Index: MsgDefs.h
===================================================================
diff -u -ra28aee98cd045d638c1fb5d8ecfee61280ce55dc -rabb6a2d2ac9f42a4d195b375c9843dc45c846865
--- MsgDefs.h	(.../MsgDefs.h)	(revision a28aee98cd045d638c1fb5d8ecfee61280ce55dc)
+++ MsgDefs.h	(.../MsgDefs.h)	(revision abb6a2d2ac9f42a4d195b375c9843dc45c846865)
@@ -55,6 +55,12 @@
     MSG_ID_DG_VERSION = 0x1E,                                           ///< DG f/w version.
     MSG_ID_RO_PUMP_DATA = 0x1F,                                         ///< DG broadcast of RO pump data.
     MSG_ID_DG_PRESSURES_DATA = 0x20,                                    ///< DG broadcast of pressure sensors data.
+    MSG_ID_DG_SWITCH_RESERVOIR = 0x21,                                  ///< HD request to DG to switch reservoirs (A->B or B->A).
+    MSG_ID_DG_FILL = 0x22,                                              ///< HD request to DG to fill inactive reservoir.
+    MSG_ID_DG_DRAIN = 0x23,                                             ///< HD request to DG to drain inactive reservoir.
+    MSG_ID_DRAIN_PUMP_DATA = 0x24,                                      ///< DG broadcast of drain pump data.
+    MSG_ID_HD_OP_MODE = 0x25,                                           ///< HD broadcast current operating mode.
+    MSG_ID_STARTING_STOPPING_TREATMENT = 0x26,                          ///< HD request to DG to move in/out of standby mode due to treatment start/stop.
 
     // service/test CAN messages