uhd: Add command line option for GPS reference

Unlike earlier versions of UHD, the current release (3.9.2)
does not automatically select on-board GPSDO as the reference
source. Modify the command line settings to allow explicit
selection of GPS in addition to the external setting.

Simultaneous GPS and external reference settingis disallowed.

Signed-off-by: Tom Tsou <tom.tsou@ettus.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/Transceiver52M/radioDevice.h b/Transceiver52M/radioDevice.h
index 142fcf6..711d678 100644
--- a/Transceiver52M/radioDevice.h
+++ b/Transceiver52M/radioDevice.h
@@ -44,11 +44,17 @@ class RadioDevice {
     DIVERSITY,
   };
 
+  enum ReferenceType {
+    REF_INTERNAL,
+    REF_EXTERNAL,
+    REF_GPS,
+  };
+
   static RadioDevice *make(size_t tx_sps, size_t rx_sps, InterfaceType type,
                            size_t chans = 1, double offset = 0.0);
 
   /** Initialize the USRP */
-  virtual int open(const std::string &args = "", bool extref = false, bool swap_channels = false)=0;
+  virtual int open(const std::string &args, int ref, bool swap_channels)=0;
 
   virtual ~RadioDevice() { }