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//
// Copyright 2011 Ettus Research LLC
//
// SPDX-License-Identifier: GPL-3.0
//
#include <uhd/utils/thread.hpp>
#include <uhd/utils/safe_main.hpp>
#include <uhd/usrp/multi_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;
size_t nsamps;
double rate;
double rtt;
size_t nruns;
//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")
("nsamps", po::value<size_t>(&nsamps)->default_value(100), "number of samples per run")
("nruns", po::value<size_t>(&nruns)->default_value(1000), "number of tests to perform")
("rtt", po::value<double>(&rtt)->default_value(0.001), "delay between receive and transmit (seconds)")
("rate", po::value<double>(&rate)->default_value(100e6/4), "sample rate for receive and transmit (sps)")
("verbose", "specify to enable 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("UHD - Latency Test %s") % desc << std::endl;
std::cout <<
" Latency test receives a packet at time t,\n"
" and tries to send a packet at time t + rtt,\n"
" where rtt is the round trip time sample time\n"
" from device to host and back to the device.\n"
" This can be used to test latency between UHD and the device.\n"
" If the value rtt is chosen too small, the transmit packet will.\n"
" arrive too late at the device indicate an error.\n"
" The smallest value of rtt that does not indicate an error is an\n"
" approximation for the time it takes for a sample packet to\n"
" go to UHD and back to the device."
<< std::endl;
return EXIT_SUCCESS;
}
bool verbose = vm.count("verbose") != 0;
//create a usrp device
std::cout << std::endl;
//std::cout << boost::format("Creating the usrp device with: %s...") % args << std::endl;
uhd::usrp::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args);
//std::cout << boost::format("Using Device: %s") % usrp->get_pp_string() << std::endl;
usrp->set_time_now(uhd::time_spec_t(0.0));
//set the tx sample rate
usrp->set_tx_rate(rate);
std::cout
<< boost::format("Actual TX Rate: %f Msps...")
% (usrp->get_tx_rate()/1e6)
<< std::endl;
//set the rx sample rate
usrp->set_rx_rate(rate);
std::cout
<< boost::format("Actual RX Rate: %f Msps...")
% (usrp->get_rx_rate()/1e6)
<< std::endl;
//allocate a buffer to use
std::vector<std::complex<float> > buffer(nsamps);
//create RX and TX streamers
uhd::stream_args_t stream_args("fc32"); //complex floats
uhd::rx_streamer::sptr rx_stream = usrp->get_rx_stream(stream_args);
uhd::tx_streamer::sptr tx_stream = usrp->get_tx_stream(stream_args);
//initialize result counts
int time_error = 0;
int ack = 0;
int underflow = 0;
int other = 0;
for(size_t nrun = 0; nrun < nruns; nrun++){
/***************************************************************
* Issue a stream command some time in the near future
**************************************************************/
uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE);
stream_cmd.num_samps = buffer.size();
stream_cmd.stream_now = false;
stream_cmd.time_spec = usrp->get_time_now() + uhd::time_spec_t(0.01);
rx_stream->issue_stream_cmd(stream_cmd);
/***************************************************************
* Receive the requested packet
**************************************************************/
uhd::rx_metadata_t rx_md;
size_t num_rx_samps = rx_stream->recv(
&buffer.front(), buffer.size(), rx_md
);
if (verbose) {
std::cout << boost::format(
"Run %d: Got packet: %u samples, %u full secs, %f frac secs"
)
% nrun
% num_rx_samps
% rx_md.time_spec.get_full_secs()
% rx_md.time_spec.get_frac_secs()
<< std::endl;
} else {
std::cout << "." << std::flush;
}
/***************************************************************
* Transmit a packet with delta time after received packet
**************************************************************/
uhd::tx_metadata_t tx_md;
tx_md.start_of_burst = true;
tx_md.end_of_burst = true;
tx_md.has_time_spec = true;
tx_md.time_spec = rx_md.time_spec + uhd::time_spec_t(rtt);
size_t num_tx_samps = tx_stream->send(
&buffer.front(), buffer.size(), tx_md
);
if (verbose) {
std::cout
<< boost::format("Sent %d samples") % num_tx_samps
<< std::endl;
}
/***************************************************************
* Check the async messages for result
**************************************************************/
uhd::async_metadata_t async_md;
if (not tx_stream->recv_async_msg(async_md)){
std::cout << boost::format("failed:\n Async message recv timed out.\n") << std::endl;
continue;
}
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::cerr << boost::format(
"failed:\n Got unexpected event code 0x%x.\n"
) % async_md.event_code << std::endl;
other++;
break;
}
}
while (true) {
uhd::async_metadata_t async_md;
if (not tx_stream->recv_async_msg(async_md)) {
break;
}
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::cerr << boost::format(
"failed:\n Got unexpected event code 0x%x.\n"
) % async_md.event_code << std::endl;
other++;
break;
}
}
if (!verbose) {
std::cout << std::endl;
}
/***************************************************************
* Print the summary
**************************************************************/
std::cout << "Summary\n"
<< "================\n"
<< "Number of runs: " << nruns << std::endl
<< "RTT value tested: " << (rtt*1e3) << " ms" << std::endl
<< "ACKs received: " << ack << "/" << nruns << std::endl
<< "Underruns: " << underflow << std::endl
<< "Late packets: " << time_error << std::endl
<< "Other errors: " << other << std::endl
<< std::endl;
return EXIT_SUCCESS;
}
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