Epson EPL-7000 chassis, (RD+), (SD+), (SD-), (RD-), Description, SelecType, by the printer, HIGH with SelecType, Clear. This pin indicates that the, RS-422, level is RS-422

Interface Specifications

SignalPin	RS-232C	RS-422	Direction	Description
1	FG		—	This line is connected to the printer
				chassis.
2	TXD		OUT	Transmits data. This pin transmits serial
				data from the printer to the computer.
3	RXD	(RD+)	IN	Received data. This pin transmits serial
			(IN)	data from the computer to the printer.
4	RTS		OUT	Request to send. This pin is held HIGH
				by the printer.
5	CTS		IN	Clear. This pin indicates that the
				computer is ready to receive data from
				the printer. The printer will not proceed
				unless the signal is HIGH. Can be set
				HIGH with SelecType.
6	DSR		IN	Data set ready. This pin indicates that the
				computer is ready to receive data from
				the printer. Can be set HIGH with
				SelecType.
7	SG		—	Signal ground. This pin provides a
				ground for all the signal lines.
8	DCD		IN	Data carrier detect. Always ignored.
9		(SD+)	(OUT)	Send data. This pin sends serial data
				from the printer to the computer. Signal
				level is RS-422.
10		(SD-)	(OUT)	Send data. This pin sends serial data
				from the printer to the computer. Signal
				level is RS-422.
18		(RD-)	(IN)	Receive data. This pin transmits serial
				data from the computer to the printer.
				Signal level is RS-422.

8-14Technical Specifications