Motorola MVME1X7P Programming the Printer Port, Printer ACK Interrupt Control Register, IL2-IL0

Models: MVME1X7P

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Programming Model

Programming the Printer Port

This section provides addresses and bit level descriptions of the printer port control, status, and data registers.

Printer ACK Interrupt Control Register

ADR/SIZ

 

 

 

 

$FFF42030 (8 bits)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

31

 

30

29

 

28

27

 

26

 

25

 

24

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NAME

PLTY

 

E/L*

INT

 

IEN

ICLR

 

IL2

 

IL1

 

IL0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

OPER

R/W

 

R/W

R

 

R/W

C

 

R/W

 

R/W

 

R/W

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RESET

0 PL

 

0 PL

0 PL

 

0 PL

0 PL

 

0 PL

 

0 PL

 

0 PL

 

 

 

 

 

 

 

 

 

 

 

 

IL2-IL0

These three bits select the interrupt level for the printer

 

 

 

 

ACK. Level 0 does not generate an interrupt.

 

 

 

ICLR

 

In edge-sensitive mode, writing a logic 1 to this bit clears

 

 

 

 

the INT status bit. This bit has no function in level-

 

 

 

 

sensitive mode. This bit is always read as zero.

 

IEN

 

When this bit is high, the interrupt is enabled. The

 

 

 

 

interrupt is disabled when this bit is low.

 

 

 

INT

 

When this bit is high, a printer ACK interrupt is being

 

 

 

 

generated at the level programmed in IL2-IL0 (if

 

 

 

 

nonzero).

 

 

 

 

 

 

 

 

 

E/L*

 

When this bit is high, the interrupt is edge-sensitive. The

 

 

 

 

interrupt is level-sensitive when this bit is low.

 

PLTY

 

When this bit is low, interrupt is activated by a falling

 

 

 

 

edge/low level on the PRACKI* pin.

 

 

 

 

When this bit is high, interrupt is activated by a rising edge/high level on the PRACKI* pin.

Note that if this bit is changed while the E/L* bit is set (or is being set), an ACK interrupt may be generated. This can be avoided by setting the ICLR bit during write cycles that change the E/L* bit.

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Motorola MVME1X7P manual Programming the Printer Port, Printer ACK Interrupt Control Register, IL2-IL0