Index: firmware/App/Controllers/DGInterface.h
===================================================================
diff -u -raeb1dea9ea10fcc70ae66023a87b565f29924c07 -rd4a90fda6c1f463633a4e7d45424acd2d2a0bce8
--- firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision aeb1dea9ea10fcc70ae66023a87b565f29924c07)
+++ firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision d4a90fda6c1f463633a4e7d45424acd2d2a0bce8)
@@ -116,6 +116,13 @@
     F32 HtrTrimInternal;
 } DG_TEMPERATURES_T;
 
+/// Payload record structure for a drain reservoir command message.
+typedef struct
+{
+    U32  drainToVolumeML;
+    BOOL tareLoadCells;
+} DRAIN_RESERVOIR_CMD_PAYLOAD_T;
+
 // ********** public function prototypes **********
 
 void initDGInterface( void );
@@ -151,7 +158,7 @@
 void cmdStopDG( void );
 void cmdSetDGActiveReservoir( DG_RESERVOIR_ID_T resID );
 void cmdStartDGFill( U32 fillToVolMl );
-void cmdStartDGDrain( U32 drainToVolMl );
+void cmdStartDGDrain( U32 drainToVolMl, BOOL tareLoadCell );
 void cmdStartDGTrimmerHeater( void );
 void cmdStopDGTrimmerHeater( void );
 void cmdDGSampleWater( void );