diff options
Diffstat (limited to 'host/lib/usrp/usrp1/io_impl.cpp')
| -rw-r--r-- | host/lib/usrp/usrp1/io_impl.cpp | 710 |
1 files changed, 710 insertions, 0 deletions
diff --git a/host/lib/usrp/usrp1/io_impl.cpp b/host/lib/usrp/usrp1/io_impl.cpp new file mode 100644 index 000000000..8940a92bb --- /dev/null +++ b/host/lib/usrp/usrp1/io_impl.cpp @@ -0,0 +1,710 @@ +// +// Copyright 2010-2012 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 "validate_subdev_spec.hpp" +#define SRPH_DONT_CHECK_SEQUENCE +#include "../../transport/super_recv_packet_handler.hpp" +#define SSPH_DONT_PAD_TO_ONE +#include "../../transport/super_send_packet_handler.hpp" +#include "usrp1_calc_mux.hpp" +#include "usrp1_impl.hpp" +#include <uhd/utils/msg.hpp> +#include <uhd/utils/tasks.hpp> +#include <uhd/utils/safe_call.hpp> +#include <uhd/transport/bounded_buffer.hpp> +#include <boost/math/special_functions/sign.hpp> +#include <boost/math/special_functions/round.hpp> +#include <boost/thread/thread.hpp> +#include <boost/bind.hpp> +#include <boost/format.hpp> +#include <boost/make_shared.hpp> + +#define bmFR_RX_FORMAT_SHIFT_SHIFT 0 +#define bmFR_RX_FORMAT_WIDTH_SHIFT 4 +#define bmFR_TX_FORMAT_16_IQ 0 +#define bmFR_RX_FORMAT_WANT_Q (0x1 << 9) +#define FR_RX_FREQ_0 34 +#define FR_RX_FREQ_1 35 +#define FR_RX_FREQ_2 36 +#define FR_RX_FREQ_3 37 +#define FR_INTERP_RATE 32 +#define FR_DECIM_RATE 33 +#define FR_RX_MUX 38 +#define FR_TX_MUX 39 +#define FR_TX_FORMAT 48 +#define FR_RX_FORMAT 49 +#define FR_TX_SAMPLE_RATE_DIV 0 +#define FR_RX_SAMPLE_RATE_DIV 1 +#define GS_TX_UNDERRUN 0 +#define GS_RX_OVERRUN 1 +#define VRQ_GET_STATUS 0x80 + +using namespace uhd; +using namespace uhd::usrp; +using namespace uhd::transport; + +static const size_t alignment_padding = 512; + +/*********************************************************************** + * Helper struct to associate an offset with a buffer + **********************************************************************/ +struct offset_send_buffer{ + offset_send_buffer(void){ + /* NOP */ + } + + offset_send_buffer(managed_send_buffer::sptr buff, size_t offset = 0): + buff(buff), offset(offset) + { + /* NOP */ + } + + //member variables + managed_send_buffer::sptr buff; + size_t offset; /* in bytes */ +}; + +/*********************************************************************** + * Reusable managed send buffer to handle aligned commits + **********************************************************************/ +class offset_managed_send_buffer : public managed_send_buffer{ +public: + typedef boost::function<void(offset_send_buffer&, offset_send_buffer&, size_t)> commit_cb_type; + offset_managed_send_buffer(const commit_cb_type &commit_cb): + _commit_cb(commit_cb) + { + /* NOP */ + } + + void release(void){ + this->_commit_cb(_curr_buff, _next_buff, size()); + } + + sptr get_new( + offset_send_buffer &curr_buff, + offset_send_buffer &next_buff + ){ + _curr_buff = curr_buff; + _next_buff = next_buff; + return make(this, + _curr_buff.buff->cast<char *>() + _curr_buff.offset, + _curr_buff.buff->size() - _curr_buff.offset + ); + } + +private: + offset_send_buffer _curr_buff, _next_buff; + commit_cb_type _commit_cb; +}; + +/*********************************************************************** + * BS VRT packer/unpacker functions (since samples don't have headers) + **********************************************************************/ +static void usrp1_bs_vrt_packer( + boost::uint32_t *, + vrt::if_packet_info_t &if_packet_info +){ + if_packet_info.num_header_words32 = 0; + if_packet_info.num_packet_words32 = if_packet_info.num_payload_words32; +} + +static void usrp1_bs_vrt_unpacker( + const boost::uint32_t *, + vrt::if_packet_info_t &if_packet_info +){ + if_packet_info.packet_type = vrt::if_packet_info_t::PACKET_TYPE_DATA; + if_packet_info.num_payload_words32 = if_packet_info.num_packet_words32; + if_packet_info.num_payload_bytes = if_packet_info.num_packet_words32*sizeof(boost::uint32_t); + if_packet_info.num_header_words32 = 0; + if_packet_info.packet_count = 0; + if_packet_info.sob = false; + if_packet_info.eob = false; + if_packet_info.has_sid = false; + if_packet_info.has_cid = false; + if_packet_info.has_tsi = false; + if_packet_info.has_tsf = false; + if_packet_info.has_tlr = false; +} + +/*********************************************************************** + * IO Implementation Details + **********************************************************************/ +struct usrp1_impl::io_impl{ + io_impl(zero_copy_if::sptr data_transport): + data_transport(data_transport), + curr_buff(offset_send_buffer(data_transport->get_send_buff())), + omsb(boost::bind(&usrp1_impl::io_impl::commit_send_buff, this, _1, _2, _3)) + { + /* NOP */ + } + + ~io_impl(void){ + UHD_SAFE_CALL(flush_send_buff();) + } + + zero_copy_if::sptr data_transport; + + //wrapper around the actual send buffer interface + //all of this to ensure only aligned lengths are committed + //NOTE: you must commit before getting a new buffer + //since the vrt packet handler obeys this, we are ok + offset_send_buffer curr_buff; + offset_managed_send_buffer omsb; + void commit_send_buff(offset_send_buffer&, offset_send_buffer&, size_t); + void flush_send_buff(void); + managed_send_buffer::sptr get_send_buff(double timeout){ + //try to get a new managed buffer with timeout + offset_send_buffer next_buff(data_transport->get_send_buff(timeout)); + if (not next_buff.buff.get()) return managed_send_buffer::sptr(); /* propagate timeout here */ + + //make a new managed buffer with the offset buffs + return omsb.get_new(curr_buff, next_buff); + } + + task::sptr vandal_task; + boost::system_time last_send_time; +}; + +/*! + * Perform an actual commit on the send buffer: + * Copy the remainder of alignment to the next buffer. + * Commit the current buffer at multiples of alignment. + */ +void usrp1_impl::io_impl::commit_send_buff( + offset_send_buffer &curr, + offset_send_buffer &next, + size_t num_bytes +){ + //total number of bytes now in the current buffer + size_t bytes_in_curr_buffer = curr.offset + num_bytes; + + //calculate how many to commit and remainder + size_t num_bytes_remaining = bytes_in_curr_buffer % alignment_padding; + size_t num_bytes_to_commit = bytes_in_curr_buffer - num_bytes_remaining; + + //copy the remainder into the next buffer + std::memcpy( + next.buff->cast<char *>() + next.offset, + curr.buff->cast<char *>() + num_bytes_to_commit, + num_bytes_remaining + ); + + //update the offset into the next buffer + next.offset += num_bytes_remaining; + + //commit the current buffer + curr.buff->commit(num_bytes_to_commit); + + //store the next buffer for the next call + curr_buff = next; +} + +/*! + * Flush the current buffer by padding out to alignment and committing. + */ +void usrp1_impl::io_impl::flush_send_buff(void){ + //calculate the number of bytes to alignment + size_t bytes_to_pad = (-1*curr_buff.offset)%alignment_padding; + + //send at least alignment_padding to guarantee zeros are sent + if (bytes_to_pad == 0) bytes_to_pad = alignment_padding; + + //get the buffer, clear, and commit (really current buffer) + managed_send_buffer::sptr buff = this->get_send_buff(.1); + if (buff.get() != NULL){ + std::memset(buff->cast<void *>(), 0, bytes_to_pad); + buff->commit(bytes_to_pad); + } +} + +/*********************************************************************** + * Initialize internals within this file + **********************************************************************/ +void usrp1_impl::io_init(void){ + + _io_impl = UHD_PIMPL_MAKE(io_impl, (_data_transport)); + + //init as disabled, then call the real function (uses restore) + this->enable_rx(false); + this->enable_tx(false); + rx_stream_on_off(false); + tx_stream_on_off(false); + _io_impl->flush_send_buff(); + + //create a new vandal thread to poll xerflow conditions + _io_impl->vandal_task = task::make(boost::bind( + &usrp1_impl::vandal_conquest_loop, this + )); +} + +void usrp1_impl::rx_stream_on_off(bool enb){ + this->restore_rx(enb); + //drain any junk in the receive transport after stop streaming command + while(not enb and _data_transport->get_recv_buff().get() != NULL){ + /* NOP */ + } +} + +void usrp1_impl::tx_stream_on_off(bool enb){ + _io_impl->last_send_time = boost::get_system_time(); + if (_tx_enabled and not enb) _io_impl->flush_send_buff(); + this->restore_tx(enb); +} + +/*! + * Casually poll the overflow and underflow registers. + * On an underflow, push an async message into the queue and print. + * On an overflow, interleave an inline message into recv and print. + * This procedure creates "soft" inline and async user messages. + */ +void usrp1_impl::vandal_conquest_loop(void){ + + //initialize the async metadata + async_metadata_t async_metadata; + async_metadata.channel = 0; + async_metadata.has_time_spec = true; + async_metadata.event_code = async_metadata_t::EVENT_CODE_UNDERFLOW; + + //initialize the inline metadata + rx_metadata_t inline_metadata; + inline_metadata.has_time_spec = true; + inline_metadata.error_code = rx_metadata_t::ERROR_CODE_OVERFLOW; + + //start the polling loop... + try{ while (not boost::this_thread::interruption_requested()){ + boost::uint8_t underflow = 0, overflow = 0; + + //shutoff transmit if it has been too long since send() was called + if (_tx_enabled and (boost::get_system_time() - _io_impl->last_send_time) > boost::posix_time::milliseconds(100)){ + this->tx_stream_on_off(false); + } + + //always poll regardless of enabled so we can clear the conditions + _fx2_ctrl->usrp_control_read( + VRQ_GET_STATUS, 0, GS_TX_UNDERRUN, &underflow, sizeof(underflow) + ); + _fx2_ctrl->usrp_control_read( + VRQ_GET_STATUS, 0, GS_RX_OVERRUN, &overflow, sizeof(overflow) + ); + + //handle message generation for xerflow conditions + if (_tx_enabled and underflow){ + async_metadata.time_spec = _soft_time_ctrl->get_time(); + _soft_time_ctrl->get_async_queue().push_with_pop_on_full(async_metadata); + UHD_MSG(fastpath) << "U"; + } + if (_rx_enabled and overflow){ + inline_metadata.time_spec = _soft_time_ctrl->get_time(); + _soft_time_ctrl->get_inline_queue().push_with_pop_on_full(inline_metadata); + UHD_MSG(fastpath) << "O"; + } + + boost::this_thread::sleep(boost::posix_time::milliseconds(50)); + }} + catch(const boost::thread_interrupted &){} //normal exit condition + catch(const std::exception &e){ + UHD_MSG(error) << "The vandal caught an unexpected exception " << e.what() << std::endl; + } +} + +/*********************************************************************** + * RX streamer wrapper that talks to soft time control + **********************************************************************/ +class usrp1_recv_packet_streamer : public sph::recv_packet_handler, public rx_streamer{ +public: + usrp1_recv_packet_streamer(const size_t max_num_samps, soft_time_ctrl::sptr stc){ + _max_num_samps = max_num_samps; + _stc = stc; + } + + size_t get_num_channels(void) const{ + return this->size(); + } + + size_t get_max_num_samps(void) const{ + return _max_num_samps; + } + + size_t recv( + const rx_streamer::buffs_type &buffs, + const size_t nsamps_per_buff, + uhd::rx_metadata_t &metadata, + const double timeout, + const bool one_packet + ){ + //interleave a "soft" inline message into the receive stream: + if (_stc->get_inline_queue().pop_with_haste(metadata)) return 0; + + size_t num_samps_recvd = sph::recv_packet_handler::recv( + buffs, nsamps_per_buff, metadata, timeout, one_packet + ); + + return _stc->recv_post(metadata, num_samps_recvd); + } + +private: + size_t _max_num_samps; + soft_time_ctrl::sptr _stc; +}; + +/*********************************************************************** + * TX streamer wrapper that talks to soft time control + **********************************************************************/ +class usrp1_send_packet_streamer : public sph::send_packet_handler, public tx_streamer{ +public: + usrp1_send_packet_streamer(const size_t max_num_samps, soft_time_ctrl::sptr stc, boost::function<void(bool)> tx_enb_fcn){ + _max_num_samps = max_num_samps; + this->set_max_samples_per_packet(_max_num_samps); + _stc = stc; + _tx_enb_fcn = tx_enb_fcn; + } + + size_t get_num_channels(void) const{ + return this->size(); + } + + size_t get_max_num_samps(void) const{ + return _max_num_samps; + } + + size_t send( + const tx_streamer::buffs_type &buffs, + const size_t nsamps_per_buff, + const uhd::tx_metadata_t &metadata, + const double timeout_ + ){ + double timeout = timeout_; //rw copy + _stc->send_pre(metadata, timeout); + + _tx_enb_fcn(true); //always enable (it will do the right thing) + size_t num_samps_sent = sph::send_packet_handler::send( + buffs, nsamps_per_buff, metadata, timeout + ); + + //handle eob flag (commit the buffer, //disable the DACs) + //check num samps sent to avoid flush on incomplete/timeout + if (metadata.end_of_burst and num_samps_sent == nsamps_per_buff){ + async_metadata_t metadata; + metadata.channel = 0; + metadata.has_time_spec = true; + metadata.time_spec = _stc->get_time(); + metadata.event_code = async_metadata_t::EVENT_CODE_BURST_ACK; + _stc->get_async_queue().push_with_pop_on_full(metadata); + _tx_enb_fcn(false); + } + + return num_samps_sent; + } + +private: + size_t _max_num_samps; + soft_time_ctrl::sptr _stc; + boost::function<void(bool)> _tx_enb_fcn; +}; + +/*********************************************************************** + * Properties callback methods below + **********************************************************************/ +void usrp1_impl::update_rx_subdev_spec(const uhd::usrp::subdev_spec_t &spec){ + + //sanity checking + validate_subdev_spec(_tree, spec, "rx"); + + _rx_subdev_spec = spec; //shadow + + //set the mux and set the number of rx channels + std::vector<mapping_pair_t> mapping; + BOOST_FOREACH(const subdev_spec_pair_t &pair, spec){ + const std::string conn = _tree->access<std::string>(str(boost::format( + "/mboards/0/dboards/%s/rx_frontends/%s/connection" + ) % pair.db_name % pair.sd_name)).get(); + mapping.push_back(std::make_pair(pair.db_name, conn)); + } + bool s = this->disable_rx(); + _iface->poke32(FR_RX_MUX, calc_rx_mux(mapping)); + this->restore_rx(s); +} + +void usrp1_impl::update_tx_subdev_spec(const uhd::usrp::subdev_spec_t &spec){ + + //sanity checking + validate_subdev_spec(_tree, spec, "tx"); + + _tx_subdev_spec = spec; //shadow + + //set the mux and set the number of tx channels + std::vector<mapping_pair_t> mapping; + BOOST_FOREACH(const subdev_spec_pair_t &pair, spec){ + const std::string conn = _tree->access<std::string>(str(boost::format( + "/mboards/0/dboards/%s/tx_frontends/%s/connection" + ) % pair.db_name % pair.sd_name)).get(); + mapping.push_back(std::make_pair(pair.db_name, conn)); + } + bool s = this->disable_tx(); + _iface->poke32(FR_TX_MUX, calc_tx_mux(mapping)); + this->restore_tx(s); +} + +void usrp1_impl::update_tick_rate(const double rate){ + //updating this variable should: + //update dboard iface -> it has a reference + //update dsp freq bounds -> publisher + _master_clock_rate = rate; +} + +uhd::meta_range_t usrp1_impl::get_rx_dsp_host_rates(void){ + meta_range_t range; + const size_t div = this->has_rx_halfband()? 2 : 1; + for (int rate = 256; rate >= 4; rate -= div){ + range.push_back(range_t(_master_clock_rate/rate)); + } + return range; +} + +uhd::meta_range_t usrp1_impl::get_tx_dsp_host_rates(void){ + meta_range_t range; + const size_t div = this->has_tx_halfband()? 2 : 1; + for (int rate = 256; rate >= 8; rate -= div){ + range.push_back(range_t(_master_clock_rate/rate)); + } + return range; +} + +double usrp1_impl::update_rx_samp_rate(size_t dspno, const double samp_rate){ + + const size_t div = this->has_rx_halfband()? 2 : 1; + const size_t rate = boost::math::iround(_master_clock_rate/this->get_rx_dsp_host_rates().clip(samp_rate, true)); + + if (rate < 8 and this->has_rx_halfband()) UHD_MSG(warning) << + "USRP1 cannot achieve decimations below 8 when the half-band filter is present.\n" + "The usrp1_fpga_4rx.rbf file is a special FPGA image without RX half-band filters.\n" + "To load this image, set the device address key/value pair: fpga=usrp1_fpga_4rx.rbf\n" + << std::endl; + + if (dspno == 0){ //only care if dsp0 is set since its homogeneous + bool s = this->disable_rx(); + _iface->poke32(FR_RX_SAMPLE_RATE_DIV, div - 1); + _iface->poke32(FR_DECIM_RATE, rate/div - 1); + this->restore_rx(s); + + //update the streamer if created + boost::shared_ptr<usrp1_recv_packet_streamer> my_streamer = + boost::dynamic_pointer_cast<usrp1_recv_packet_streamer>(_rx_streamer.lock()); + if (my_streamer.get() != NULL){ + my_streamer->set_samp_rate(_master_clock_rate / rate); + } + } + + return _master_clock_rate / rate; +} + +double usrp1_impl::update_tx_samp_rate(size_t dspno, const double samp_rate){ + + const size_t div = this->has_tx_halfband()? 4 : 2; //doubled for codec interp + const size_t rate = boost::math::iround(_master_clock_rate/this->get_tx_dsp_host_rates().clip(samp_rate, true)); + + if (dspno == 0){ //only care if dsp0 is set since its homogeneous + bool s = this->disable_tx(); + _iface->poke32(FR_TX_SAMPLE_RATE_DIV, div - 1); + _iface->poke32(FR_INTERP_RATE, rate/div - 1); + this->restore_tx(s); + + //update the streamer if created + boost::shared_ptr<usrp1_send_packet_streamer> my_streamer = + boost::dynamic_pointer_cast<usrp1_send_packet_streamer>(_tx_streamer.lock()); + if (my_streamer.get() != NULL){ + my_streamer->set_samp_rate(_master_clock_rate / rate); + } + } + + return _master_clock_rate / rate; +} + +void usrp1_impl::update_rates(void){ + const fs_path mb_path = "/mboards/0"; + this->update_tick_rate(_master_clock_rate); + BOOST_FOREACH(const std::string &name, _tree->list(mb_path / "rx_dsps")){ + _tree->access<double>(mb_path / "rx_dsps" / name / "rate" / "value").update(); + } + BOOST_FOREACH(const std::string &name, _tree->list(mb_path / "tx_dsps")){ + _tree->access<double>(mb_path / "tx_dsps" / name / "rate" / "value").update(); + } +} + +double usrp1_impl::update_rx_dsp_freq(const size_t dspno, const double freq_){ + + //correct for outside of rate (wrap around) + double freq = std::fmod(freq_, _master_clock_rate); + if (std::abs(freq) > _master_clock_rate/2.0) + freq -= boost::math::sign(freq)*_master_clock_rate; + + //calculate the freq register word (signed) + UHD_ASSERT_THROW(std::abs(freq) <= _master_clock_rate/2.0); + static const double scale_factor = std::pow(2.0, 32); + const boost::int32_t freq_word = boost::int32_t(boost::math::round((freq / _master_clock_rate) * scale_factor)); + + static const boost::uint32_t dsp_index_to_reg_val[4] = { + FR_RX_FREQ_0, FR_RX_FREQ_1, FR_RX_FREQ_2, FR_RX_FREQ_3 + }; + _iface->poke32(dsp_index_to_reg_val[dspno], freq_word); + + return (double(freq_word) / scale_factor) * _master_clock_rate; +} + +double usrp1_impl::update_tx_dsp_freq(const size_t dspno, const double freq){ + const subdev_spec_pair_t pair = _tx_subdev_spec.at(dspno); + + //determine the connection type and hence, the sign + const std::string conn = _tree->access<std::string>(str(boost::format( + "/mboards/0/dboards/%s/tx_frontends/%s/connection" + ) % pair.db_name % pair.sd_name)).get(); + double sign = (conn == "I" or conn == "IQ")? +1.0 : -1.0; + + //map this DSP's subdev spec to a particular codec chip + _dbc[pair.db_name].codec->set_duc_freq(sign*freq, _master_clock_rate); + return freq; //assume infinite precision +} + +/*********************************************************************** + * Async Data + **********************************************************************/ +bool usrp1_impl::recv_async_msg( + async_metadata_t &async_metadata, double timeout +){ + boost::this_thread::disable_interruption di; //disable because the wait can throw + return _soft_time_ctrl->get_async_queue().pop_with_timed_wait(async_metadata, timeout); +} + +/*********************************************************************** + * Receive streamer + **********************************************************************/ +rx_streamer::sptr usrp1_impl::get_rx_stream(const uhd::stream_args_t &args_){ + stream_args_t args = args_; + + //setup defaults for unspecified values + args.otw_format = args.otw_format.empty()? "sc16" : args.otw_format; + args.channels.clear(); //NOTE: we have no choice about the channel mapping + for (size_t ch = 0; ch < _rx_subdev_spec.size(); ch++){ + args.channels.push_back(ch); + } + + if (args.otw_format == "sc16"){ + _iface->poke32(FR_RX_FORMAT, 0 + | (0 << bmFR_RX_FORMAT_SHIFT_SHIFT) + | (16 << bmFR_RX_FORMAT_WIDTH_SHIFT) + | bmFR_RX_FORMAT_WANT_Q + ); + } + else if (args.otw_format == "sc8"){ + _iface->poke32(FR_RX_FORMAT, 0 + | (8 << bmFR_RX_FORMAT_SHIFT_SHIFT) + | (8 << bmFR_RX_FORMAT_WIDTH_SHIFT) + | bmFR_RX_FORMAT_WANT_Q + ); + } + else{ + throw uhd::value_error("USRP1 RX cannot handle requested wire format: " + args.otw_format); + } + + //calculate packet size + const size_t bpp = _data_transport->get_recv_frame_size()/args.channels.size(); + const size_t spp = bpp/convert::get_bytes_per_item(args.otw_format); + + //make the new streamer given the samples per packet + boost::shared_ptr<usrp1_recv_packet_streamer> my_streamer = + boost::make_shared<usrp1_recv_packet_streamer>(spp, _soft_time_ctrl); + + //init some streamer stuff + my_streamer->set_tick_rate(_master_clock_rate); + my_streamer->set_vrt_unpacker(&usrp1_bs_vrt_unpacker); + my_streamer->set_xport_chan_get_buff(0, boost::bind( + &uhd::transport::zero_copy_if::get_recv_buff, _io_impl->data_transport, _1 + )); + + //set the converter + uhd::convert::id_type id; + id.input_format = args.otw_format + "_item16_usrp1"; + id.num_inputs = 1; + id.output_format = args.cpu_format; + id.num_outputs = args.channels.size(); + my_streamer->set_converter(id); + + //special scale factor change for sc8 + if (args.otw_format == "sc8") + my_streamer->set_scale_factor(1.0/127); + + //save as weak ptr for update access + _rx_streamer = my_streamer; + + //sets all tick and samp rates on this streamer + this->update_rates(); + + return my_streamer; +} + +/*********************************************************************** + * Transmit streamer + **********************************************************************/ +tx_streamer::sptr usrp1_impl::get_tx_stream(const uhd::stream_args_t &args_){ + stream_args_t args = args_; + + //setup defaults for unspecified values + args.otw_format = args.otw_format.empty()? "sc16" : args.otw_format; + args.channels.clear(); //NOTE: we have no choice about the channel mapping + for (size_t ch = 0; ch < _tx_subdev_spec.size(); ch++){ + args.channels.push_back(ch); + } + + if (args.otw_format != "sc16"){ + throw uhd::value_error("USRP1 TX cannot handle requested wire format: " + args.otw_format); + } + + _iface->poke32(FR_TX_FORMAT, bmFR_TX_FORMAT_16_IQ); + + //calculate packet size + size_t bpp = _data_transport->get_send_frame_size()/args.channels.size(); + bpp -= alignment_padding - 1; //minus the max remainder after LUT commit + const size_t spp = bpp/convert::get_bytes_per_item(args.otw_format); + + //make the new streamer given the samples per packet + boost::function<void(bool)> tx_fcn = boost::bind(&usrp1_impl::tx_stream_on_off, this, _1); + boost::shared_ptr<usrp1_send_packet_streamer> my_streamer = + boost::make_shared<usrp1_send_packet_streamer>(spp, _soft_time_ctrl, tx_fcn); + + //init some streamer stuff + my_streamer->set_tick_rate(_master_clock_rate); + my_streamer->set_vrt_packer(&usrp1_bs_vrt_packer); + my_streamer->set_xport_chan_get_buff(0, boost::bind( + &usrp1_impl::io_impl::get_send_buff, _io_impl.get(), _1 + )); + + //set the converter + uhd::convert::id_type id; + id.input_format = args.cpu_format; + id.num_inputs = args.channels.size(); + id.output_format = args.otw_format + "_item16_usrp1"; + id.num_outputs = 1; + my_streamer->set_converter(id); + + //save as weak ptr for update access + _tx_streamer = my_streamer; + + //sets all tick and samp rates on this streamer + this->update_rates(); + + return my_streamer; +} |