... ). 1, RXD LED: When PC(personal computer) receives data, this light will flash.2, TXD LED: When PC ... sends out data, this light will flash.3, POWER LED: When ... module to the USB interface on PC by the data line from smartgen.5, LINK interface: This ... This is a generic isolation RS485 communication interface.7, RS232-C: This is a generic DB9 serial communication interface. sg72 ...