usrp: Added fe_connection type and unit test

- Wraps a sampling mode and IF frequency
- Built-in parser to deduce swap,invert,mode bits from string connection

2 files changed, 128 insertions, 0 deletions

diff --git a/host/include/uhd/usrp/CMakeLists.txt b/host/include/uhd/usrp/CMakeLists.txt
index 2d3717357..fd37ef560 100644
--- a/host/include/uhd/usrp/CMakeLists.txt
+++ b/host/include/uhd/usrp/CMakeLists.txt
@@ -18,6 +18,7 @@
 UHD_INSTALL(FILES
 
     #### dboard headers ###
+    fe_connection.hpp
     dboard_base.hpp
     dboard_eeprom.hpp
     dboard_id.hpp
diff --git a/host/include/uhd/usrp/fe_connection.hpp b/host/include/uhd/usrp/fe_connection.hpp
new file mode 100644
index 000000000..969246087
--- /dev/null
+++ b/host/include/uhd/usrp/fe_connection.hpp
@@ -0,0 +1,127 @@
+//
+// Copyright 2016 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_UHD_USRP_FE_CONNECTION_HPP
+#define INCLUDED_UHD_USRP_FE_CONNECTION_HPP
+
+#include <uhd/config.hpp>
+#include <boost/operators.hpp>
+#include <string>
+
+namespace uhd { namespace usrp {
+
+    class UHD_API fe_connection_t : boost::equality_comparable<fe_connection_t> {
+    public:
+        /** Sampling mode.
+         *  Represents the sampling architecture for the front-end
+         */
+        enum sampling_t {
+            QUADRATURE, /**< Complex sampling (Complex input, Complex output). */
+            HETERODYNE, /**< Heterodyne sampling (Real input, Complex output). Only one of the I and Q inputs is used. */
+            REAL        /**< Real sampling (Real input, Real output). Only one of the I and Q inputs is used. */
+        };
+
+        /*!
+         * Create a frontend connection class from individual settings.
+         * \param sampling_mode can be { QUADRATURE, HETERODYNE, REAL }
+         * \param iq_swapped indicates if the IQ channels are swapped (after inverion and heterodyne correction)
+         * \param i_inverted indicates if the I channel is inverted (negated)
+         * \param q_inverted indicates if the Q channel is inverted (negated)
+         * \param if_freq the baseband sampling frequency.
+         */
+        fe_connection_t(
+            sampling_t sampling_mode, bool iq_swapped,
+            bool i_inverted, bool q_inverted, double if_freq = 0.0
+        );
+
+        /*!
+         * Create a frontend connection class from a connection string
+         * The connection string can be:
+         * - in {I, Q}: Real mode sampling with no inversion.
+         * - in {Ib, Qb}: Real mode sampling with inversion.
+         * - in {IQ, QI}: Quadrature sampling with no inversion.
+         * - in {IbQb, QbIb}: Quadrature sampling with inversion.
+         * - in {II, QQ}: Heterodyne sampling with no inversion.
+         * - in {IbIb, QbQb}: Heterodyne sampling with inversion.
+         *
+         * \param conn_str the connection string.
+         * \param if_freq the baseband sampling frequency.
+         */
+        fe_connection_t(const std::string& conn_str, double if_freq = 0.0);
+
+        /*!
+         * Accessor for sampling mode
+         */
+        inline sampling_t get_sampling_mode() const {
+            return _sampling_mode;
+        }
+
+        /*!
+         * Accessor for IQ swap parameter
+         */
+        inline bool is_iq_swapped() const {
+            return _iq_swapped;
+        }
+
+        /*!
+         * Accessor for I inversion parameter
+         */
+        inline bool is_i_inverted() const {
+            return _i_inverted;
+        }
+
+        /*!
+         * Accessor for Q inversion parameter
+         */
+        inline bool is_q_inverted() const {
+            return _q_inverted;
+        }
+
+        /*!
+         * Accessor for IF frequency
+         */
+        inline double get_if_freq() const {
+            return _if_freq;
+        }
+
+        /*!
+         * Mutator for IF frequency
+         */
+        inline void set_if_freq(double freq) {
+            _if_freq = freq;
+        }
+
+    private:
+        sampling_t  _sampling_mode;
+        bool        _iq_swapped;
+        bool        _i_inverted;
+        bool        _q_inverted;
+        double      _if_freq;
+    };
+
+    /*!
+     * Comparator operator overloaded for fe_connection_t.
+     * The boost::equality_comparable provides the !=.
+     * \param lhs the fe_connection_t to the left of the operator
+     * \param rhs the fe_connection_t to the right of the operator
+     * \return true when the fe connections are equal
+     */
+    UHD_API bool operator==(const fe_connection_t &lhs, const fe_connection_t &rhs);
+
+}} //namespace
+
+#endif /* INCLUDED_UHD_USRP_FE_CONNECTION_HPP */