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.

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