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.