Get fixed_point working with USRP

1 files changed, 16 insertions, 10 deletions

diff --git a/src/DabMod.cpp b/src/DabMod.cpp
index 5f8412b..739fef1 100644
--- a/src/DabMod.cpp
+++ b/src/DabMod.cpp
@@ -72,10 +72,12 @@
  * samples can have peaks up to about 48000. The value of 50000
  * should guarantee that with a digital gain of 1.0, UHD never clips
  * our samples.
+ *
+ * This only applies when fixed_point == false.
  */
 static const float normalise_factor = 50000.0f;
 
-//Empirical normalisation factors used to normalise the samples to amplitude 1.
+// Empirical normalisation factors used to normalise the samples to amplitude 1.
 static const float normalise_factor_file_fix = 81000.0f;
 static const float normalise_factor_file_var = 46000.0f;
 static const float normalise_factor_file_max = 46000.0f;
@@ -249,16 +251,12 @@ static shared_ptr<ModOutput> prepare_output(mod_settings_t& s)
 {
     shared_ptr<ModOutput> output;
 
-    if (s.fixedPoint) {
-        if (s.useFileOutput) {
+    if (s.useFileOutput) {
+        if (s.fixedPoint) {
+            // Intentionally ignore fileOutputFormat, it is always sc16
             output = make_shared<OutputFile>(s.outputName, s.fileOutputShowMetadata);
         }
-        else {
-            throw runtime_error("Fixed point only works with file output");
-        }
-    }
-    else if (s.useFileOutput) {
-        if (s.fileOutputFormat == "complexf") {
+        else if (s.fileOutputFormat == "complexf") {
             output = make_shared<OutputFile>(s.outputName, s.fileOutputShowMetadata);
         }
         else if (s.fileOutputFormat == "complexf_normalised") {
@@ -294,6 +292,7 @@ static shared_ptr<ModOutput> prepare_output(mod_settings_t& s)
     else if (s.useUHDOutput) {
         s.normalise = 1.0f / normalise_factor;
         s.sdr_device_config.sampleRate = s.outputRate;
+        s.sdr_device_config.fixedPoint = s.fixedPoint;
         auto uhddevice = make_shared<Output::UHD>(s.sdr_device_config);
         output = make_shared<Output::SDR>(s.sdr_device_config, uhddevice);
         rcs.enrol((Output::SDR*)output.get());
@@ -304,6 +303,7 @@ static shared_ptr<ModOutput> prepare_output(mod_settings_t& s)
         /* We normalise the same way as for the UHD output */
         s.normalise = 1.0f / normalise_factor;
         s.sdr_device_config.sampleRate = s.outputRate;
+        if (s.fixedPoint) throw runtime_error("soapy fixed_point unsupported");
         auto soapydevice = make_shared<Output::Soapy>(s.sdr_device_config);
         output = make_shared<Output::SDR>(s.sdr_device_config, soapydevice);
         rcs.enrol((Output::SDR*)output.get());
@@ -313,6 +313,7 @@ static shared_ptr<ModOutput> prepare_output(mod_settings_t& s)
     else if (s.useDexterOutput) {
         /* We normalise specifically range [-32768; 32767] */
         s.normalise = 32767.0f / normalise_factor;
+        if (s.fixedPoint) throw runtime_error("dexter fixed_point unsupported");
         s.sdr_device_config.sampleRate = s.outputRate;
         auto dexterdevice = make_shared<Output::Dexter>(s.sdr_device_config);
         output = make_shared<Output::SDR>(s.sdr_device_config, dexterdevice);
@@ -323,6 +324,7 @@ static shared_ptr<ModOutput> prepare_output(mod_settings_t& s)
     else if (s.useLimeOutput) {
         /* We normalise the same way as for the UHD output */
         s.normalise = 1.0f / normalise_factor;
+        if (s.fixedPoint) throw runtime_error("limesdr fixed_point unsupported");
         s.sdr_device_config.sampleRate = s.outputRate;
         auto limedevice = make_shared<Output::Lime>(s.sdr_device_config);
         output = make_shared<Output::SDR>(s.sdr_device_config, limedevice);
@@ -333,6 +335,7 @@ static shared_ptr<ModOutput> prepare_output(mod_settings_t& s)
     else if (s.useBladeRFOutput) {
         /* We normalise specifically for the BladeRF output : range [-2048; 2047] */
         s.normalise = 2047.0f / normalise_factor;
+        if (s.fixedPoint) throw runtime_error("bladerf fixed_point unsupported");
         s.sdr_device_config.sampleRate = s.outputRate;
         auto bladerfdevice = make_shared<Output::BladeRF>(s.sdr_device_config);
         output = make_shared<Output::SDR>(s.sdr_device_config, bladerfdevice);
@@ -443,7 +446,10 @@ int launch_modulator(int argc, char* argv[])
     }
 
     std::string output_format;
-    if (mod_settings.useFileOutput and
+    if (mod_settings.fixedPoint) {
+        output_format = "fixedpoint";
+    }
+    else if (mod_settings.useFileOutput and
             (mod_settings.fileOutputFormat == "s8" or
              mod_settings.fileOutputFormat == "u8" or
              mod_settings.fileOutputFormat == "s16")) {