B.3 Serial Interface (Option)
B-6
B.3 Serial Interface (Option)Installing the optional serial interface board kit (IB-11) in the printer enables connection to a
computer with an RS-232C standard serial interface.
B.3.1 Interface Signals
Tabl e B-4 below shows the p ins and corresponding input and output signals of the RS-232C
interface connector.
B.3.2 Interface voltage levels
The voltage levels of the interface signals conform to EIA RS-232C specifications. The
voltage level of SPACE is 3 to 15 volts. The voltage level of MARK is -3 to -15 volts.
Voltages between -3 and 3 volts are undefined.
Pin In or out Signal Description
1— FG Frame Ground. This pin is connected directly to the printer
frame.
2Out TXD Transmit Data. This pin is used to output asynchronous data
sent from the printer to the computer. This signal is often used
in handshaking.
3In RXD Receive Data. This pin is used to input serial asynchronous
data sent from the computer to the printer.
4Out RTS Request To Send. This output is always high (above 3 volts).
5In CTS Clear To Send. Not used.
6In DSR Data Set Ready. Not used.
7— SG Signal Ground. This pin is used to establish a common refer-
ence level for the voltages of all signals other than Frame
Ground.
20 Out DTR Data Terminal Ready . This pin is used to notify the status of
the printer buffer (i.e., nearly full or nearly empty) when hand-
shaking is used. The pin goes high (above 3 volts) when the
buffer is able to accept more data.
Table B-4