... port of computer ), no outside power needed. Small size, long transmission distance, high rate, stable performance. It applys DB9 common ... RS-422 standardRS-232 signalTX, RX, GNDRS-422 signalD+, D-, GNDWorking formatAsynchronism, point to point or multi point,4 wire ... RS-422 side DB-9 male or 4 terminal blockEnvironment Working temperature-20 to 60Storage temperature-25 to 85HumidityRelative humidity 5 ...