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Important: This document is part of the Legacy section of the ADC Reference Library. This information should not be used for new development.

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Macintosh Plus Pinouts


This note gives pinout descriptions for some of the Macintosh Plus ports and Macintosh Plus cables that are different than the Macintosh 128K and 512K.

[Jan 01 1986]


Below are pinout descriptions for some Macintosh Plus ports and cables that are different than the Macintosh 128K and 512K. Note that any unconnected pins are omitted.

Macintosh Plus Port Pinouts

Macintosh Plus Serial Connectors

Figure 1: Macintosh Plus Serial Connectors (Mini DIN-8)

Macintosh Plus SCSI Connector

Figure 2: Macintosh Plus SCSI Connector (DB-25)

Pin Name Description/Notes

1 REQ-

2 MSG-

3 I/O-

4 RST-

5 ACK-

6 BSY-

7 Ground

8 DB0-

9 Ground

10 DB3-

11 DB5-

12 DB6-

13 DB7-

14 Ground

15 C/D-

16 Ground

17 ATN-

18 Ground

19 SEL-

20 DBP-

21 DB1-

22 DB2-

23 DB4-

24 Ground

25 TPWR Not connected

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Macintosh Plus Cable Pinouts

Apple System Peripheral-8 Cable

Figure 3: Apple System Peripheral-8 Cable

(connects Macintosh Plus to ImageWriter II and Apple Personal Modem )

(Product part number: M0187)

(Cable assembly part number: 590-0340-A (stamped on cable itself).

( DIN-8 ) ( DIN-8 )

1 2

2 1

3 5

4 4

5 3

6 8

7 7

8 6

Macintosh Plus Adapter Cable
(connects Macintosh Plus DIN-8 to existing Macintosh DB-9 cables)

(Apple part number: M0189)

(Cable assembly part number: 590-0341-A (stamped on cable itself).

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Macintosh Hardware Reference Manual

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Acrobat version of this Note (156K)


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