_acc_samps == 0) continue; + std::cout << boost::format + ("Got timeout before all samples received, possible packet loss, exiting loop...") << std::endl; + goto done_loop; + default: + std::cout << boost::format("Got error code 0x%x, exiting loop...") % rx_md.error_code << std::endl; + goto done_loop; + } + + if(verbose) std::cout << boost::format("Got packet: %u samples, %u full secs, %f frac secs") + % num_rx_samps % rx_md.time_spec.get_full_secs() % rx_md.time_spec.get_frac_secs() << std::endl; + + num_acc_samps += num_rx_samps; + } done_loop: + + if(verbose) std::cout << "Done receiving samps" << std::endl; + + for (size_t i = 0; i < num_packets; i++){ + //setup the metadata flags per fragment + tx_md.start_of_burst = (i == 0); //only first packet has SOB + tx_md.end_of_burst = (i == num_packets-1); //only last packet has EOB + tx_md.has_time_spec = (i == 0); //only first packet has time + + size_t samps_to_send = std::min(total_num_samps - samps_per_packet*i, samps_per_packet); + + //send the entire packet (driver fragments internally) + tx_md.time_spec = uhd::time_spec_t(cur_time+delta_t); + size_t num_tx_samps = dev->send + (&txbuff.front(), samps_to_send, tx_md, + uhd::io_type_t::COMPLEX_FLOAT32, + uhd::device::SEND_MODE_FULL_BUFF, + //send will backup into the host this many seconds before sending: + cur_time + delta_t + 0.1 //timeout (delay before transmit + padding) + ); + if (num_tx_samps < samps_to_send) std::cout << "Send timeout..." << std::endl; + if(verbose) + std::cout << std::endl << boost::format("Sent %d samples") % num_tx_samps << std::endl; + } + + uhd::async_metadata_t async_md; + if (not dev->recv_async_msg(async_md)){ + std::cout << boost::format + ("failed:\n Async message recv timed out.\n") << std::endl; + } else { + switch(async_md.event_code){ + case uhd::async_metadata_t::EVENT_CODE_TIME_ERROR : + time_error++; + break; + case uhd::async_metadata_t::EVENT_CODE_BURST_ACK : + ack++; + break; + case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW : + underflow++; + break; + default: + std::cout << boost::format + ("failed:\n Got unexpected event code 0x%x.\n") + % async_md.event_code << std::endl; + other++; + break; + } + } + } + std::cout << boost::format("ACK %d, UNDERFLOW %d, TIME_ERR %d, other %d") % ack + % underflow % time_error % other << std::endl; +} |