Index: firmware/App/Services/SystemComm.h
===================================================================
diff -u -r359cf587f2f935ef9f40a16d17c4105efa653c1d -rab304e2ca6e3e40ed8cb12650e9855ae0b9649d8
--- firmware/App/Services/SystemComm.h	(.../SystemComm.h)	(revision 359cf587f2f935ef9f40a16d17c4105efa653c1d)
+++ firmware/App/Services/SystemComm.h	(.../SystemComm.h)	(revision ab304e2ca6e3e40ed8cb12650e9855ae0b9649d8)
@@ -7,51 +7,57 @@
 *
 * @file SystemComm.h
 *
-* @author (last) Sean
-* @date (last) 27-Feb-2020
+* @author (last) Quang Nguyen
+* @date (last) 24-Aug-2020
 *
 * @author (original) Dara Navaei
 * @date (original) 05-Nov-2019
 *
 ***************************************************************************/
+
+#ifndef __SYSTEM_COMM_H__
+#define __SYSTEM_COMM_H__
+
+#include "DGCommon.h"
+#include "CommBuffers.h"
+#include "MsgQueues.h"
+
+/**
+ *  @defgroup SystemComm SystemComm
+ *  @brief System communication module. Manages incoming and outgoing CAN frames.
+ *
+ *  @addtogroup SystemComm
+ *  @{
+ */
 
-#ifndef __SYSTEM_COMM_H__
-#define __SYSTEM_COMM_H__
+// ********** public definitions **********
+
+#define MESSAGE_SYNC_BYTE           0xA5                                                                ///< Denali message syncronization byte.
+
+#define CAN_MESSAGE_PAYLOAD_SIZE    8                                                                   ///< CAN frame payload size (in bytes).
+#ifdef DEBUG_ENABLED
+    #define PC_MESSAGE_PACKET_SIZE  8
+#endif
+
+#define MSG_ID_ACK                  0xFFFF                                                              ///< Denali message ID for acknowledging received messages (when required).
+#define MSG_ACK_BIT                 0x8000                                                              ///< ACK bit in sequence number that indicates an ACK is required.
+#define MAX_MSG_SEQ_NO              0x7FFF                                                              ///< Maximum sequence number for Denali message (then wraps to 1).
+#define MIN_MSG_SEQ_NO              0x0001                                                              ///< Minimum sequence number for Denali message.
+#define MAX_ACK_MSG_SIZE            ( sizeof( MESSAGE_WRAPPER_T ) + 1 + CAN_MESSAGE_PAYLOAD_SIZE )      ///< Maximum size (in bytes) of Denali message including full (wrapped) message + sync + any CAN padding)
 
-#include "DGCommon.h"
-#include "CommBuffers.h"
-#include "MsgQueues.h"
+typedef COMM_BUFFER_T   CAN_MESSAGE_BOX_T;                                                              ///< the CAN comm buffers align with the active CAN message boxes
+
+// ********** public function prototypes **********
+
+void initSystemComm( void );
+void execSystemCommRx( void );
+void execSystemCommTx( void );
+void handleCANMsgInterrupt( CAN_MESSAGE_BOX_T srcCANBox );
+#ifdef DEBUG_ENABLED
+    void handleUARTMsgRecvPacketInterrupt( void );
+    void handleUARTMsgXmitPacketInterrupt( void );
+#endif
 
-// ********** public definitions **********
-
-#define MESSAGE_SYNC_BYTE           0xA5
-
-#define CAN_MESSAGE_PAYLOAD_SIZE    8
-#ifdef DEBUG_ENABLED
-    #define PC_MESSAGE_PACKET_SIZE  8
-#endif
-
-#define MSG_ID_ACK                  0xFFFF
-#define MSG_ACK_BIT                 0x8000
-#define MAX_MSG_SEQ_NO              0x7FFF
-#define MIN_MSG_SEQ_NO              0x0001
-#define MAX_ACK_MSG_SIZE            ( sizeof( MESSAGE_WRAPPER_T ) + 1 + CAN_MESSAGE_PAYLOAD_SIZE )  // must hold full (wrapped) message + sync + any CAN padding
-
-typedef COMM_BUFFER_T   CAN_MESSAGE_BOX_T;       // the first 12 comm buffers align with the 12 active CAN message boxes
-
-// ********** public function prototypes **********
-
-void initSystemComm( void );
-void execSystemCommRx( void );
-void execSystemCommTx( void );
-void handleCANMsgInterrupt( CAN_MESSAGE_BOX_T srcCANBox );
-#ifdef DEBUG_ENABLED
-    void handleUARTMsgRecvPacketInterrupt( void );
-    void handleUARTMsgXmitPacketInterrupt( void );
-#endif
-BOOL isHDCommunicating( void );
-BOOL addMsgToPendingACKList( MESSAGE_T *msg, COMM_BUFFER_T channel, U08 *msgData, U32 len );
-
 BOOL isCANBoxForXmit( CAN_MESSAGE_BOX_T srcCANBox );
 BOOL isCANBoxForRecv( CAN_MESSAGE_BOX_T srcCANBox );