Index: App/Services/SystemComm.c
===================================================================
diff -u -ree310a2e5262c05bf0dc0eb0d84da0ee50bac7fe -r7d70e839bc71f6fc37da8cd12eecb374841882df
--- App/Services/SystemComm.c	(.../SystemComm.c)	(revision ee310a2e5262c05bf0dc0eb0d84da0ee50bac7fe)
+++ App/Services/SystemComm.c	(.../SystemComm.c)	(revision 7d70e839bc71f6fc37da8cd12eecb374841882df)
@@ -16,14 +16,29 @@
  *
  **************************************************************************/
 
+#include "can.h"
+
 #include "Common.h"
+#include "Buttons.h"
+#include "CommBuffers.h"
+#include "MsgQueues.h"
 #include "SystemComm.h"
 
 // ********** private definitions **********
 
+typedef enum Msg_IDs
+{
+    MSG_ID_TEST = 0,
+    MSG_ID_OFF_BUTTON_PRESS,
+    NUM_OF_MSG_IDS
+} MSG_ID_T;
+
 // ********** private data **********
 
 
+// ********** private function prototypes **********
+
+
 /*************************************************************************
  * @brief initSystemComm
  * The initSystemComm function initializes the SystemComm module.
@@ -35,6 +50,96 @@
  *************************************************************************/
 void initSystemComm( void )
 {
+
 }
 
+/*************************************************************************
+ * @brief initSystemComm
+ * The initSystemComm function initializes the SystemComm module.
+ * @details
+ * Inputs : none
+ * Outputs : SystemComm module initialized.
+ * @param none
+ * @return none
+ *************************************************************************/
+void execSystemComm( void )
+{
+    // TODO - this is ugly preliminary test code - nowhere near ready for code review
+    BOOL isThereMsgToXmit;
+    BOOL isThereMsgRcvd;
+    U08  data[sizeof(MESSAGE_WRAPPER_T)];
+    U32 dataSize;
+    MESSAGE_WRAPPER_T msg;
 
+    // get next msg to transmit to UI
+    isThereMsgToXmit = getFromMsgQueue( MSG_Q_CAN_HD_2_UI, &msg );
+    if ( TRUE == isThereMsgToXmit )
+    {
+        U08 *dataPtr = data;
+
+        memcpy( dataPtr, &(msg.msg.hdr), sizeof(MESSAGE_HEADER_T) );
+        memcpy( dataPtr+sizeof(MESSAGE_HEADER_T), &(msg.msg.cargo), msg.msg.hdr.cargoLen );
+        memcpy( dataPtr+(sizeof(MESSAGE_HEADER_T) + msg.msg.hdr.cargoLen), &(msg.crc), sizeof(U08) );
+
+        addToCommBuffer( COMM_BUFFER_CAN_HD_2_UI, dataPtr, MESSAGE_OVERHEAD_SIZE + msg.msg.hdr.cargoLen );
+    }
+
+    // actually transmit any pending messages
+    dataSize = getFromCommBuffer( COMM_BUFFER_CAN_HD_2_UI, data, sizeof(MESSAGE_WRAPPER_T) );
+    if ( dataSize <= 8 )
+    {
+        canTransmit( canREG1, canMESSAGE_BOX1, data );
+    }
+
+    // queue any received CAN messages
+    if ( FALSE != canIsRxMessageArrived( canREG1, canMESSAGE_BOX2 ) )
+    {
+        MESSAGE_WRAPPER_T rcvMsg;
+        U08 *dataPtr = data;
+
+        canGetData( canREG1, canMESSAGE_BOX2, data );
+        blankMessageInWrapper( &rcvMsg );
+        memcpy( &(rcvMsg.msg.hdr), dataPtr, sizeof(MESSAGE_HEADER_T) );
+        memcpy( &(rcvMsg.msg.cargo), dataPtr+sizeof(MESSAGE_HEADER_T), rcvMsg.msg.hdr.cargoLen );
+        memcpy( &(rcvMsg.crc), dataPtr+(sizeof(MESSAGE_HEADER_T)+rcvMsg.msg.hdr.cargoLen), sizeof(U08) );
+        addToMsgQueue( MSG_Q_CAN_UI_2_HD, &rcvMsg );
+    }
+
+    // see if any messages received
+    isThereMsgRcvd = getFromMsgQueue( MSG_Q_CAN_UI_2_HD, &msg );
+    if ( TRUE == isThereMsgRcvd )
+    {
+        switch ( msg.msg.hdr.msgID )
+        {
+            case MSG_ID_OFF_BUTTON_PRESS:
+                userConfirmOffButton();
+                break;
+            default:
+                break;
+        }
+    }
+}
+
+/*************************************************************************
+ * @brief sendOffButtonMsgToUI
+ * The sendOffButtonMsgToUI function constructs an off button msg to the UI \n
+ * and queues the msg for transmit on the appropriate CAN channel.
+ * @details
+ * Inputs : none
+ * Outputs : Off button msg constructed and queued.
+ * @param none
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendOffButtonMsgToUI( void )
+{
+    BOOL result;
+    MESSAGE_WRAPPER_T msg;
+
+    blankMessageInWrapper( &msg );
+    msg.msg.hdr.msgID = MSG_ID_OFF_BUTTON_PRESS;
+    msg.msg.hdr.cargoLen = 0;
+    result = addToMsgQueue( MSG_Q_CAN_HD_2_UI, &msg );
+
+    return result;
+}
+