aboutsummaryrefslogtreecommitdiffstats
path: root/host/examples/rx_multi_samples.cpp
blob: 5c65f2fe8a512ad3f4b3814b906303f54b53f96b (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
168
169
170
171
172
173
174
175
176
177
178
179
180
//
// 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 <boost/thread.hpp>
#include <boost/algorithm/string.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, sync, subdev, channel_list;
    double seconds_in_future;
    size_t total_num_samps;
    double rate;

    //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>(&seconds_in_future)->default_value(1.5), "number of seconds in the future to receive")
        ("nsamps", po::value<size_t>(&total_num_samps)->default_value(10000), "total number of samples to receive")
        ("rate", po::value<double>(&rate)->default_value(100e6/16), "rate of incoming samples")
        ("sync", po::value<std::string>(&sync)->default_value("now"), "synchronization method: now, pps, mimo")
        ("subdev", po::value<std::string>(&subdev), "subdev spec (homogeneous across motherboards)")
        ("dilv", "specify to disable inner-loop verbose")
        ("channels", po::value<std::string>(&channel_list)->default_value("0"), "which channel(s) to use (specify \"0\", \"1\", \"0,1\", etc)")
    ;
    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 RX Multi Samples %s") % desc << std::endl;
        std::cout <<
        "    This is a demonstration of how to receive aligned data from multiple channels.\n"
        "    This example can receive from multiple DSPs, multiple motherboards, or both.\n"
        "    The MIMO cable or PPS can be used to synchronize the configuration. See --sync\n"
        "\n"
        "    Specify --subdev to select multiple channels per motherboard.\n"
        "      Ex: --subdev=\"0:A 0:B\" to get 2 channels on a Basic RX.\n"
        "\n"
        "    Specify --args to select multiple motherboards in a configuration.\n"
        "      Ex: --args=\"addr0=192.168.10.2, addr1=192.168.10.3\"\n"
        << 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::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args);

    //always select the subdevice first, the channel mapping affects the other settings
    if (vm.count("subdev")) usrp->set_rx_subdev_spec(subdev); //sets across all mboards

    std::cout << boost::format("Using Device: %s") % usrp->get_pp_string() << std::endl;

    //set the rx sample rate (sets across all channels)
    std::cout << boost::format("Setting RX Rate: %f Msps...") % (rate/1e6) << std::endl;
    usrp->set_rx_rate(rate);
    std::cout << boost::format("Actual RX Rate: %f Msps...") % (usrp->get_rx_rate()/1e6) << std::endl << std::endl;

    std::cout << boost::format("Setting device timestamp to 0...") << std::endl;
    if (sync == "now"){
        //This is not a true time lock, the devices will be off by a few RTT.
        //Rather, this is just to allow for demonstration of the code below.
        usrp->set_time_now(uhd::time_spec_t(0.0));
    }
    else if (sync == "pps"){
        usrp->set_time_source("external");
        usrp->set_time_unknown_pps(uhd::time_spec_t(0.0));
        boost::this_thread::sleep(boost::posix_time::seconds(1)); //wait for pps sync pulse
    }
    else if (sync == "mimo"){
        UHD_ASSERT_THROW(usrp->get_num_mboards() == 2);

        //make mboard 1 a slave over the MIMO Cable
        usrp->set_clock_source("mimo", 1);
        usrp->set_time_source("mimo", 1);

        //set time on the master (mboard 0)
        usrp->set_time_now(uhd::time_spec_t(0.0), 0);

        //sleep a bit while the slave locks its time to the master
        boost::this_thread::sleep(boost::posix_time::milliseconds(100));
    }

    //detect which channels to use
    std::vector<std::string> channel_strings;
    std::vector<size_t> channel_nums;
    boost::split(channel_strings, channel_list, boost::is_any_of("\"',"));
    for(size_t ch = 0; ch < channel_strings.size(); ch++){
        size_t chan = std::stoi(channel_strings[ch]);
        if(chan >= usrp->get_rx_num_channels()){
            throw std::runtime_error("Invalid channel(s) specified.");
        }
        else channel_nums.push_back(std::stoi(channel_strings[ch]));
    }

    //create a receive streamer
    //linearly map channels (index0 = channel0, index1 = channel1, ...)
    uhd::stream_args_t stream_args("fc32"); //complex floats
    stream_args.channels = channel_nums;
    uhd::rx_streamer::sptr rx_stream = usrp->get_rx_stream(stream_args);

    //setup streaming
    std::cout << std::endl;
    std::cout << boost::format(
        "Begin streaming %u samples, %f seconds in the future..."
    ) % total_num_samps % seconds_in_future << 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;
    stream_cmd.time_spec = uhd::time_spec_t(seconds_in_future);
    rx_stream->issue_stream_cmd(stream_cmd); //tells all channels to stream

    //meta-data will be filled in by recv()
    uhd::rx_metadata_t md;

    //allocate buffers to receive with samples (one buffer per channel)
    const size_t samps_per_buff = rx_stream->get_max_num_samps();
    std::vector<std::vector<std::complex<float> > > buffs(
        usrp->get_rx_num_channels(), std::vector<std::complex<float> >(samps_per_buff)
    );

    //create a vector of pointers to point to each of the channel buffers
    std::vector<std::complex<float> *> buff_ptrs;
    for (size_t i = 0; i < buffs.size(); i++) buff_ptrs.push_back(&buffs[i].front());

    //the first call to recv() will block this many seconds before receiving
    double timeout = seconds_in_future + 0.1; //timeout (delay before receive + padding)

    size_t num_acc_samps = 0; //number of accumulated samples
    while(num_acc_samps < total_num_samps){
        //receive a single packet
        size_t num_rx_samps = rx_stream->recv(
            buff_ptrs, samps_per_buff, md, timeout
        );

        //use a small timeout for subsequent packets
        timeout = 0.1;

        //handle the error code
        if (md.error_code == uhd::rx_metadata_t::ERROR_CODE_TIMEOUT) break;
        if (md.error_code != uhd::rx_metadata_t::ERROR_CODE_NONE){
            throw std::runtime_error(str(boost::format(
                "Receiver error %s"
            ) % md.strerror()));
        }

        if(verbose) std::cout << boost::format(
            "Received packet: %u samples, %u full secs, %f frac secs"
        ) % num_rx_samps % md.time_spec.get_full_secs() % md.time_spec.get_frac_secs() << std::endl;

        num_acc_samps += num_rx_samps;
    }

    if (num_acc_samps < total_num_samps) std::cerr << "Receive timeout before all samples received..." << std::endl;

    //finished
    std::cout << std::endl << "Done!" << std::endl << std::endl;

    return EXIT_SUCCESS;
}