Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -rbbea4a2a607ed759bc283c75623c0e3f9a8c066c -ra19a676d1e67bb3e1aca9e9bba49727f9d5f8b38
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision bbea4a2a607ed759bc283c75623c0e3f9a8c066c)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision a19a676d1e67bb3e1aca9e9bba49727f9d5f8b38)
@@ -118,7 +118,7 @@
 
 typedef struct
 {
-    U32 resID;
+    DG_RESERVOIR_ID_T resID;
     U32 setFillToVolumeMl;
     U32 setDrainToVolumeMl;
 } DG_RESERVOIRS_DATA_PAYLOAD_T;
@@ -522,6 +522,147 @@
 }
 
 /*************************************************************************
+ * @brief
+ * The sendDGSwitchReservoirCommand function constructs a DG set active \n
+ * reservoir message for DG and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : DG set active reservoir msg constructed and queued.
+ * @param activeReservoir : reservoir ID to set as active.
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendDGSwitchReservoirCommand( DG_RESERVOIR_ID_T activeReservoir )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_DG_SWITCH_RESERVOIR_CMD;
+    msg.hdr.payloadLen = sizeof( DG_RESERVOIR_ID_T );
+
+    memcpy( payloadPtr, &activeReservoir, sizeof( DG_RESERVOIR_ID_T ) );
+
+    // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_DG, ACK_REQUIRED );
+
+    return result;
+}
+
+/*************************************************************************
+ * @brief
+ * The sendDGFillCommand function constructs a DG fill command message \n
+ * and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : DG fill command msg constructed and queued.
+ * @param fillToVolumeMl : volume (in mL) to fill inactive reservoir to.
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendDGFillCommand( U32 fillToVolumeMl )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_DG_FILL_CMD;
+    msg.hdr.payloadLen = sizeof( U32 );
+
+    memcpy( payloadPtr, &fillToVolumeMl, sizeof( U32 ) );
+
+    // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_DG, ACK_REQUIRED );
+
+    return result;
+}
+
+/*************************************************************************
+ * @brief
+ * The sendDGDrainCommand function constructs a DG drain command message \n
+ * and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : DG drain command msg constructed and queued.
+ * @param drainToVolumeMl : volume (in mL) to drain the inactive reservoir to.
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendDGDrainCommand( U32 drainToVolumeMl )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_DG_DRAIN_CMD;
+    msg.hdr.payloadLen = sizeof( U32 );
+
+    memcpy( payloadPtr, &drainToVolumeMl, sizeof( U32 ) );
+
+    // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_DG, ACK_REQUIRED );
+
+    return result;
+}
+
+/*************************************************************************
+ * @brief
+ * The sendDGStartStopCommand function constructs a DG start/stop command \n
+ * message and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : DG start/stop command msg constructed and queued.
+ * @param start : TRUE indicates start DG, FALSE indicates stop DG.
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendDGStartStopCommand( BOOL start )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_STARTING_STOPPING_TREATMENT_CMD;
+    msg.hdr.payloadLen = sizeof( BOOL );
+
+    memcpy( payloadPtr, &start, sizeof( BOOL ) );
+
+    // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_DG, ACK_REQUIRED );
+
+    return result;
+}
+
+/*************************************************************************
+ * @brief
+ * The sendDGSampleWaterCommand function constructs a DG sample water command \n
+ * message and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : DG sample water command msg constructed and queued.
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendDGSampleWaterCommand( void )
+{
+    BOOL result;
+    MESSAGE_T msg;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_DG_SAMPLE_WATER_CMD;
+    msg.hdr.payloadLen = 0;
+
+    // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_DG, ACK_REQUIRED );
+
+    return result;
+}
+
+/*************************************************************************
  * @brief broadcastAlarmStatus
  * The broadcastAlarmStatus function constructs an alarm status msg to \n
  * be broadcast and queues the msg for transmit on the appropriate CAN channel.