RS-232 to RS-422 conversion is offered in the full featured product
called the Model 256. Differential input/output RS-422 signals are provided
on screw terminals and an RJ-11 connector. The Model 256 provides operation
over 8,000 feet of twisted pair wire into a load of 120 Ohms. Surge
protection is built-in on the RS-422 port. The Model 256 Interface Converter
includes Telebyte's unique DataSpy LCD display, which provides the user
with important status information regarding the operation of the device.
The graphic display presents the user with live status of the transmit
and receive data signals, TD and RD, and control signals, CTS, RTS,
DSR, DCD and DTR. The Model 256 requires only TD, RD, and signal ground
for power and full duplex operation up to 19.2 KBPS. The DTE/DCE switch
allows reversing of pins 2 and 3 of the RS-232 connector to accommodate
computers, terminals and multiplexers.