Lexmark Printer manual Rts, Cts, Dsr, Dtr

8-27

Interfaces

Table 8-4: Dedicated Serial Connector Pin Assignments (RS-232C) (Continued)

Pin	Signal	Direction	Description
4	RTS	Out	Request to Send. The printer sets this signal high and the
			signal remains high while the printer is on.
5	CTS	In	Clear to Send. This pin is optionally used for serial data flow
			control protocol when in serial mode.
6	DSR	In	Data Set Ready. This pin is optionally used for data
			validation, depending on the Honor DSR setting, or flow
			control, depending on the Serial Protocol setting.
7	GND		Logic Ground
20	DTR	Out	Data Terminal Ready. This pin is optionally used for serial
			data flow control protocol when in serial mode.