Epson LQ-800 The Parallel and Serial Interfaces, F-1, Parallel Interface, Table F-1.Pins and signals

Appendix F

The Parallel and Serial Interfaces

The LQ-800/1000 printers have both parallel and serial interfaces to communicate with the computer; this appendix describes these inter- faces.

Parallel Interface

Connector pin assignments and a description of respective interface signals are shown in Table F-1.

Table F-1. Pins and signals

Signal	Return		Direc-		Description
Pin	Pin	Signal	tion
1	19		IN		pulse to read data in Pulse
		STROBE		STROBE
				width must be more than 0.5
				microseconds at the receiving terminal.
2	20	DATA 1	IN	These signals represent information
3	21	DATA 2	IN	of the 1st to 8th bits of parallel
4	2 2	DATA 3		data, respectively Each signal is
5	23	DATA 4	IN	at HIGH level when data is logical
6	24	DATA 5	IN	1 and LOW when it is logical 0.

725 DATA 6

8	26	DATA	7	IN
9	2 7	DATA	8	IN

1028 ACKNLG OUT Approximately 12-microsecond pulse. LOW indicates that data has been received and that the printer is ready to accept more data.

11	29	BUSY	OUT	A HIGH signal indicates that the printer
				cannot receive data. The signal goes
				HIGH in the following cases:
				1) During data entry (ea.char.time)
				2)	During printing
				3)	When Off-Line
				4)	During printer-error state

F-1