Intermec PX4i Double Serial Interface Kit Installation Instructions - Page 31

4 Serial Interface "uart3:", "uart4:", and "uart5:" This chapter describes how to modify the interface board for RS-232 non-isolated (standard), RS-422 non-isolated/full duplex, or 20 mA current loop on the "uart3:", "uart4:", and "uart5:" port and explains the configuration of the interface connector. The connector is marked "UART B" on the interface board. When fitting driver circuit and straps before installing the interface board, make sure that the circuit is not fitted upside down (see front end markings in the illustrations). Also make sure that the "legs" of the circuit fit into the slots in the socket and are not bent. Take ample precautions to protect the board and circuits from electrostatic discharges. Double Serial Interface Kit Installation Instructions 27