aboutsummaryrefslogtreecommitdiffstats
path: root/host/lib/usrp
diff options
context:
space:
mode:
Diffstat (limited to 'host/lib/usrp')
-rw-r--r--host/lib/usrp/CMakeLists.txt1
-rw-r--r--host/lib/usrp/dsp_utils.hpp114
-rw-r--r--host/lib/usrp/usrp2/dsp_impl.cpp63
3 files changed, 122 insertions, 56 deletions
diff --git a/host/lib/usrp/CMakeLists.txt b/host/lib/usrp/CMakeLists.txt
index 39a72ab37..3e12c087e 100644
--- a/host/lib/usrp/CMakeLists.txt
+++ b/host/lib/usrp/CMakeLists.txt
@@ -22,6 +22,7 @@ LIBUHD_APPEND_SOURCES(
${CMAKE_SOURCE_DIR}/lib/usrp/dboard_eeprom.cpp
${CMAKE_SOURCE_DIR}/lib/usrp/dboard_id.cpp
${CMAKE_SOURCE_DIR}/lib/usrp/dboard_manager.cpp
+ ${CMAKE_SOURCE_DIR}/lib/usrp/dsp_utils.hpp
${CMAKE_SOURCE_DIR}/lib/usrp/simple_usrp.cpp
${CMAKE_SOURCE_DIR}/lib/usrp/tune_helper.cpp
)
diff --git a/host/lib/usrp/dsp_utils.hpp b/host/lib/usrp/dsp_utils.hpp
new file mode 100644
index 000000000..cfe5375f8
--- /dev/null
+++ b/host/lib/usrp/dsp_utils.hpp
@@ -0,0 +1,114 @@
+//
+// Copyright 2010 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/>.
+//
+
+#ifndef INCLUDED_LIBUHD_USRP_DSP_UTILS_HPP
+#define INCLUDED_LIBUHD_USRP_DSP_UTILS_HPP
+
+#include <uhd/config.hpp>
+#include <uhd/utils/assert.hpp>
+#include <boost/cstdint.hpp>
+#include <boost/math/special_functions/round.hpp>
+
+namespace uhd{ namespace usrp{
+
+namespace dsp_type1{
+
+ template <class T> T ceil_log2(T num){
+ return std::ceil(std::log(num)/std::log(T(2)));
+ }
+
+ /*!
+ * Calculate the cordic word from the frequency and clock rate.
+ * The frequency will be set to the actual (possible) frequency.
+ *
+ * \param freq the requested frequency in Hz
+ * \param codec_rate the dsp codec rate in Hz
+ * \param the 32-bit cordic control word
+ */
+ static inline boost::uint32_t calc_cordic_word_and_update(
+ double &freq,
+ double codec_rate
+ ){
+ UHD_ASSERT_THROW(std::abs(freq) < codec_rate/2.0);
+ static const double scale_factor = std::pow(2.0, 32);
+
+ //calculate the freq register word
+ boost::uint32_t freq_word = boost::math::iround((freq / codec_rate) * scale_factor);
+
+ //update the actual frequency
+ freq = (double(freq_word) / scale_factor) * codec_rate;
+
+ return freq_word;
+ }
+
+ /*!
+ * Calculate the CIC filter word from the rate.
+ * Check if requested decim/interp rate is:
+ * multiple of 4, enable two halfband filters
+ * multiple of 2, enable one halfband filter
+ * handle remainder in CIC
+ *
+ * \param rate the requested rate in Sps
+ * \return the 32-bit cic filter control word
+ */
+ template <typename dsp_rate_type>
+ static inline boost::uint32_t calc_cic_filter_word(dsp_rate_type rate){
+ int hb0 = 0, hb1 = 0;
+ if (not (rate & 0x1)){
+ hb0 = 1;
+ rate /= 2;
+ }
+ if (not (rate & 0x1)){
+ hb1 = 1;
+ rate /= 2;
+ }
+ return (hb1 << 9) | (hb0 << 8) | (rate & 0xff);
+ }
+
+ /*!
+ * Calculate the IQ scale factor word from I and Q components.
+ * \param i the I component of the scalar
+ * \param q the Q component of the scalar
+ * \return the 32-bit scale factor control word
+ */
+ static inline boost::uint32_t calc_iq_scale_word(
+ boost::int16_t i, boost::int16_t q
+ ){
+ return (boost::uint32_t(i) << 16) | (boost::uint32_t(q) << 0);
+ }
+
+ /*!
+ * Calculate the IQ scale factor word from the rate.
+ * \param rate the requested rate in Sps
+ * \return the 32-bit scale factor control word
+ */
+ template <typename dsp_rate_type>
+ static inline boost::uint32_t calc_iq_scale_word(dsp_rate_type rate){
+ // Calculate CIC interpolation (i.e., without halfband interpolators)
+ dsp_rate_type tmp_rate = calc_cic_filter_word(rate) & 0xff;
+
+ // Calculate closest multiplier constant to reverse gain absent scale multipliers
+ double rate_cubed = std::pow(double(tmp_rate), 3);
+ boost::int16_t scale = boost::math::iround((4096*std::pow(2, ceil_log2(rate_cubed)))/(1.65*rate_cubed));
+ return calc_iq_scale_word(scale, scale);
+ }
+
+} //namespace dsp_type1
+
+}} //namespace
+
+#endif /* INCLUDED_LIBUHD_USRP_DSP_UTILS_HPP */
diff --git a/host/lib/usrp/usrp2/dsp_impl.cpp b/host/lib/usrp/usrp2/dsp_impl.cpp
index 330638cb1..367cde2e1 100644
--- a/host/lib/usrp/usrp2/dsp_impl.cpp
+++ b/host/lib/usrp/usrp2/dsp_impl.cpp
@@ -17,12 +17,10 @@
#include "usrp2_impl.hpp"
#include "usrp2_regs.hpp"
+#include "../dsp_utils.hpp"
#include <uhd/usrp/dsp_props.hpp>
-#include <uhd/utils/assert.hpp>
-#include <boost/format.hpp>
#include <boost/bind.hpp>
#include <boost/assign/list_of.hpp>
-#include <boost/math/special_functions/round.hpp>
using namespace uhd;
using namespace uhd::usrp;
@@ -30,49 +28,9 @@ using namespace uhd::usrp;
static const size_t default_decim = 16;
static const size_t default_interp = 16;
-#define rint boost::math::iround
-
-template <class T> T log2(T num){
- return std::log(num)/std::log(T(2));
-}
-
/***********************************************************************
* DDC Helper Methods
**********************************************************************/
-static boost::uint32_t calculate_freq_word_and_update_actual_freq(double &freq, double clock_freq){
- UHD_ASSERT_THROW(std::abs(freq) < clock_freq/2.0);
- static const double scale_factor = std::pow(2.0, 32);
-
- //calculate the freq register word
- boost::uint32_t freq_word = rint((freq / clock_freq) * scale_factor);
-
- //update the actual frequency
- freq = (double(freq_word) / scale_factor) * clock_freq;
-
- return freq_word;
-}
-
-// Check if requested decim/interp rate is:
-// multiple of 4, enable two halfband filters
-// multiple of 2, enable one halfband filter
-// handle remainder in CIC
-static boost::uint32_t calculate_cic_word(size_t rate){
- int hb0 = 0, hb1 = 0;
- if (not (rate & 0x1)){
- hb0 = 1;
- rate /= 2;
- }
- if (not (rate & 0x1)){
- hb1 = 1;
- rate /= 2;
- }
- return (hb1 << 9) | (hb0 << 8) | (rate & 0xff);
-}
-
-static boost::uint32_t calculate_iq_scale_word(boost::int16_t i, boost::int16_t q){
- return (boost::uint16_t(i) << 16) | (boost::uint16_t(q) << 0);
-}
-
template <class rate_t> static rate_t
pick_closest_rate(double exact_rate, const std::vector<rate_t> &rates){
rate_t closest_match = rates.at(0);
@@ -130,7 +88,7 @@ void usrp2_impl::ddc_set(const wax::obj &key, const wax::obj &val){
case DSP_PROP_FREQ_SHIFT:{
double new_freq = val.as<double>();
_iface->poke32(U2_REG_DSP_RX_FREQ,
- calculate_freq_word_and_update_actual_freq(new_freq, get_master_clock_freq())
+ dsp_type1::calc_cordic_word_and_update(new_freq, get_master_clock_freq())
);
_ddc_freq = new_freq; //shadow
}
@@ -141,12 +99,12 @@ void usrp2_impl::ddc_set(const wax::obj &key, const wax::obj &val){
_ddc_decim = pick_closest_rate(extact_rate, _allowed_decim_and_interp_rates);
//set the decimation
- _iface->poke32(U2_REG_DSP_RX_DECIM_RATE, calculate_cic_word(_ddc_decim));
+ _iface->poke32(U2_REG_DSP_RX_DECIM_RATE, dsp_type1::calc_cic_filter_word(_ddc_decim));
//set the scaling
static const boost::int16_t default_rx_scale_iq = 1024;
_iface->poke32(U2_REG_DSP_RX_SCALE_IQ,
- calculate_iq_scale_word(default_rx_scale_iq, default_rx_scale_iq)
+ dsp_type1::calc_iq_scale_word(default_rx_scale_iq, default_rx_scale_iq)
);
}
return;
@@ -205,7 +163,7 @@ void usrp2_impl::duc_set(const wax::obj &key, const wax::obj &val){
case DSP_PROP_FREQ_SHIFT:{
double new_freq = val.as<double>();
_iface->poke32(U2_REG_DSP_TX_FREQ,
- calculate_freq_word_and_update_actual_freq(new_freq, get_master_clock_freq())
+ dsp_type1::calc_cordic_word_and_update(new_freq, get_master_clock_freq())
);
_duc_freq = new_freq; //shadow
}
@@ -215,18 +173,11 @@ void usrp2_impl::duc_set(const wax::obj &key, const wax::obj &val){
double extact_rate = get_master_clock_freq()/val.as<double>();
_duc_interp = pick_closest_rate(extact_rate, _allowed_decim_and_interp_rates);
- // Calculate CIC interpolation (i.e., without halfband interpolators)
- size_t tmp_interp = calculate_cic_word(_duc_interp) & 0xff;
-
- // Calculate closest multiplier constant to reverse gain absent scale multipliers
- double interp_cubed = std::pow(double(tmp_interp), 3);
- boost::int16_t scale = rint((4096*std::pow(2, ceil(log2(interp_cubed))))/(1.65*interp_cubed));
-
//set the interpolation
- _iface->poke32(U2_REG_DSP_TX_INTERP_RATE, calculate_cic_word(_duc_interp));
+ _iface->poke32(U2_REG_DSP_TX_INTERP_RATE, dsp_type1::calc_cic_filter_word(_duc_interp));
//set the scaling
- _iface->poke32(U2_REG_DSP_TX_SCALE_IQ, calculate_iq_scale_word(scale, scale));
+ _iface->poke32(U2_REG_DSP_TX_SCALE_IQ, dsp_type1::calc_iq_scale_word(_duc_interp));
}
return;