Fix syntax of rtps_writer

src/TODO.txt

@@ -257,7 +257,9 @@ DESIGN DECISIONS
 *   Since the "reading" side needs to have consistent state during it's processing, it does not make 
     sense to implement dual port RAMs for the History Cache.
     
-
+*   Since the RTPS Writer only gets ACKNACK Messages from the matched Readers, and these Messages are
+    dropped by the rtps_handler if samller than expected, we do not need a "READ GUARD" in the RTPS 
+    Writer.
 
 PROTOCOL UNCOMPLIANCE
 =====================

src/rtps_config_package.vhd

@@ -41,7 +41,7 @@ package rtps_config_package is
     constant OPCODE_PARTICIPANT_UNMATCH : std_logic_vector(ENDPOINT_MATCH_OPCODE_WIDTH-1 downto 0) := x"55000002";
     constant OPCODE_LIVELINESS_UPDATE   : std_logic_vector(ENDPOINT_MATCH_OPCODE_WIDTH-1 downto 0) := x"55000003";
     
-    type HISTORY_CACHE_OPCODE_TYPE is (NOP, ADD_CACHE_CHANGE, GET_CACHE_CHANGE, ACK_CACHE_CHANGE, NACK_CACHE_CHANGE, REMOVE_WRITER);
+    type HISTORY_CACHE_OPCODE_TYPE is (NOP, ADD_CACHE_CHANGE, GET_CACHE_CHANGE, ACK_CACHE_CHANGE, NACK_CACHE_CHANGE, REMOVE_CACHE_CHANGE, REMOVE_WRITER, GET_MIN_SN, GET_MAX_SN);
     type KEY_GENERATOR_OPCODE_TYPE is (NOP, WRITE_PAYLOAD, READ_KEY, READ_SIZE);
     type HISTORY_CACHE_RESPONSE_TYPE is (OK, REJECTED, INVALID, ERROR);