Epson 4100 manual Serial Interface PIN-OUTS for Printer, Pin # Signal Name Abbr Comment

Operator's Guide B-7

SERIAL INTERFACE PIN-OUTS FOR PRINTER

The printer is a DTE device. The table that follows summarizes the pin assignments on the printer end of a serial interface.

Pin #		Signal Name	Abbr.	Comment
1		Frame Ground	FG
2	%	Transmitted Data	TxD
3	&	Received Data	RxD
4	%	Request To Send	RTS	Always high; + 12v, signal level.
5	&	Clear To Send	CTS	<optional, not implemented>
6	&	Data Set Ready	DSR	<optional, not implemented>
7		Signal Ground	SG
8
9	%	RS-422-A TxD-	TxD 422-	<optional, not implemented>
10	%	RS-422-A TxD+	TxD 422+	<optional, not implemented>
11	%	Auxiliary DTR*	——	Same as Pin 20.
12
13
14
15
16
17		RS-422-A RxD+**
18	&		RxD 422+	<optional, not implemented>
19	%	Auxiliary DTR*	——	Same as Pin 20.
20	%	Data Terminal Ready	DTR	High until buffer fills, then low.
21
22
23
24
25

*Technically, not an RS-232-C signal. See ”DTR Polarity” under Serial Options in the configuration menu. See “Handshaking” later in this appendix for more information.

**RxD on Pin 3 is used as the differential complement RxD 422- of this signal line.