Star Micronics SP298 user manual Appendix D Interface, Pins and Signal Names Serial Interface

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Appendix D: Interface

Pins and Signal Names (Serial Interface)

Pin	Signal	Direction	Function
No.	Name
1	FG	—	Frame ground
2	TXD	OUT	Transmission data
3	RXD	IN	Receive data
			STAR Mode
			When Memory Switch 4-D = 0: Same as DTR signal
4	RTS	OUT	When Memory Switch 4-D = 1: Always SPACE
			ESC/POS Mode
			Same as DTR signal
5	N.C.		Not connected
6	DSR	IN	• DIP Switch 9 = OFF
			STAR Mode
				APPENDIX
			Status of this signal is not checked.
			ESC/POS Mode
			In DTR/DSR communication mode when Memory Switch4-5 = 0, indicates whether data
			receive from host is enabled or disabled.
			Space: Receive enabled
			Mark: Receive disabled
			This signal is not checked in the X-ON/X-OFF communication mode.
			• DIP Switch 9 = ON
			This signal used for external reset. Printer is reset whenever signal is in mark state with
			pulse width of 1mS or more.
7	SG		Signal ground
8 -19	N.C.		Not connected
20	DTR	OUT	Indicates whether data receive from host is enabled or disabled.
			DTR/DSR Communication Mode
			Space when receive is enabled.
			X-On/X-Off Communication Mode
			Always space, except during following conditions:
			• Period between reset and communication enabled
			• During self-test printing and dot alignment adjustment
21 - 24	N.C.		Not connected