text: <s>[INST] Could I communicate from a SCADA Software (PC Vue, Citect) with an 1769-L30ER CPU with OPC UA? The SCADA software is the client and the PLC is the server. Does the 1769-L30ER CPU need a special firmware? [/INST] The SCADA software  (PC Vue, Citect) has built-in drivers for communications to the 1769-L30ER CPU so you don't need to purchase the OPC UA Server software.  If you want to purchase the OPC UA Server software (and install it on a PC), there are several vendor who have Allen-Bradley drivers... However, FactorTalk Linx Gateway is the recommended OPC UA Server solution because of the tight integration and excellent performance.\n </s>