Ampro Corporation 5001451A manual Parallel Port Register Bits

Table 2-22. Parallel Port Register Bits

		Signal Name		Active	J5	DB25F
Register	Bit	or Function	In/Out	High/Low	Pin	Pin
DATA	0	PD 0	I/O	High	6	2
(378h)	1	PD 1	I/O	High	10	3
	2	PD 2	I/O	High	14	4
	3	PD 3	I/O	High	18	5
	4	PD 4	I/O	High	22	6
	5	PD 5	I/O	High	26	7
	6	PD 6	I/O	High	30	8
	7	PD 7	I/O	High	34	9
STATUS	0	TMOUT	In	---	---	---
(379h)	1	0	---	---	---	---
	2	0	---	---	---	---
	3	ERROR*	In	Low	8	15
	4	SLCT	In	High	50	13
	5	PE	In	High	46	12
	6	ACK* (IRQ)	In	Low	38	10
	7	BUSY	In	High	42	11
CONTROL	0	STB*	Out*	Low	2	1
(37Ah)	1	AUTOFD*	Out*	Low	4	14
	2	INIT*	Out*	High	12	16
	3	SELIN*	Out*	High	16	17
	4	IRQE	---	High	---	---
	5	PCD	---	High	---	---
	6	1	---	---	---	---
	7	1	---	---	---	---

Note: * Can also be used as input (see text).

Table 2-23. Standard and PS/2 Mode Register Bit Definitions

Signal	Full Name	Description
Name
TMOUT	Time-out	Valid only in EPP mode , this signal goes true after a 10 ∝ S time-
		out has occurred on the EPP bus. This bit is cleared by reset.
ERR*	Error	Reflects the status of the -ERROR input. 0 means an error has
		occurred.
SLCT	Printer selected	Reflects the status of the SLCT input. 1 means a printer is on-line.
	status
PE	Paper end	Reflects the status of the PE input. 1 indicates paper end.
ACK*	Acknowledge	Reflects the status of the ACK input. 0 indicates a printer received
		a character..
BUSY*	Busy	Reflects the complement of the BUSY input. 0 indicates a printer
		is busy.
STB*	Strobe	This bit is inverted and output to the -STROBE pin.
AUTOFD	Auto feed	This bit is inverted and output to the -AUTOFD pin.
INIT*	Initiate output	This bit is output to the -INIT pin.

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