ATC-101 port powered RS-232 to RS-422 interface converter. The model ATC-101 is a non-power RS-232 to RS-422 interface converter. The model TBATC-101 has a DB9 female connector for the RS-232 interface and a 6 screw terminals connector or DB9 male connector for the RS-422 differential input and output interface. Model TBATC-101 can convert the TD and RD signals of RS-232 into balanced full-duplex RS-422 signals.