diff --git a/datalink814_ge/src/linklayer/linklayer814.c b/datalink814_ge/src/linklayer/linklayer814.c
index f1ad3ea..834777a 100644
--- a/datalink814_ge/src/linklayer/linklayer814.c
+++ b/datalink814_ge/src/linklayer/linklayer814.c
@@ -651,12 +651,14 @@ L1_FRAME_TYPE L2_L2frame2L1frame(L2_FRAME_TYPE l2Frame)
 	}
 }
 #endif
+
 /*****************************************************************************/
 /**
  * @brief   Initialize link layer fsm instance, allocate memory to storage fsm
  *          data. Apply the default values to fsm.
  *
  * @param   instPtr	a pointer to physical layer controller instance
+ * @param	config a pointer to configurations
  *
  * @return  SUCCESS
  *          Other error code.
@@ -821,6 +823,18 @@ error:
 	return Status;
 }
 
+/*****************************************************************************/
+/**
+ * @brief   Reconfigure link layer instance, reset all segment and reconfigure
+ * 			accordingly.
+ *
+ * @param   instPtr	a pointer to physical layer controller instance
+ * @param	config a pointer to configurations
+ *
+ * @return  SUCCESS
+ *          Other error code.
+ *
+ ******************************************************************************/
 int32_t Linklayer_Reconfig(L2_INST *instPtr, const L2_CONFIG *config)
 {
 	ASSERT(instPtr != NULL);
@@ -888,6 +902,15 @@ int32_t Linklayer_Reconfig(L2_INST *instPtr, const L2_CONFIG *config)
 	return SUCCESS;
 }
 
+/*****************************************************************************/
+/**
+ * @brief   Completely destroy link layer instance, free all allocated memory.
+ *
+ * @param   instPtr	a pointer to physical layer controller instance
+ *
+ * @return  NONE
+ *
+ ******************************************************************************/
 void Linklayer_Destroy(L2_INST *instPtr)
 {
 	ASSERT(instPtr != NULL);
@@ -907,6 +930,15 @@ void Linklayer_Destroy(L2_INST *instPtr)
 	free(instPtr);
 }
 
+/*****************************************************************************/
+/**
+ * @brief   Start link layer processing.
+ *
+ * @param   instPtr	a pointer to physical layer controller instance
+ *
+ * @return  NONE
+ *
+ ******************************************************************************/
 int32_t Linklayer_Start(L2_INST *instPtr)
 {
 	ASSERT(instPtr != NULL);
@@ -915,6 +947,15 @@ int32_t Linklayer_Start(L2_INST *instPtr)
 	return SUCCESS;
 }
 
+/*****************************************************************************/
+/**
+ * @brief   Halt link layer.
+ *
+ * @param   instPtr	a pointer to physical layer controller instance
+ *
+ * @return  NONE
+ *
+ ******************************************************************************/
 int32_t Linklayer_Halt(L2_INST *instPtr)
 {
 	ASSERT(instPtr != NULL);