From cadafd4c3e67203aea80b99bd3839fc84ff7c17f Mon Sep 17 00:00:00 2001 From: Josh Blum Date: Fri, 11 Mar 2011 16:22:20 -0800 Subject: uhd: cleanup/tweaks on timed samples examples --- host/examples/tx_timed_samples.cpp | 58 +++++++++++++++++++++++--------------- 1 file changed, 36 insertions(+), 22 deletions(-) (limited to 'host/examples/tx_timed_samples.cpp') diff --git a/host/examples/tx_timed_samples.cpp b/host/examples/tx_timed_samples.cpp index f10d7e4ea..25a2c0e43 100644 --- a/host/examples/tx_timed_samples.cpp +++ b/host/examples/tx_timed_samples.cpp @@ -33,7 +33,6 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ std::string args; double seconds_in_future; size_t total_num_samps; - size_t samps_per_packet; double rate, freq; float ampl; @@ -42,9 +41,8 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ desc.add_options() ("help", "help message") ("args", po::value(&args)->default_value(""), "single uhd device address args") - ("secs", po::value(&seconds_in_future)->default_value(3), "number of seconds in the future to transmit") - ("nsamps", po::value(&total_num_samps)->default_value(1000), "total number of samples to transmit") - ("spp", po::value(&samps_per_packet)->default_value(1000), "number of samples per packet") + ("secs", po::value(&seconds_in_future)->default_value(1.5), "number of seconds in the future to transmit") + ("nsamps", po::value(&total_num_samps)->default_value(10000), "total number of samples to transmit") ("rate", po::value(&rate)->default_value(100e6/16), "rate of outgoing samples") ("freq", po::value(&freq)->default_value(0), "rf center frequency in Hz") ("ampl", po::value(&l)->default_value(float(0.3)), "amplitude of each sample") @@ -81,37 +79,53 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ std::cout << boost::format("Setting device timestamp to 0...") << std::endl; usrp->set_time_now(uhd::time_spec_t(0.0)); - //allocate data to send - std::vector > buff(samps_per_packet, std::complex(ampl, ampl)); + //allocate buffer with data to send + std::vector > buff(usrp->get_device()->get_max_send_samps_per_packet(), std::complex(ampl, ampl)); + //setup metadata for the first packet uhd::tx_metadata_t md; + md.start_of_burst = false; + md.end_of_burst = false; + md.has_time_spec = true; md.time_spec = uhd::time_spec_t(seconds_in_future); - //send the data in multiple packets - size_t num_packets = (total_num_samps+samps_per_packet-1)/samps_per_packet; - for (size_t i = 0; i < num_packets; i++){ + //the first call to send() will block this many seconds before sending: + double timeout = seconds_in_future + 0.1; //timeout (delay before transmit + padding) - //setup the metadata flags per fragment - md.start_of_burst = (i == 0); //only first packet has SOB - md.end_of_burst = (i == num_packets-1); //only last packet has EOB - md.has_time_spec = (i == 0); //only first packet has time + size_t num_acc_samps = 0; //number of accumulated samples + while(num_acc_samps < total_num_samps){ + size_t samps_to_send = std::min(total_num_samps - num_acc_samps, buff.size()); - size_t samps_to_send = std::min(total_num_samps - samps_per_packet*i, samps_per_packet); + //ensure the the last packet has EOB set + md.end_of_burst = samps_to_send <= buff.size(); - //send the entire packet (driver fragments internally) + //send a single packet size_t num_tx_samps = usrp->get_device()->send( &buff.front(), samps_to_send, md, uhd::io_type_t::COMPLEX_FLOAT32, - uhd::device::SEND_MODE_FULL_BUFF, - //send will backup into the host this many seconds before sending: - seconds_in_future + 0.1 //timeout (delay before transmit + padding) + uhd::device::SEND_MODE_ONE_PACKET, timeout ); - 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; + + //use a small timeout for subsequent packets + timeout = 0.1; + + //do not use time spec for subsequent packets + md.has_time_spec = false; + + if (num_tx_samps < samps_to_send) std::cerr << "Send timeout..." << std::endl; + if(verbose) std::cout << boost::format("Sent packet: %u samples") % num_tx_samps << std::endl; + + num_acc_samps += num_tx_samps; } - //ensure that the buffers have flushed out to the device before deconstruction - boost::this_thread::sleep(boost::posix_time::seconds(1)); + std::cout << std::endl << "Waiting for async burst ACK... " << std::flush; + uhd::async_metadata_t async_md; + bool got_async_burst_ack = false; + //loop through all messages for the ACK packet (may have underflow messages in queue) + while (not got_async_burst_ack and usrp->get_device()->recv_async_msg(async_md, seconds_in_future)){ + got_async_burst_ack = (async_md.event_code == uhd::async_metadata_t::EVENT_CODE_BURST_ACK); + } + std::cout << (got_async_burst_ack? "success" : "fail") << std::endl; //finished std::cout << std::endl << "Done!" << std::endl << std::endl; -- cgit v1.2.3