Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r9302e1bd2413cbf99e80ac51aac38502d94801d9 -rc6f3b01d1b0a5e3fdf480a7ee205ca349e10d6d2
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 9302e1bd2413cbf99e80ac51aac38502d94801d9)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision c6f3b01d1b0a5e3fdf480a7ee205ca349e10d6d2)
@@ -25,8 +25,10 @@
 #include "DialInFlow.h"
 #include "Dialysis.h"
 #include "FPGA.h"
-#include "MessagePayloads.h"
-#include "ModeTreatment.h"
+#include "MessagePayloads.h"
+#include "ModeStandby.h"
+#include "ModeTreatment.h"
+#include "ModeTreatmentParams.h"
 #include "PresOccl.h"
 #include "SafetyShutdown.h"
 #include "SystemComm.h"
@@ -1267,7 +1269,7 @@
 
         memcpy( &payload, message->payload, sizeof(LOAD_CELL_READINGS_PAYLOAD_T) );
         result = setNewLoadCellReadings( payload.res1PrimaryLoadCell, payload.res1BackupLoadCell, payload.res2PrimaryLoadCell, payload.res2BackupLoadCell );
-    }
+    }
     // TODO - what to do if invalid payload length?
     // TODO - how to know if DG stops sending these?
 }
@@ -1410,10 +1412,132 @@
         {
             result = resumeUF();
         }
-    }
+    }
+
     sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, result );
 }
 
+/*************************************************************************
+ * @brief
+ * The handleUIStartTreatmentMsg function handles a treatment start/cancel \n
+ * message from the UI.
+ * @details
+ * Inputs : none
+ * Outputs : message handled
+ * @param message a pointer to the message to handle
+ * @return none
+ *************************************************************************/
+void handleUIStartTreatmentMsg( MESSAGE_T *message )
+{
+    BOOL result = FALSE;
+
+    if ( message->hdr.payloadLen == sizeof(U32) )
+    {
+        U32 cmd;
+
+        memcpy( &cmd, message->payload, sizeof(U32) );
+
+        if ( 0 == cmd )         // initiate treatment (go to treatment params mode)
+        {
+            result = signalUserStartingTreatment();
+        }
+        else if ( 1 == cmd )    // cancel treatment (return from aborted treatment params mode)
+        {
+            result = signalUserCancelTreatment();
+        }
+        else if ( 2 == cmd )    // start treatment
+        {
+            // TODO - handle when pre-treatment mode is ready for this
+        }
+    }
+
+    sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, result );
+}
+
+/*************************************************************************
+ * @brief
+ * The handleTreatmentParametersFromUI function handles a treatment parameters \n
+ * set and validate request message from the UI.
+ * @details
+ * Inputs : none
+ * Outputs : message handled
+ * @param message a pointer to the message to handle
+ * @return none
+ *************************************************************************/
+void handleTreatmentParametersFromUI( MESSAGE_T *message )
+{
+    if ( message->hdr.payloadLen == sizeof(TREATMENT_PARAMS_DATA_PAYLOAD_T) )
+    {
+        TREATMENT_PARAMS_DATA_PAYLOAD_T treatmentParams;
+
+        memcpy( &treatmentParams, message->payload, sizeof(TREATMENT_PARAMS_DATA_PAYLOAD_T) );
+
+        if ( FALSE == validateAndSetTreatmentParameters( treatmentParams ) )
+        {
+            sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, FALSE );
+        }
+    }
+    else
+    {
+        sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, FALSE );
+    }
+}
+
+/*************************************************************************
+ * @brief
+ * The handleUIUserConfirmTreatmentParameters function handles a user confirmation \n
+ * of treatment parameters message from the UI.
+ * @details
+ * Inputs : none
+ * Outputs : message handled
+ * @param message a pointer to the message to handle
+ * @return none
+ *************************************************************************/
+void handleUIUserConfirmTreatmentParameters( MESSAGE_T *message )
+{
+    BOOL result = FALSE;
+
+    if ( 0 == message->hdr.payloadLen )
+    {
+        result = signalUserConfirmationOfTreatmentParameters();
+    }
+
+    sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, result );
+}
+
+/*************************************************************************
+ * @brief
+ * The sendTreatmentParametersResponseMsg function constructs a treatment parameters \n
+ * response to the UI and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : Treatment parameters response msg constructed and queued.
+ * @param accepted T/F - are settings ok?
+ * @param rejectReasons reasons each parameter was rejected (if not accepted)
+ * @param byteLength number of bytes that array of reject reasons takes
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendTreatmentParametersResponseMsg( BOOL accepted, U08 *rejectReasons, U32 byteLength )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_HD_NEW_TREATMENT_PARAMS_RESPONSE;
+    msg.hdr.payloadLen = sizeof( BOOL ) + byteLength;
+
+    memcpy( payloadPtr, &accepted, sizeof( BOOL ) );
+    payloadPtr += sizeof( BOOL );
+    memcpy( payloadPtr, rejectReasons, byteLength );
+
+    // 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_UI, ACK_REQUIRED );
+
+    return result;
+}
+
 /*************************************************************************
  * @brief
  * The handleChangeUFSettingsRequest function handles a ultrafiltration \n
@@ -1701,6 +1825,7 @@
     if ( ( 3 == message->hdr.payloadLen ) && ( 0x31 == message->payload[ 0 ] ) && ( 0x32 == message->payload[ 1 ] ) && ( 0x33 == message->payload[ 2 ] ) )
     {
         testerLoggedIn = TRUE;
+        checkInFromUI();  // allow tasks to begin normal processing when tester has logged in
     }
     else
     {