Index: App/Services/CommBuffers.c
===================================================================
diff -u -r6dde2145782d8f68eb66e053f1db8f8847b15980 -ra87b6b9e253c6c0fcc84bca6f5de71959ce18bcc
--- App/Services/CommBuffers.c	(.../CommBuffers.c)	(revision 6dde2145782d8f68eb66e053f1db8f8847b15980)
+++ App/Services/CommBuffers.c	(.../CommBuffers.c)	(revision a87b6b9e253c6c0fcc84bca6f5de71959ce18bcc)
@@ -38,7 +38,6 @@
 
 static U32 switchDoubleBuffer( COMM_BUFFER_T buffer );
 static void getDataFromInactiveBuffer( COMM_BUFFER_T buffer, U08 *data, U32 len );
-static U32 getRemainingByteCapacity( COMM_BUFFER_T buffer );
 
 /*************************************************************************
  * @brief initCommBuffers
@@ -72,8 +71,7 @@
  * @brief addToCommBuffer
  * The addToCommBuffer function adds data of specified length to a specified \n
  * communication buffer.  S/W fault if buffer too full to add data. \n
- * Only one function in one thread should be calling this function for a \n
- * given buffer.  This function will always add to the active double buffer.
+ * This function will always add to the active double buffer. \n
  * @details
  * Inputs : commBufferByteCount[], activeDoubleBuffer[]
  * Outputs : commBuffers[], commBufferByteCount[]
@@ -90,31 +88,38 @@
     // verify given buffer
     if ( buffer < NUM_OF_COMM_BUFFERS )
     {
+        U32 currentActiveBufCount;  // where to start adding new data to buffer (after existing data)
+
+        // add requires brief thread protection because there may be multiple sources for transmits trying to add data to a buffer.
+        _disable_IRQ();
+
+        currentActiveBufCount = commBufferByteCount[buffer][activeBuffer];
+
         // check to make sure buffer is not too full to service this add
-        if ( len <= getRemainingByteCapacity( buffer ) )
+        if ( len <= ( COMM_BUFFER_LENGTH - currentActiveBufCount ) )
         {
             U08 *buffPtr;  // buffer destination for added data
             U08 *srcPtr;   // data source
-            U32 dstIndex;  // where to start adding bytes in destination buffer
-            U32 i;
 
-            // get destination pointer to first available byte in buffer
-            dstIndex = commBufferByteCount[buffer][activeBuffer];
-            buffPtr = &commBuffers[buffer][activeBuffer][dstIndex];
+            // adjust buffer count per this data add (also reserves space to add data before releasing thread protection)
+            commBufferByteCount[buffer][activeBuffer] += len;
+            // release thread protection
+            _enable_IRQ();
+            // set destination pointer to end of active buffer data
+            buffPtr = &commBuffers[buffer][activeBuffer][currentActiveBufCount];
             // get source pointer to start of given data array
             srcPtr = data;
             // copy source data to destination buffer
-            for ( i = 0; i < len; i++ )
-            {
-                *buffPtr++ = *srcPtr++;
-            }
+            memcpy( buffPtr, srcPtr, len );
             // adjust buffer count per this data add
             commBufferByteCount[buffer][activeBuffer] += len;
             // data successfully added to buffer
             result = TRUE;
         }
         else // buffer too full to add this much data
         {
+            // release thread protection
+            _enable_IRQ();
             // TODO - s/w fault?
         }
     }
@@ -132,7 +137,7 @@
  * number of bytes from a given buffer and returns the number of bytes \n
  * retrieved from the buffer. This function will draw from the inactive \n
  * double buffer first and, if needed, switch double buffers to draw the \n
- * reset of the requested data.
+ * rest of the requested data.
  * Only one function in one thread should be calling this function for a given \n
  * buffer.
  * @details
@@ -245,7 +250,6 @@
     return numOfBytesPeeked;
 }
 
-
 /*************************************************************************
  * @brief numberOfBytesInCommBuffer
  * The numberOfBytesInCommBuffer function determines how many bytes \n
@@ -336,23 +340,4 @@
     }
 }
 
-/*************************************************************************
- * @brief getRemainingByteCapacity
- * The getRemainingByteCapacity function determines the remaining capacity \n
- * of the given buffer.
- * @details
- * Inputs : commBufferByteCount[], activeDoubleBuffer[]
- * Outputs : none
- * @param buffer : which comm buffer to check the capacity of
- * @return the number of bytes of capacity remaining in the buffer.
- *************************************************************************/
-static U32 getRemainingByteCapacity( COMM_BUFFER_T buffer )
-{
-    U32 result;
-    U32 activeBuffer = activeDoubleBuffer[buffer];
 
-    result = COMM_BUFFER_LENGTH - commBufferByteCount[buffer][activeBuffer];
-
-    return result;
-}
-