Index: firmware/App/Services/SystemComm.c
===================================================================
diff -u -rd4f40c48a728c866c24bf44a59ff8ddd1e244ca1 -r76fc4506fd38ea6bd317abbaaf85db5aa589a7cc
--- firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision d4f40c48a728c866c24bf44a59ff8ddd1e244ca1)
+++ firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 76fc4506fd38ea6bd317abbaaf85db5aa589a7cc)
@@ -7,8 +7,8 @@
 *
 * @file    SystemComm.c
 *
-* @author  (last)      Dara Navaei
-* @date    (last)      26-Apr-2023
+* @author  (last)      Sean Nash
+* @date    (last)      24-Aug-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -106,6 +106,7 @@
 static U32 canXmitRetryCtr = 0;                                             ///< counter for CAN transmit retries.
 static OVERRIDE_U32_T hdCommunicationStatus = {0, 0, 0, 0};                 ///< has HD sent a message since last check
 static volatile U32 timeOfLastHDCheckIn = 0;                                ///< last time we received an HD broadcast
+static OVERRIDE_U32_T pendingACKOverride = { 0, 0, 0, 0 };                  ///< Pending ACK override data structure.
 
 // ********** private function prototypes **********
 
@@ -160,7 +161,7 @@
  *************************************************************************/
 BOOL isHDCommunicating( void )
 {
-    return getU32OverrideValue(&hdCommunicationStatus);
+    return getU32OverrideValue( &hdCommunicationStatus );
 }
 
 /*********************************************************************//**
@@ -668,6 +669,7 @@
     if ( TRUE == didTimeout( timeOfLastHDCheckIn, HD_COMM_TIMEOUT_IN_MS ) )
     {
         hdCommunicationStatus.data = FALSE;
+        setHDOperationMode( 0, 0 );   // If HD off or not connected, consider HD mode is fault.
     }
 }
 
@@ -780,7 +782,7 @@
     {
         for ( i = 0; i < PENDING_ACK_LIST_SIZE; i++ )
         {   // pending ACK expired?
-            if ( ( TRUE == pendingAckList[ i ].used ) && ( TRUE == didTimeout( pendingAckList[ i ].timeStamp, MSG_NOT_ACKED_TIMEOUT_MS ) ) )
+            if ( ( TRUE == pendingAckList[ i ].used ) && ( ( TRUE == didTimeout( pendingAckList[ i ].timeStamp, MSG_NOT_ACKED_TIMEOUT_MS ) ) ||  ( getU32OverrideValue( &pendingACKOverride ) > 0 ) ) )
             {   // if retries left, reset and resend pending message. Do not retry when in POST since the UI might not still be responsive
                 if ( pendingAckList[ i ].retries > 0 )
                 {
@@ -881,6 +883,10 @@
             handleHDStartStopTrimmerHeaterCmd( message );
             break;
 
+        case MSG_ID_DG_PARK_CONCENTRATE_PUMPS_CMD_REQUEST:
+            handleParkConecentratePumpsCmd( message );
+            break;
+
         case MSG_ID_DG_START_STOP_TRIMMER_HEATER_CMD:
             handleDGStartStopTrimmerHeater( message );
             break;
@@ -909,8 +915,8 @@
             handleDGPOSTResultRequest( message );
             break;
 
-        case MSG_ID_HD_DG_SERVICE_RECORD_REQUEST:
-            handleDGServiceScheduleRequest( message );
+        case MSG_ID_UI_SERVICE_INFO_REQUEST:
+            handleDGServiceScheduleRequestToUI( message );
             break;
 
         case MSG_ID_HD_DG_CONCENTRATE_MIXING_RATIOS_REQUEST:
@@ -937,14 +943,26 @@
             handleResendAllAlarmsCommand( message );
             break;
 
+        case MSG_ID_UI_SET_DG_RO_MODE:
+            handleSetROOnlyMode( message );
+            break;
+
         case MSG_ID_HD_SEND_CHEM_FLUSH_SAMPLE_PASS_FAIL_TO_DG:
             handleReceiveChemFlushSampleResultsFromHD( message );
             break;
 
-        case MSG_ID_UI_SET_DG_RO_MODE:
-            handleSetROOnlyMode( message );
+        case MSG_ID_DG_START_STOP_RO_PERMEATE_SAMPLE_MODE_CMD_REQUEST:
+            handleStartStopDGROPermeateSample( message );
             break;
 
+        case MSG_ID_HD_SEND_RO_PERMEATE_SAMPLE_DISPENSE_REQUEST_TO_DG:
+            handleReceiveROPermeatSampleDispenseRequest( message );
+            break;
+
+        case MSG_ID_HD_REQUEST_SERVICE_RECORD_FROM_HD:
+            handleSendDGServiceRecordToHD( message );
+            break;
+
         // NOTE: This case must be last
         case MSG_ID_DG_TESTER_LOGIN_REQUEST:
             handleTesterLogInRequest( message );
@@ -1016,7 +1034,7 @@
                 handleTestValveStateOverrideRequest( message );
                 break;
 
-            case MSG_ID_VALVES_STATES_PUBLISH_INTERVAL_OVERRIDE:
+            case MSG_ID_DG_VALVES_STATES_PUBLISH_INTERVAL_OVERRIDE:
                 handleTestValvesStatesPublishIntervalOverrideRequest( message );
                 break;
 
@@ -1212,13 +1230,15 @@
                 handleTestUsedBicarbVolumeMLOverrideRequest( message );
                 break;
 
+#ifndef _RELEASE_
             case MSG_ID_DG_GET_SW_CONFIG_RECORD:
                 handleGetDGSoftwareConfigRecord( message );
                 break;
 
             case MSG_ID_DG_SET_SW_CONFIG_RECORD:
                 handleSetDGSoftwareConfigRecord( message );
                 break;
+#endif
 
             case MSG_ID_DG_FANS_DUTY_CYCLE_OVERRIDE:
                 handleSetFansDutyCycleOverrideRequest( message );
@@ -1338,6 +1358,30 @@
                 handleTestDGSetConductivitySensorCalTable( message );
                 break;
 
+            case MSG_ID_DG_SIGNAL_RECOVER_FROM_FAULT_MODE:
+                handleTestDGSetRecoverFromFaultModeSignal( message );
+                break;
+
+            case MSG_ID_DG_DRAIN_MODE_BROADCAST_INTERVAL_OVERRIDE:
+                handleTestDGDrainModeBroadcastOverrideRequest( message );
+                break;
+
+            case MSG_ID_DG_DIALIN_RO_ONLY_MODE_STATUS_REQUEST:
+                handleDGROStatusRequest( message );
+                break;
+
+            case MSG_ID_DG_RAM_STATUS_OVERRIDE:
+                handleTestDGRAMStatusOverrideRequest( message );
+                break;
+
+            case MSG_ID_DG_RESERVOIR_BROADCAST_INTERVAL_OVERRIDE:
+                handleTestDGReservoirOverrideRequest( message );
+                break;
+
+            case MSG_ID_DG_CAN_RECEIVE_ACK_MESSAGE_OVERRIDE:
+                handleTestDGPendingACKOverrideRequest( message );
+                break;
+
             default:
                 // TODO - unrecognized message ID received - ignore
                 break;
@@ -1395,4 +1439,48 @@
     return result;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The testSetPendingACKOverride function overrides the
+ * pendingACKOverride variable.
+ * @details Inputs: none
+ * @details Outputs: pendingACKOverride
+ * @param value override for pendingACKOverride
+ * @return TRUE if override successful, FALSE if not
+ *************************************************************************/
+BOOL testSetPendingACKOverride( U32 value )
+{
+    BOOL result = FALSE;
+
+    if ( TRUE == isTestingActivated() )
+    {
+        result = TRUE;
+        pendingACKOverride.ovData = value;
+        pendingACKOverride.override = OVERRIDE_KEY;
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The testResetPendingACKOverride function resets the override
+ * of the pendingACKOverride variable.
+ * @details Inputs: none
+ * @details Outputs: pendingACKOverride
+ * @return TRUE if override reset successful, FALSE if not
+ *************************************************************************/
+BOOL testResetPendingACKOverride( void )
+{
+    BOOL result = FALSE;
+
+    if ( TRUE == isTestingActivated() )
+    {
+        result = TRUE;
+        pendingACKOverride.override = OVERRIDE_RESET;
+        pendingACKOverride.ovData = pendingACKOverride.ovInitData;
+    }
+
+    return result;
+}
 /**@}*/