RS-485

As specified in the EIA-485 Standard, Standard for Electrical Characteristics of Generators and Receivers for Use in Balanced Digital Multipoint Systems, RS-485 expands on the RS-422 standard by increasing the number of devices you can use from 10 to 32 and by working with half-duplex bus architectures. Unlike the RS-422 standard, RS-485 addresses the issue of using multiple transmitters on the same line. RS-485 defines the electrical characteristics necessary to ensure adequate signal voltages under maximum load, as well as short-circuit protection. RS-485 can also withstand multiple drivers driving conflicting signals at the same time.