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Macintosh II Family
Interupt Levels*

 

Below are the interupt levels of the Macintosh models with the MC68030 microprocessor:

Interupt level

MC68030 interuppt lines

Interrupting Source

Automatic vector number

/IPL2

 /IPL2

/IPL2

0

1

1

1

 None  None

1

1

1

0

 VIA1  $19

2

1

0

1

 VIA2, RBV1, OSS2  $1A

3

1

0

0

 None  $1B

4

0

1

1

 SCC  $1C

5

0

1

0

 None  $1D

6

0

0

1

 None  $1E

7

0

0

0

 Interrupt switch3  $1F

1 In the Macintosh IIci, the interrupt functions are handled by the RBV custom IC.
2 In the Macintosh IIfx, the interrupt functions are handled by the OSS custom IC.
3 In the Macintosh IIci and Macntosh IIfx, the parity checkig circuits can also initiate a level-7nterrupt.

* Information gathered from Guide to Macintosh Family Hardware on page 101.