Index: firmware/App/Modes/ModeStandby.c
===================================================================
diff -u -r285b5d82539c96524c93703d52a66fff76fb64fc -r79c2105d7ec35f3caeb977f6e2cc1b494853d211
--- firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision 285b5d82539c96524c93703d52a66fff76fb64fc)
+++ firmware/App/Modes/ModeStandby.c	(.../ModeStandby.c)	(revision 79c2105d7ec35f3caeb977f6e2cc1b494853d211)
@@ -16,8 +16,11 @@
 ***************************************************************************/
 
 #include "AirTrap.h"
+#include "Buttons.h"
 #include "DDInterface.h"
 #include "Messaging.h"
+#include "ModeTreatment.h"
+#include "ModeTxParams.h"
 #include "ModeStandby.h"
 #include "OperationModes.h"
 
@@ -28,6 +31,9 @@
 
 // ********** private definitions **********
 
+#define USER_COMMAND_CANCEL                 0                                                  ///< Cancel treatment workflow command code.
+#define USER_COMMAND_INITIATE               1                                                  ///< Initiate treatment workflow command code.
+
 // ********** private data **********
 
 static TD_STANDBY_STATE_T currentStandbyState;                                                 ///< Current state (sub-mode) of standby mode.
@@ -42,8 +48,7 @@
  * @brief
  * The initStandbyMode function initializes the Standby Mode Unit.
  * @details \b Inputs: none
- * @details \b Outputs: currentStandbyState, treatStartReqReceived,
- * disinfectCancelReqID, homingInitiated
+ * @details \b Outputs: currentStandbyState, treatStartReqReceived
  * @return none
  *************************************************************************/
 void initStandbyMode( void )
@@ -56,8 +61,8 @@
  * @brief
  * The transitionToStandbyMode function prepares for transition to standby mode.
  * @details \b Inputs: none
- * @details \b Outputs: Standby Mode unit re-initialized, DG interface initialized,
- * blood & dialysate pumps shut off.
+ * @details \b Outputs: Standby Mode unit re-initialized, DD interface initialized,
+ * actuators off.
  * @return initial state
  *************************************************************************/
 U32 transitionToStandbyMode( void )
@@ -102,9 +107,14 @@
  *************************************************************************/
 U32 execStandbyMode( void )
 {
-//    BOOL stop = isStopButtonPressed();
+    BOOL stop = isStopButtonPressed();
 
-    // State machine to get DG to prep a reservoir so we can start a treatment
+    if ( TRUE == stop )
+    {
+        // Ignore stop button in this mode.
+    }
+
+    // State machine for standby mode
     switch ( currentStandbyState )
     {
         case STANDBY_START_STATE:
@@ -235,9 +245,9 @@
 //        PRESSURE_LIMIT_CHANGE_RESPONSE_T respRecord = { TRUE, REQUEST_REJECT_REASON_NONE, 0, 0, 0 };
 
         // Initialize treatment modes before starting a new treatment
-//        initTreatParamsMode();
+        initTreatParamsMode();
 //        initPreTreatmentMode();
-//        initTreatmentMode();
+        initTreatmentMode();
 //        initPostTreatmentMode();
         resetAirTrap();
         // Send UI default pressure settings since user is not asked to set them.
@@ -246,15 +256,74 @@
 //        respRecord.venPresLimitAsymmetricmmHg = getTreatmentParameterS32DefaultValue( TREATMENT_PARAM_VEN_PRES_LIMIT_ASYMMETRIC );
 //        sendPressureLimitsChangeResponse( &respRecord );
         // Start treatment workflow with treatment parameters mode
-//        requestNewOperationMode( MODE_TPAR );
-//        treatStartReqReceived = FALSE;
+        requestNewOperationMode( MODE_TPAR );
+        treatStartReqReceived = FALSE;
     }
 
     return state;
 }
 
 /*********************************************************************//**
  * @brief
+ * The signalUserInitiateTreatment function handles user initiation of a
+ * treatment.
+ * @details \b Inputs: none
+ * @details \b Outputs: treatStartReqReceived
+ * @param message initiate/reject treatment workflow message from UI which
+ * includes the command code (0=cancel, 1=initiate).
+ * @return TRUE if signal accepted, FALSE if not
+ *************************************************************************/
+BOOL signalUserInitiateTreatment( MESSAGE_T *message )
+{
+    BOOL result                            = FALSE;
+    U32  cmd                               = 0;
+    TD_OP_MODE_T mode                      = getCurrentOperationMode();
+    REQUEST_REJECT_REASON_CODE_T rejReason = REQUEST_REJECT_REASON_NONE;
+    UI_RESPONSE_PAYLOAD_T response;
+
+    // Verify message payload length is valid
+    if ( sizeof( U32 ) == message->hdr.payloadLen )
+    {
+        memcpy( &cmd, message->payload, sizeof( U32 ) );
+
+        if ( USER_COMMAND_INITIATE == cmd )
+        {
+            // Verify TD is in standby mode waiting for treatment start request
+            if ( ( mode != MODE_STAN ) || ( STANDBY_WAIT_FOR_TREATMENT_STATE != currentStandbyState ) )
+            {
+                rejReason = REQUEST_REJECT_REASON_NOT_ALLOWED_IN_CURRENT_MODE;
+            }
+            else
+            {
+                // If request to start treatment not rejected, set flag to initiate treatment workflow
+                result                = TRUE;
+                treatStartReqReceived = TRUE;
+            }
+        }
+        else if ( USER_COMMAND_CANCEL == cmd )
+        {
+            result = signalUserCancelTreatment();
+            if ( result != TRUE )
+            {
+                rejReason = REQUEST_REJECT_REASON_NOT_ALLOWED_IN_CURRENT_MODE;
+            }
+        }
+        else
+        {
+            rejReason = REQUEST_REJECT_REASON_INVALID_COMMAND;
+        }
+    }
+
+    // Respond to request to start treatment
+    response.accepted = result;
+    response.rejectionReason = rejReason;
+    sendMessage( MSG_ID_TD_RESP_INITIATE_TREATMENT_WORKFLOW, COMM_BUFFER_OUT_CAN_TD_2_UI, (U08*)(&response), sizeof( UI_RESPONSE_PAYLOAD_T ) );
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
  * The signalAlarmActionToStandbyMode function executes the given alarm action
  * as appropriate while in Standby Mode.
  * @details \b Inputs: none