The bus connection module RER 123 acts as an interface unit between a device with an RS-232 connector and the fibre-optic bus.
Principle of operation
The bus connection module is powered from the host device via the cable. The module converts incoming optical signals to RS-232 signals for the device and vice versa.
Furthermore, the RER 123 has an echo function, which means that it sends the received signals forward and thus enables the connection of devices in a loop configuration. Note that the echo function is always on, so that when only one device is used, every message is echoed back to the sender.