Programming Model

82596CA LANC Interrupt Control Register

ADR/SIZ

 

 

 

 

$FFF4202A (8 bits)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

15

14

 

13

 

12

 

11

 

10

9

8

 

 

 

 

 

 

 

 

 

 

 

 

 

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

 

Interrupt Request Level. These three bits select the

 

 

 

interrupt level for the 82596CA LANC. 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

 

Interrupt Enable. When this bit is high, the interrupt is

 

 

 

enabled. The interrupt is disabled when this bit is low.

 

INT

 

This status bit reflects the state of the INT pin from the

 

 

 

LANC (qualified by the IEN bit). When this bit is high, a

 

 

 

LANC INT interrupt is being generated at the level

 

 

 

programmed in IL2-IL0 (if nonzero).

 

 

 

E/L*

 

Edge or Level. When this bit is high, the interrupt is edge-

 

 

 

sensitive. The interrupt is level-sensitive when this bit is

 

 

 

low.

 

 

 

 

 

 

 

 

 

PLTY

 

Polarity.

 

 

 

 

 

 

 

 

 

 

 

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

 

 

 

edge/high level of the LANC INT pin.

 

 

When this bit is high, interrupt is activated by a falling edge/low level of the LANC INT pin.

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

3

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Image 233
Motorola MVME1X7P manual 82596CA Lanc Interrupt Control Register, Interrupt level for the 82596CA LANC. Level 0 does not