RS-499
RS499 is an EIA standard for interfaces between Data Communication Equipment( DCE) and Data Terminal Equipment( DTE).
The RS499 interface standard offers high transmission speeds with data rates of up to 2 Mbit/s as well as longer cable lengths and more functions than the RS232. RS499 is designed for binary, serial, synchronous and asynchronous communication systems alike. Half- duplex operation is supported as well as duplex operation. Transmission can be via two- or four-core cables.