Epson Photo750 manual Serial Interface, Serial interface, Connector pin assignment and signals

EPSON Stylus Photo 750 Revision A

1.3.3		Serial Interface
This section shows specification for serial interface I/F.
				Table 1-11. Serial interface
			Item				Specification
			Standard		Based on RS-423
			Synchronization		Synchronous
			Bit rate		Approx. 1.8Mbps
					•	Start bit	1bit
			Word format		•	Data bit	8bit
					•	Parity bit none
					•	stop bit 1bit
			Handshaking		X-ON/X-OFF, DTR protocol
		Adaptable connector			8-pin mini circular connector
	Recommended interface cable				Apple System Peripheral-8 cable
		Table 1-12. Connector pin assignment and signals
	Pin		Signal	In/Out		Function Description
	No.		Name
	1		SCLK	Out			Synchronous clock
	2		CTS	In			Clear to send
	3		TxD-	Out			Transmitt data-
	4		S.G.	In			Signal ground
	5		RxD-	In			Receive data-
	6		TxD+	Out			Balanced Transmit+
	7		DTR	Out			Data terminal ready
	8		RxD+	In			Balanced Receive+

NOTE: In/Out refers to the direction of signal flow from the printer’s point of view.

Following figure shows port arrangement of serial I/F connector.

8 7 6

5 4 3

2 1

Figure 1-10. Serial I/F Connector Port

Following table shows timing relation of DTR, X-ON/X-OFF handshaking.

Table 1-13. X-ON/X-OFF, DTR protocol

State	Buffer space	X-on/X-off	DTR
Busy	Less than 3072	Send X-OFF code	Off
	bytes
Ready	More than 5120	Send X-ON code	On
	bytes

Product Description Parallel Interface 18