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D.47 poll (master and slave) – Intel 386 User Manual

Page 614

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D-49

SYSTEM REGISTER QUICK REFERENCE

D.47 POLL (MASTER AND SLAVE)

Poll Status Byte
POLL (master and slave)
(read only)

Expanded Addr:
ISA Addr:
Reset State:

master

slave

F020H

F0A0H

0020H

00A0H

XXH

XXH

7

0

INT

L2

L1

L0

Bit

Number

Bit

Mnemonic

Function

7

INT

Interrupt Pending:

0 = No request pending.
1 = Indicates that a device attached to the 82C59A requires servicing.

6–3

Reserved. These bits are undefined.

2–0

L2:0

Interrupt Request Level:

When bit 7 is set, these bits indicate the highest-priority IR signal that
requires servicing. When bit 7 is clear, i.e., no request is pending, these
bits are indeterminate.