The RS232 to RS485/422 converters adapt standard Com ports of a PC to the electrical specifications of RS485 or RS422 networks. Applications on the PC get simple access to the devices connected to such networks. RS422 and RS485 are designed to support very long transmission lines, high data rates of up to 1 MBit/s, as well as multiple devices connected at the same time. These features are superior to RS232. These functions also allow to transmit RS232 signals through a pair of these converters. This allows to extend the limited communication range of RS232 up to the limits of RS422. At the same time the converters can isolate the RS232 link.