Index: firmware/App/Modes/ModeFlush.c
===================================================================
diff -u -r499e5de29e706d09f79ba22511068990c4044e84 -rc48a99d2d1c852adcc986253b6c420a90dab7bfe
--- firmware/App/Modes/ModeFlush.c	(.../ModeFlush.c)	(revision 499e5de29e706d09f79ba22511068990c4044e84)
+++ firmware/App/Modes/ModeFlush.c	(.../ModeFlush.c)	(revision c48a99d2d1c852adcc986253b6c420a90dab7bfe)
@@ -1,4 +1,4 @@
-/**************************************************************************
+/**********************************************************************//**
  *
  *  Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
  *
@@ -8,7 +8,7 @@
  *  @file ModeFlush.c
  *
  *  @date 20-Dec-2019
- *  @author L. Baloa
+ *  @author S. Nash
  *
  *  @brief Top-level state machine for flush mode.
  *
@@ -17,47 +17,74 @@
 #include "ModeFlush.h"
 #include "OperationModes.h"
 
+/**
+ *  @addtogroup FlushMode
+ *  @{
+ */
+
+// ********** private definitions **********
+
+/// Enumeration of flush mode states.
+typedef enum Flush_States
+{
+    FLUSH_STATE_START = 0,                               ///< Start flush mode state.
+    NUM_OF_FLUSH_STATES                                  ///< Number of flush mode states.
+} FLUSH_STATE_T;
+
 // ********** private data **********
 
+static FLUSH_STATE_T flushState = FLUSH_STATE_START;     ///< Currently active flush state.
+
 // ********** private function prototypes **********
 
-/*************************************************************************
- * @brief initFlushMode
+/*********************************************************************//**
+ * @brief
  * The initFlushMode function initializes flush Mode module.
  * @details
  * Inputs : none
  * Outputs : none
- * @param none
  * @return none
 *************************************************************************/
 void initFlushMode( void )
 {
+    flushState = FLUSH_STATE_START;
 }
 
-/*************************************************************************
- * @brief transitionToFlushMode
+/*********************************************************************//**
+ * @brief
  * The transitionToFlushMode function prepares for transition to \n
  * flush mode.
  * @details
  * Inputs : none
  * Outputs :
- * @param none
  * @return none
 *************************************************************************/
 void transitionToFlushMode( void )
 {
+    initFlushMode();
 }
 
-/*************************************************************************
- * @brief execFlushMode
+/*********************************************************************//**
+ * @brief
  * The execFlushMode function executes the flush Mode state machine.
  * @details
  * Inputs : none
  * Outputs :
- * @param none
  * @return none
 *************************************************************************/
 void execFlushMode( void )
 {
+    // execute current flush state
+    switch ( flushState )
+    {
+        case FLUSH_STATE_START:
+            break;
+
+        default:
+            flushState = FLUSH_STATE_START;
+            // TODO - s/w fault
+            break;
+    }
 }
 
+/**@}*/