Index: MessagePayloads.h
===================================================================
diff -u -r9e1f1a6979c06dafaaf5f95912de5bc25a10f86c -r718df5454eca61e57d0a35420cc9a1760336fa12
--- MessagePayloads.h	(.../MessagePayloads.h)	(revision 9e1f1a6979c06dafaaf5f95912de5bc25a10f86c)
+++ MessagePayloads.h	(.../MessagePayloads.h)	(revision 718df5454eca61e57d0a35420cc9a1760336fa12)
@@ -99,6 +99,13 @@
     F32 currentQd;                         ///< Current dialysate flow rate (ml/min)
 } GEN_DIALYSATE_MODE_DATA_T;
 
+/// Chamber H vent open request data
+typedef struct
+{
+    BOOL chamberHValveOpen;
+    BOOL primeFluidDiscardStart;
+} PRIME_DATA_REQ_PAYLOAD_T;
+
 #pragma pack(pop)
 
 /// Enumeration of operation modes.  These are in order of priority (highest to lowest).