Merge pull request #45 from jketterl/biastee_support

Biastee support

Author: guruofquality

CMakeLists.txt

@@ -51,6 +51,15 @@ if (APPLE)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Wc++11-extensions")
 endif(APPLE)
 
+# check if rtlsdr library includes support for bias-tee
+include(CheckFunctionExists)
+set(CMAKE_REQUIRED_LIBRARIES ${RTLSDR_LIBRARIES})
+check_function_exists(rtlsdr_set_bias_tee HAS_RTLSDR_SET_BIAS_TEE)
+unset(CMAKE_REQUIRED_LIBRARIES)
+if (HAS_RTLSDR_SET_BIAS_TEE)
+    add_definitions(-DHAS_RTLSDR_SET_BIAS_TEE)
+endif()
+
 set(OTHER_LIBS "" CACHE STRING "Other libraries")
 
 SOAPY_SDR_MODULE_UTIL(

Settings.cpp

@@ -42,6 +42,9 @@ SoapyRTLSDR::SoapyRTLSDR(const SoapySDR::Kwargs &args):
     gainMode(false),
     offsetMode(false),
     digitalAGC(false),
+#if HAS_RTLSDR_SET_BIAS_TEE
+    biasTee(false),
+#endif
     ticks(false),
     bufferedElems(0),
     resetBuffer(false),
@@ -539,6 +542,18 @@ SoapySDR::ArgInfoList SoapyRTLSDR::getSettingInfo(void) const
 
     setArgs.push_back(digitalAGCArg);
 
+#if HAS_RTLSDR_SET_BIAS_TEE
+    SoapySDR::ArgInfo biasTeeArg;
+
+    biasTeeArg.key = "biastee";
+    biasTeeArg.value = "false";
+    biasTeeArg.name = "Bias Tee";
+    biasTeeArg.description = "RTL-SDR Blog V.3 Bias-Tee Mode";
+    biasTeeArg.type = SoapySDR::ArgInfo::BOOL;
+
+    setArgs.push_back(biasTeeArg);
+#endif
+
     SoapySDR_logf(SOAPY_SDR_DEBUG, "SETARGS?");
 
     return setArgs;
@@ -576,6 +591,14 @@ void SoapyRTLSDR::writeSetting(const std::string &key, const std::string &value)
         SoapySDR_logf(SOAPY_SDR_DEBUG, "RTL-SDR digital agc mode: %s", digitalAGC ? "true" : "false");
         rtlsdr_set_agc_mode(dev, digitalAGC ? 1 : 0);
     }
+#if HAS_RTLSDR_SET_BIAS_TEE
+    else if (key == "biastee")
+    {
+        biasTee = (value == "true") ? true: false;
+        SoapySDR_logf(SOAPY_SDR_DEBUG, "RTL-SDR bias tee mode: %s", biasTee ? "true" : "false");
+        rtlsdr_set_bias_tee(dev, biasTee ? 1 : 0);
+    }
+#endif
 }
 
 std::string SoapyRTLSDR::readSetting(const std::string &key) const
@@ -588,6 +611,10 @@ std::string SoapyRTLSDR::readSetting(const std::string &key) const
         return offsetMode?"true":"false";
     } else if (key == "digital_agc") {
         return digitalAGC?"true":"false";
+#if HAS_RTLSDR_SET_BIAS_TEE
+    } else if (key == "biastee") {
+        return biasTee?"true":"false";
+#endif
     }
 
     SoapySDR_logf(SOAPY_SDR_WARNING, "Unknown setting '%s'", key.c_str());

SoapyRTLSDR.hpp

@@ -243,7 +243,7 @@ class SoapyRTLSDR: public SoapySDR::Device
     uint32_t sampleRate, centerFrequency;
     int ppm, directSamplingMode;
     size_t numBuffers, bufferLength, asyncBuffs;
-    bool iqSwap, gainMode, offsetMode, digitalAGC;
+    bool iqSwap, gainMode, offsetMode, digitalAGC, biasTee;
     double IFGain[6], tunerGain;
     std::atomic<long long> ticks;