Index: firmware/App/Services/Reservoirs.c
===================================================================
diff -u -rf43eb1e9e0803776ec7420b16e1db8760b020bd9 -r5a61bccd959265c00e5276ba23391198ca82b6dd
--- firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision f43eb1e9e0803776ec7420b16e1db8760b020bd9)
+++ firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 5a61bccd959265c00e5276ba23391198ca82b6dd)
@@ -61,31 +61,39 @@
     drainVolumeTargetMl.data = DEFAULT_DRAIN_VOLUME_ML;
 }
 
+BOOL setActiveReservoir( RESERVOIR_ID_T resID )
+{
+    // switch reservoir command only valid in re-circulate mode
+    if ( MODE_CIRC == getCurrentOperationMode() )
+    {
+        // validate parameters
+        if ( resID < NUM_OF_RESERVOIRS )
+        {
+            activeReservoir.data = (U32)resID;
+        }
+    }
+}
+
 /*********************************************************************//**
  * @brief
  * The startFill function handles a fill command from the HD.
  * @details
  * Inputs : none
  * Outputs : move to fill mode
- * @param resID : Reservoir to drain.
  * @param fillToVolMl : Target volume (in mL) to fill reservoir to.
- * @param targetPrimeTemp : Target temperature of dialysate to fill reservoir with.
- * @param targetTrimTemp : Target temperature of dialysate coming out of reservoir.
  * @return TRUE if fill command successful, FALSE if not.
  *************************************************************************/
-BOOL startFill( RESERVOIR_ID_T resID, U32 fillToVolMl, F32 targetPrimeTemp, F32 targetTrimTemp )
+BOOL startFill( U32 fillToVolMl )
 {
     BOOL result = FALSE;
 
-    // fill command only valid in standby mode
-    if ( MODE_STAN == getCurrentOperationMode() )
+    // fill command only valid in re-circulate mode
+    if ( MODE_CIRC == getCurrentOperationMode() )
     {
         // validate parameters
-        if ( ( resID < NUM_OF_RESERVOIRS ) && ( fillToVolMl < MAX_FILL_VOLUME_ML ) )
+        if ( fillToVolMl < MAX_FILL_VOLUME_ML )
         {
-            activeReservoir.data = (U32)resID;
             fillVolumeTargetMl.data = fillToVolMl;
-            // TODO - relay temperature targets to the heater controller module
             requestNewOperationMode( MODE_FILL );
         }
     }
@@ -108,7 +116,7 @@
     // stop fill command only valid in fill mode
     if ( MODE_FILL == getCurrentOperationMode() )
     {
-        requestNewOperationMode( MODE_STAN );
+        requestNewOperationMode( MODE_CIRC );
     }
 
     return result;
@@ -120,22 +128,19 @@
  * @details
  * Inputs : none
  * Outputs :
- * @param resID : Reservoir to drain.
  * @param drainToVolMl : Target volume (in mL) to drain reservoir to.
  * @return TRUE if drain command successful, FALSE if not.
  *************************************************************************/
-BOOL startDrain( RESERVOIR_ID_T resID, U32 drainToVolMl )
+BOOL startDrain( U32 drainToVolMl )
 {
     BOOL result = FALSE;
 
-    // drain command only valid in standby mode
-    if ( MODE_STAN == getCurrentOperationMode() )
+    // drain command only valid in re-circulate mode
+    if ( MODE_CIRC == getCurrentOperationMode() )
     {
         // validate parameters
-        if ( ( resID < NUM_OF_RESERVOIRS ) &&
-             ( drainToVolMl > MIN_DRAIN_VOLUME_ML ) && ( drainToVolMl < MAX_DRAIN_VOLUME_ML ) )
+        if ( ( drainToVolMl > MIN_DRAIN_VOLUME_ML ) && ( drainToVolMl < MAX_DRAIN_VOLUME_ML ) )
         {
-            activeReservoir.data = (U32)resID;
             drainVolumeTargetMl.data = drainToVolMl;
             requestNewOperationMode( MODE_DRAI );
         }
@@ -159,7 +164,7 @@
     // stop drain command only valid in drain mode
     if ( MODE_DRAI == getCurrentOperationMode() )
     {
-        requestNewOperationMode( MODE_STAN );
+        requestNewOperationMode( MODE_CIRC );
     }
 
     return result;