Oriole electronics offers dataforth ldm 2485, a high speed rs-232 to rs-485 converter which can convert a pc into an rs-485 workstation. This model does not require power supply for operation. Use of low power circuits and sensitive optical receiver allows the device to derive all necessary power from the rs-232 data and the control signals.It can address up to 50 devices in a miilti-point polling environment by operating over 2 to 4 wires, at data rates up to 115.2 kbps. These products have 5 different configuration parameters [carrier control, rts/cts delay, receive impedance, transmit-off impedance and echo] that allow to finetune the converters to a particular application. The host device is protected from electrical transients due to lightening strikes or operation of heavy industrial equipment.