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diff --git a/host/lib/usrp/dboard/db_dbsrx.cpp b/host/lib/usrp/dboard/db_dbsrx.cpp
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+++ b/host/lib/usrp/dboard/db_dbsrx.cpp
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+//
+// 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/>.
+//
+
+// No RX IO Pins Used
+
+// RX IO Functions
+
+#include "max2118_regs.hpp"
+#include <uhd/utils/log.hpp>
+#include <uhd/utils/static.hpp>
+#include <uhd/utils/assert_has.hpp>
+#include <uhd/utils/algorithm.hpp>
+#include <uhd/utils/msg.hpp>
+#include <uhd/types/ranges.hpp>
+#include <uhd/types/sensors.hpp>
+#include <uhd/types/dict.hpp>
+#include <uhd/usrp/dboard_base.hpp>
+#include <uhd/usrp/dboard_manager.hpp>
+#include <boost/assign/list_of.hpp>
+#include <boost/format.hpp>
+#include <boost/thread.hpp>
+#include <boost/math/special_functions/round.hpp>
+#include <utility>
+#include <cmath>
+
+using namespace uhd;
+using namespace uhd::usrp;
+using namespace boost::assign;
+
+/***********************************************************************
+ * The DBSRX constants
+ **********************************************************************/
+static const freq_range_t dbsrx_freq_range(0.8e9, 2.4e9);
+
+//Multiplied by 2.0 for conversion to complex bandpass from lowpass
+static const freq_range_t dbsrx_bandwidth_range(2.0*4.0e6, 2.0*33.0e6);
+
+static const freq_range_t dbsrx_pfd_freq_range(0.15e6, 2.01e6);
+
+static const std::vector<std::string> dbsrx_antennas = list_of("J3");
+
+static const uhd::dict<std::string, gain_range_t> dbsrx_gain_ranges = map_list_of
+ ("GC1", gain_range_t(0, 56, 0.5))
+ ("GC2", gain_range_t(0, 24, 1))
+;
+
+static const double usrp1_gpio_clock_rate_limit = 4e6;
+
+/***********************************************************************
+ * The DBSRX dboard class
+ **********************************************************************/
+class dbsrx : public rx_dboard_base{
+public:
+ dbsrx(ctor_args_t args);
+ ~dbsrx(void);
+
+private:
+ double _lo_freq;
+ double _bandwidth;
+ uhd::dict<std::string, double> _gains;
+ max2118_write_regs_t _max2118_write_regs;
+ max2118_read_regs_t _max2118_read_regs;
+ boost::uint8_t _max2118_addr(void){
+ return (this->get_iface()->get_special_props().mangle_i2c_addrs)? 0x65 : 0x67;
+ };
+
+ double set_lo_freq(double target_freq);
+ double set_gain(double gain, const std::string &name);
+ double set_bandwidth(double bandwidth);
+
+ void send_reg(boost::uint8_t start_reg, boost::uint8_t stop_reg){
+ start_reg = boost::uint8_t(uhd::clip(int(start_reg), 0x0, 0x5));
+ stop_reg = boost::uint8_t(uhd::clip(int(stop_reg), 0x0, 0x5));
+
+ for(boost::uint8_t start_addr=start_reg; start_addr <= stop_reg; start_addr += sizeof(boost::uint32_t) - 1){
+ int num_bytes = int(stop_reg - start_addr + 1) > int(sizeof(boost::uint32_t)) - 1 ? sizeof(boost::uint32_t) - 1 : stop_reg - start_addr + 1;
+
+ //create buffer for register data (+1 for start address)
+ byte_vector_t regs_vector(num_bytes + 1);
+
+ //first byte is the address of first register
+ regs_vector[0] = start_addr;
+
+ //get the register data
+ for(int i=0; i<num_bytes; i++){
+ regs_vector[1+i] = _max2118_write_regs.get_reg(start_addr+i);
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: send reg 0x%02x, value 0x%04x, start_addr = 0x%04x, num_bytes %d"
+ ) % int(start_addr+i) % int(regs_vector[1+i]) % int(start_addr) % num_bytes << std::endl;
+ }
+
+ //send the data
+ this->get_iface()->write_i2c(
+ _max2118_addr(), regs_vector
+ );
+ }
+ }
+
+ void read_reg(boost::uint8_t start_reg, boost::uint8_t stop_reg){
+ static const boost::uint8_t status_addr = 0x0;
+ start_reg = boost::uint8_t(uhd::clip(int(start_reg), 0x0, 0x1));
+ stop_reg = boost::uint8_t(uhd::clip(int(stop_reg), 0x0, 0x1));
+
+ for(boost::uint8_t start_addr=start_reg; start_addr <= stop_reg; start_addr += sizeof(boost::uint32_t)){
+ int num_bytes = int(stop_reg - start_addr + 1) > int(sizeof(boost::uint32_t)) ? sizeof(boost::uint32_t) : stop_reg - start_addr + 1;
+
+ //create buffer for register data
+ byte_vector_t regs_vector(num_bytes);
+
+ //read from i2c
+ regs_vector = this->get_iface()->read_i2c(
+ _max2118_addr(), num_bytes
+ );
+
+ for(boost::uint8_t i=0; i < num_bytes; i++){
+ if (i + start_addr >= status_addr){
+ _max2118_read_regs.set_reg(i + start_addr, regs_vector[i]);
+ }
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: read reg 0x%02x, value 0x%04x, start_addr = 0x%04x, num_bytes %d"
+ ) % int(start_addr+i) % int(regs_vector[i]) % int(start_addr) % num_bytes << std::endl;
+ }
+ }
+ }
+
+ /*!
+ * Get the lock detect status of the LO.
+ * \return sensor for locked
+ */
+ sensor_value_t get_locked(void){
+ read_reg(0x0, 0x0);
+
+ //mask and return lock detect
+ bool locked = 5 >= _max2118_read_regs.adc and _max2118_read_regs.adc >= 2;
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: locked %d"
+ ) % locked << std::endl;
+
+ return sensor_value_t("LO", locked, "locked", "unlocked");
+ }
+};
+
+/***********************************************************************
+ * Register the DBSRX dboard
+ **********************************************************************/
+static dboard_base::sptr make_dbsrx(dboard_base::ctor_args_t args){
+ return dboard_base::sptr(new dbsrx(args));
+}
+
+UHD_STATIC_BLOCK(reg_dbsrx_dboard){
+ //register the factory function for the rx dbid (others version)
+ dboard_manager::register_dboard(0x000D, &make_dbsrx, "DBSRX");
+ //register the factory function for the rx dbid (USRP1 version)
+ dboard_manager::register_dboard(0x0002, &make_dbsrx, "DBSRX");
+}
+
+/***********************************************************************
+ * Structors
+ **********************************************************************/
+dbsrx::dbsrx(ctor_args_t args) : rx_dboard_base(args){
+ //warn user about incorrect DBID on USRP1, requires R193 populated
+ if (this->get_iface()->get_special_props().soft_clock_divider and this->get_rx_id() == 0x000D)
+ UHD_MSG(warning) << boost::format(
+ "DBSRX: incorrect dbid\n"
+ "Expected dbid 0x0002 and R193\n"
+ "found dbid == %d\n"
+ "Please see the daughterboard app notes"
+ ) % this->get_rx_id().to_pp_string();
+
+ //warn user about incorrect DBID on non-USRP1, requires R194 populated
+ if (not this->get_iface()->get_special_props().soft_clock_divider and this->get_rx_id() == 0x0002)
+ UHD_MSG(warning) << boost::format(
+ "DBSRX: incorrect dbid\n"
+ "Expected dbid 0x000D and R194\n"
+ "found dbid == %d\n"
+ "Please see the daughterboard app notes"
+ ) % this->get_rx_id().to_pp_string();
+
+ //send initial register settings
+ this->send_reg(0x0, 0x5);
+
+ //set defaults for LO, gains, and filter bandwidth
+ double codec_rate = this->get_iface()->get_codec_rate(dboard_iface::UNIT_RX);
+ _bandwidth = 0.8*codec_rate/2.0; // default to anti-alias at different codec_rate
+
+ ////////////////////////////////////////////////////////////////////
+ // Register properties
+ ////////////////////////////////////////////////////////////////////
+ this->get_rx_subtree()->create<std::string>("name")
+ .set("DBSRX");
+ this->get_rx_subtree()->create<sensor_value_t>("sensors/lo_locked")
+ .publish(boost::bind(&dbsrx::get_locked, this));
+ BOOST_FOREACH(const std::string &name, dbsrx_gain_ranges.keys()){
+ this->get_rx_subtree()->create<double>("gains/"+name+"/value")
+ .coerce(boost::bind(&dbsrx::set_gain, this, _1, name))
+ .set(dbsrx_gain_ranges[name].start());
+ this->get_rx_subtree()->create<meta_range_t>("gains/"+name+"/range")
+ .set(dbsrx_gain_ranges[name]);
+ }
+ this->get_rx_subtree()->create<double>("freq/value")
+ .coerce(boost::bind(&dbsrx::set_lo_freq, this, _1));
+ this->get_rx_subtree()->create<meta_range_t>("freq/range")
+ .set(dbsrx_freq_range);
+ this->get_rx_subtree()->create<std::string>("antenna/value")
+ .set(dbsrx_antennas.at(0));
+ this->get_rx_subtree()->create<std::vector<std::string> >("antenna/options")
+ .set(dbsrx_antennas);
+ this->get_rx_subtree()->create<std::string>("connection")
+ .set("IQ");
+ this->get_rx_subtree()->create<bool>("enabled")
+ .set(true); //always enabled
+ this->get_rx_subtree()->create<bool>("use_lo_offset")
+ .set(false);
+ this->get_rx_subtree()->create<double>("bandwidth/value")
+ .coerce(boost::bind(&dbsrx::set_bandwidth, this, _1));
+ this->get_rx_subtree()->create<meta_range_t>("bandwidth/range")
+ .set(dbsrx_bandwidth_range);
+
+ //enable only the clocks we need
+ this->get_iface()->set_clock_enabled(dboard_iface::UNIT_RX, true);
+
+ //set the gpio directions and atr controls (identically)
+ this->get_iface()->set_pin_ctrl(dboard_iface::UNIT_RX, 0x0); // All unused in atr
+ if (this->get_iface()->get_special_props().soft_clock_divider){
+ this->get_iface()->set_gpio_ddr(dboard_iface::UNIT_RX, 0x1); // GPIO0 is clock when on USRP1
+ }
+ else{
+ this->get_iface()->set_gpio_ddr(dboard_iface::UNIT_RX, 0x0); // All Inputs
+ }
+
+ //now its safe to set inital freq and bw
+ this->get_rx_subtree()->access<double>("freq/value")
+ .set(dbsrx_freq_range.start());
+ this->get_rx_subtree()->access<double>("bandwidth/value")
+ .set(2.0*_bandwidth); //_bandwidth in lowpass, convert to complex bandpass
+}
+
+dbsrx::~dbsrx(void){
+}
+
+
+/***********************************************************************
+ * Tuning
+ **********************************************************************/
+double dbsrx::set_lo_freq(double target_freq){
+ target_freq = dbsrx_freq_range.clip(target_freq);
+
+ double actual_freq=0.0, pfd_freq=0.0, ref_clock=0.0;
+ int R=0, N=0, r=0, m=0;
+ bool update_filter_settings = false;
+ //choose refclock
+ std::vector<double> clock_rates = this->get_iface()->get_clock_rates(dboard_iface::UNIT_RX);
+ const double max_clock_rate = uhd::sorted(clock_rates).back();
+ BOOST_FOREACH(ref_clock, uhd::reversed(uhd::sorted(clock_rates))){
+ //USRP1 feeds the DBSRX clock from a FPGA GPIO line.
+ //make sure that this clock does not exceed rate limit.
+ if (this->get_iface()->get_special_props().soft_clock_divider){
+ if (ref_clock > usrp1_gpio_clock_rate_limit) continue;
+ }
+ if (ref_clock > 27.0e6) continue;
+ if (size_t(max_clock_rate/ref_clock)%2 == 1) continue; //reject asymmetric clocks (odd divisors)
+
+ //choose m_divider such that filter tuning constraint is met
+ m = 31;
+ while ((ref_clock/m < 1e6 or ref_clock/m > 2.5e6) and m > 0){ m--; }
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: trying ref_clock %f and m_divider %d"
+ ) % (ref_clock) % m << std::endl;
+
+ if (m >= 32) continue;
+
+ //choose R
+ for(r = 0; r <= 6; r += 1) {
+ //compute divider from setting
+ R = 1 << (r+1);
+ UHD_LOGV(often) << boost::format("DBSRX R:%d\n") % R << std::endl;
+
+ //compute PFD compare frequency = ref_clock/R
+ pfd_freq = ref_clock / R;
+
+ //constrain the PFD frequency to specified range
+ if ((pfd_freq < dbsrx_pfd_freq_range.start()) or (pfd_freq > dbsrx_pfd_freq_range.stop())) continue;
+
+ //compute N
+ N = int(std::floor(target_freq/pfd_freq));
+
+ //constrain N to specified range
+ if ((N < 256) or (N > 32768)) continue;
+
+ goto done_loop;
+ }
+ }
+
+ done_loop:
+
+ //Assert because we failed to find a suitable combination of ref_clock, R and N
+ UHD_ASSERT_THROW(ref_clock <= 27.0e6 and ref_clock >= 0.0);
+ UHD_ASSERT_THROW(ref_clock/m >= 1e6 and ref_clock/m <= 2.5e6);
+ UHD_ASSERT_THROW((pfd_freq >= dbsrx_pfd_freq_range.start()) and (pfd_freq <= dbsrx_pfd_freq_range.stop()));
+ UHD_ASSERT_THROW((N >= 256) and (N <= 32768));
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: choose ref_clock (current: %f, new: %f) and m_divider %d"
+ ) % (this->get_iface()->get_clock_rate(dboard_iface::UNIT_RX)) % ref_clock % m << std::endl;
+
+ //if ref_clock or m divider changed, we need to update the filter settings
+ if (ref_clock != this->get_iface()->get_clock_rate(dboard_iface::UNIT_RX) or m != _max2118_write_regs.m_divider) update_filter_settings = true;
+
+ //compute resulting output frequency
+ actual_freq = pfd_freq * N;
+
+ //apply ref_clock, R, and N settings
+ this->get_iface()->set_clock_rate(dboard_iface::UNIT_RX, ref_clock);
+ ref_clock = this->get_iface()->get_clock_rate(dboard_iface::UNIT_RX);
+ _max2118_write_regs.m_divider = m;
+ _max2118_write_regs.r_divider = (max2118_write_regs_t::r_divider_t) r;
+ _max2118_write_regs.set_n_divider(N);
+ _max2118_write_regs.ade_vco_ade_read = max2118_write_regs_t::ADE_VCO_ADE_READ_ENABLED;
+
+ //compute prescaler variables
+ int scaler = actual_freq > 1125e6 ? 2 : 4;
+ _max2118_write_regs.div2 = scaler == 4 ? max2118_write_regs_t::DIV2_DIV4 : max2118_write_regs_t::DIV2_DIV2;
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: scaler %d, actual_freq %f MHz, register bit: %d"
+ ) % scaler % (actual_freq/1e6) % int(_max2118_write_regs.div2) << std::endl;
+
+ //compute vco frequency and select vco
+ double vco_freq = actual_freq * scaler;
+ if (vco_freq < 2433e6)
+ _max2118_write_regs.osc_band = 0;
+ else if (vco_freq < 2711e6)
+ _max2118_write_regs.osc_band = 1;
+ else if (vco_freq < 3025e6)
+ _max2118_write_regs.osc_band = 2;
+ else if (vco_freq < 3341e6)
+ _max2118_write_regs.osc_band = 3;
+ else if (vco_freq < 3727e6)
+ _max2118_write_regs.osc_band = 4;
+ else if (vco_freq < 4143e6)
+ _max2118_write_regs.osc_band = 5;
+ else if (vco_freq < 4493e6)
+ _max2118_write_regs.osc_band = 6;
+ else
+ _max2118_write_regs.osc_band = 7;
+
+ //send settings over i2c
+ send_reg(0x0, 0x4);
+
+ //check vtune for lock condition
+ read_reg(0x0, 0x0);
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: initial guess for vco %d, vtune adc %d"
+ ) % int(_max2118_write_regs.osc_band) % int(_max2118_read_regs.adc) << std::endl;
+
+ //if we are out of lock for chosen vco, change vco
+ while ((_max2118_read_regs.adc == 0) or (_max2118_read_regs.adc == 7)){
+
+ //vtune is too low, try lower frequency vco
+ if (_max2118_read_regs.adc == 0){
+ if (_max2118_write_regs.osc_band == 0){
+ UHD_MSG(warning) << boost::format(
+ "DBSRX: Tuning exceeded vco range, _max2118_write_regs.osc_band == %d\n"
+ ) % int(_max2118_write_regs.osc_band);
+ UHD_ASSERT_THROW(_max2118_read_regs.adc != 0); //just to cause a throw
+ }
+ if (_max2118_write_regs.osc_band <= 0) break;
+ _max2118_write_regs.osc_band -= 1;
+ }
+
+ //vtune is too high, try higher frequency vco
+ if (_max2118_read_regs.adc == 7){
+ if (_max2118_write_regs.osc_band == 7){
+ UHD_MSG(warning) << boost::format(
+ "DBSRX: Tuning exceeded vco range, _max2118_write_regs.osc_band == %d\n"
+ ) % int(_max2118_write_regs.osc_band);
+ UHD_ASSERT_THROW(_max2118_read_regs.adc != 7); //just to cause a throw
+ }
+ if (_max2118_write_regs.osc_band >= 7) break;
+ _max2118_write_regs.osc_band += 1;
+ }
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: trying vco %d, vtune adc %d"
+ ) % int(_max2118_write_regs.osc_band) % int(_max2118_read_regs.adc) << std::endl;
+
+ //update vco selection and check vtune
+ send_reg(0x2, 0x2);
+ read_reg(0x0, 0x0);
+
+ //allow for setup time before checking condition again
+ boost::this_thread::sleep(boost::posix_time::milliseconds(10));
+ }
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX: final vco %d, vtune adc %d"
+ ) % int(_max2118_write_regs.osc_band) % int(_max2118_read_regs.adc) << std::endl;
+
+ //select charge pump bias current
+ if (_max2118_read_regs.adc <= 2) _max2118_write_regs.cp_current = max2118_write_regs_t::CP_CURRENT_I_CP_100UA;
+ else if (_max2118_read_regs.adc >= 5) _max2118_write_regs.cp_current = max2118_write_regs_t::CP_CURRENT_I_CP_400UA;
+ else _max2118_write_regs.cp_current = max2118_write_regs_t::CP_CURRENT_I_CP_200UA;
+
+ //update charge pump bias current setting
+ send_reg(0x2, 0x2);
+
+ //compute actual tuned frequency
+ _lo_freq = this->get_iface()->get_clock_rate(dboard_iface::UNIT_RX) / std::pow(2.0,(1 + _max2118_write_regs.r_divider)) * _max2118_write_regs.get_n_divider();
+
+ //debug output of calculated variables
+ UHD_LOGV(often)
+ << boost::format("DBSRX tune:\n")
+ << boost::format(" VCO=%d, CP=%d, PFD Freq=%fMHz\n") % int(_max2118_write_regs.osc_band) % _max2118_write_regs.cp_current % (pfd_freq/1e6)
+ << boost::format(" R=%d, N=%f, scaler=%d, div2=%d\n") % R % N % scaler % int(_max2118_write_regs.div2)
+ << boost::format(" Ref Freq=%fMHz\n") % (ref_clock/1e6)
+ << boost::format(" Target Freq=%fMHz\n") % (target_freq/1e6)
+ << boost::format(" Actual Freq=%fMHz\n") % (_lo_freq/1e6)
+ << boost::format(" VCO Freq=%fMHz\n") % (vco_freq/1e6)
+ << std::endl;
+
+ if (update_filter_settings) set_bandwidth(_bandwidth);
+ get_locked();
+
+ return _lo_freq;
+}
+
+/***********************************************************************
+ * Gain Handling
+ **********************************************************************/
+/*!
+ * Convert a requested gain for the GC2 vga into the integer register value.
+ * The gain passed into the function will be set to the actual value.
+ * \param gain the requested gain in dB
+ * \return 5 bit the register value
+ */
+static int gain_to_gc2_vga_reg(double &gain){
+ int reg = 0;
+ gain = dbsrx_gain_ranges["GC2"].clip(gain);
+
+ // Half dB steps from 0-5dB, 1dB steps from 5-24dB
+ if (gain < 5) {
+ reg = boost::math::iround(31.0 - gain/0.5);
+ gain = double(boost::math::iround(gain) * 0.5);
+ } else {
+ reg = boost::math::iround(22.0 - (gain - 4.0));
+ gain = double(boost::math::iround(gain));
+ }
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX GC2 Gain: %f dB, reg: %d"
+ ) % gain % reg << std::endl;
+
+ return reg;
+}
+
+/*!
+ * Convert a requested gain for the GC1 rf vga into the dac_volts value.
+ * The gain passed into the function will be set to the actual value.
+ * \param gain the requested gain in dB
+ * \return dac voltage value
+ */
+static double gain_to_gc1_rfvga_dac(double &gain){
+ //clip the input
+ gain = dbsrx_gain_ranges["GC1"].clip(gain);
+
+ //voltage level constants
+ static const double max_volts = 1.2, min_volts = 2.7;
+ static const double slope = (max_volts-min_volts)/dbsrx_gain_ranges["GC1"].stop();
+
+ //calculate the voltage for the aux dac
+ double dac_volts = gain*slope + min_volts;
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX GC1 Gain: %f dB, dac_volts: %f V"
+ ) % gain % dac_volts << std::endl;
+
+ //the actual gain setting
+ gain = (dac_volts - min_volts)/slope;
+
+ return dac_volts;
+}
+
+double dbsrx::set_gain(double gain, const std::string &name){
+ assert_has(dbsrx_gain_ranges.keys(), name, "dbsrx gain name");
+ if (name == "GC2"){
+ _max2118_write_regs.gc2 = gain_to_gc2_vga_reg(gain);
+ send_reg(0x5, 0x5);
+ }
+ else if(name == "GC1"){
+ //write the new voltage to the aux dac
+ this->get_iface()->write_aux_dac(dboard_iface::UNIT_RX, dboard_iface::AUX_DAC_A, gain_to_gc1_rfvga_dac(gain));
+ }
+ else UHD_THROW_INVALID_CODE_PATH();
+ _gains[name] = gain;
+
+ return gain;
+}
+
+/***********************************************************************
+ * Bandwidth Handling
+ **********************************************************************/
+double dbsrx::set_bandwidth(double bandwidth){
+ //convert complex bandpass to lowpass bandwidth
+ bandwidth = bandwidth/2.0;
+
+ //clip the input
+ bandwidth = dbsrx_bandwidth_range.clip(bandwidth);
+
+ double ref_clock = this->get_iface()->get_clock_rate(dboard_iface::UNIT_RX);
+
+ //NOTE: _max2118_write_regs.m_divider set in set_lo_freq
+
+ //compute f_dac setting
+ _max2118_write_regs.f_dac = uhd::clip<int>(int((((bandwidth*_max2118_write_regs.m_divider)/ref_clock) - 4)/0.145),0,127);
+
+ //determine actual bandwidth
+ _bandwidth = double((ref_clock/(_max2118_write_regs.m_divider))*(4+0.145*_max2118_write_regs.f_dac));
+
+ UHD_LOGV(often) << boost::format(
+ "DBSRX Filter Bandwidth: %f MHz, m: %d, f_dac: %d\n"
+ ) % (_bandwidth/1e6) % int(_max2118_write_regs.m_divider) % int(_max2118_write_regs.f_dac) << std::endl;
+
+ this->send_reg(0x3, 0x4);
+
+ //convert lowpass back to complex bandpass bandwidth
+ return 2.0*_bandwidth;
+}