summaryrefslogtreecommitdiffstats
path: root/host/examples/latency_test.cpp
blob: 85ac73567bc089221bccd46254e2c948ff5c3da5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
//
// Copyright 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/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"
        << std::endl;
        return ~0;
    }

    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);

    //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);
        usrp->issue_stream_cmd(stream_cmd);

        /***************************************************************
         * Receive the requested packet
         **************************************************************/
        uhd::rx_metadata_t rx_md;
        size_t num_rx_samps = usrp->get_device()->recv(
            &buffer.front(), buffer.size(), rx_md,
            uhd::io_type_t::COMPLEX_FLOAT32,
            uhd::device::RECV_MODE_FULL_BUFF
        );

        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;

        /***************************************************************
         * 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 = usrp->get_device()->send(
            &buffer.front(), buffer.size(), tx_md,
            uhd::io_type_t::COMPLEX_FLOAT32,
            uhd::device::SEND_MODE_FULL_BUFF
        );
        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 usrp->get_device()->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;
        }
    }

    /***************************************************************
     * Print the summary
     **************************************************************/
    std::cout << boost::format("\nACK %d, UNDERFLOW %d, TIME_ERR %d, other %d")
        % ack % underflow % time_error % other << std::endl;
    return 0;
}