LTA1012 converter can convert the Transfer Data (TD) and Receive Data (RD) of RS-232C serial port to 2 wire half-duplex RS-485 signal. It's the best choice for long distance control devices and point to multi-point bus communications. This interface converter can work without power supply. It can "steal" power from TD signal, RTS signal of RS-485 port or DTR data terminator. It also has a plus function called Automatic Send Data Line Control, this is means that it doesn't need change the hardware configuration or install software. Perfectly surge protection ensures your RS-485 network security. If you need to convert RS232 to RS485 data, then this 9pin by 9pin data converter is what you need, includes a breakout terminal (optional use) and a data sheet with pinout/ connection points 1.Compatibility: EIA/TIA RS232C standard and RS485 standard 2.Interface RS232 side: DB9 female connector. 3.Interface RS485 side: DB9 male connector with optional (included) terminal board. 4.Transmission rate: 300 - 115200bps 5.Transmission distance: RS485 max. 1200m, RS232 side max. 5m 6.Working mode: RS485 half-duplex 7.Working environment: 0 ~ 70 oC, relative humidity 5% - 95% 8.Mechanical dimensions: 88mm x 33mm x 17mm