diff options
| author | Johnathan Corgan <johnathan@corganlabs.com> | 2017-10-05 15:04:28 -0700 |
|---|---|---|
| committer | Johnathan Corgan <johnathan@corganlabs.com> | 2017-10-05 15:04:28 -0700 |
| commit | 5a99d225cb5422b165c1af7cea484a3ad43a82a4 (patch) | |
| tree | 70bf3248dcbb93f7d0e47d15348156eaad2f36d4 | |
| parent | 2fec31c0919d001b7b53a994fae5cf2220251545 (diff) | |
| parent | 6b720a9ea43be61e210f645615392a388a0dfdd0 (diff) | |
Merge remote-tracking branch 'github/pr/1437'
| -rw-r--r-- | gr-uhd/include/gnuradio/uhd/usrp_source.h | 27 | ||||
| -rw-r--r-- | gr-uhd/lib/usrp_source_impl.cc | 12 | ||||
| -rw-r--r-- | gr-uhd/lib/usrp_source_impl.h | 4 |
3 files changed, 42 insertions, 1 deletions
diff --git a/gr-uhd/include/gnuradio/uhd/usrp_source.h b/gr-uhd/include/gnuradio/uhd/usrp_source.h index a0022b3876..027202e764 100644 --- a/gr-uhd/include/gnuradio/uhd/usrp_source.h +++ b/gr-uhd/include/gnuradio/uhd/usrp_source.h @@ -131,6 +131,33 @@ namespace gr { */ virtual void issue_stream_cmd(const ::uhd::stream_cmd_t &cmd) = 0; + /*! Configure the timeout value on the UHD recv() call + * + * This is an advanced use parameter. Changing the timeout value affects + * the latency of this block; a high timeout value can be more optimal + * for high-throughput applications (e.g., 1 second) and setting it to + * zero will have the best latency. Changing the timeout value may also + * be useful for custom FPGA modifications, where traffic might not be + * continuously streaming. + * For specialized high-performance use cases, twiddling these knobs may + * improve performance, but changes are not generally applicable. + * + * Note that UHD's recv() call may block until the timeout is over, which + * means this block might also block for up to the timeout value. + * + * \param timeout Timeout parameter in seconds. Cf. the UHD manual for + * uhd::rx_streamer::recv() for more details. A lower + * value will mean lower latency, but higher CPU load. + * \param one_packet If true, only receive one packet at a time. Cf. the + * UHD manual for uhd::rx_streamer::recv() for more + * details. A value of true will mean lower latency, + * but higher CPU load. + */ + virtual void set_recv_timeout( + const double timeout, + const bool one_packet=true + ) = 0; + /*! * Returns identifying information about this USRP's configuration. * Returns motherboard ID, name, and serial. diff --git a/gr-uhd/lib/usrp_source_impl.cc b/gr-uhd/lib/usrp_source_impl.cc index 034e8207ba..894a6d849b 100644 --- a/gr-uhd/lib/usrp_source_impl.cc +++ b/gr-uhd/lib/usrp_source_impl.cc @@ -71,6 +71,7 @@ namespace gr { args_to_io_sig(stream_args)), usrp_block_impl(device_addr, stream_args, ""), _recv_timeout(0.1), // seconds + _recv_one_packet(true), _tag_now(false), _issue_stream_cmd_on_start(issue_stream_cmd_on_start) { @@ -499,6 +500,15 @@ namespace gr { _tag_now = true; } + void + usrp_source_impl::set_recv_timeout( + const double timeout, + const bool one_packet + ) { + _recv_timeout = timeout; + _recv_one_packet = one_packet; + } + bool usrp_source_impl::start(void) { @@ -635,7 +645,7 @@ namespace gr { noutput_items, _metadata, _recv_timeout, - true /* one packet -> minimize latency */ + _recv_one_packet ); #else size_t num_samps = _dev->get_device()->recv diff --git a/gr-uhd/lib/usrp_source_impl.h b/gr-uhd/lib/usrp_source_impl.h index 2a53159f4e..d91fcec754 100644 --- a/gr-uhd/lib/usrp_source_impl.h +++ b/gr-uhd/lib/usrp_source_impl.h @@ -107,6 +107,7 @@ namespace gr { double set_lo_freq(double freq, const std::string &name, size_t chan); void issue_stream_cmd(const ::uhd::stream_cmd_t &cmd); + void set_recv_timeout(const double timeout, const bool one_packet); void flush(void); bool start(void); bool stop(void); @@ -126,7 +127,10 @@ namespace gr { #ifdef GR_UHD_USE_STREAM_API ::uhd::rx_streamer::sptr _rx_stream; size_t _samps_per_packet; + //! Timeout value for UHD's recv() call. Lower values mean lower latency. double _recv_timeout; + //! one_packet value for UHD's recv() call. 'true' is lower latency. + bool _recv_one_packet; #endif bool _tag_now; ::uhd::rx_metadata_t _metadata; |