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This note gives pinouts for Macintosh ports, cables, and other products.

[Oct 01 1989]


Below are pinout descriptions for the Macintosh ports, cables, and various other products. Please refer to the Hardware chapter of Inside Macintosh and the Macintosh Hardware Reference Manual for more information, especially about power limits. Note that unconnected pins are omitted.

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Macintosh Port Pinouts

Macintosh Serial Connectors (DB-9)
Pin        Name            Description/Notes
1        Ground
2        +5V             See Inside Macintosh  for power limits
3        Ground
4        TxD+            Transmit Data line
5        TxD<            Transmit Data line
6        +12V            See Macintosh Hardware chapter for power limits
7        HSK             HandShaKe: CTS or TRxC, depends on Zilog 8530
8        RxD+            Receive Data line; ground this line to emulate RS232
9        RxD<            Receive Data line

Macintosh Mouse Connector (DB-9)

Other Pinouts

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Macintosh Cable Pinouts

Note for the cable descriptions below:

The arrows ("Æ") show which side is an input and which is an output. For example, the notation "a Æ b" means that signal "a" is an output and "b" is an input.

When pins are said to be connected on a side in the Notes column, it means the pins are connected on that side of the connector.

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Macintosh to Non-Apple Product Cable Pinouts

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Macintosh Hardware Reference Manual

Technical Note M.HW. MacPlusPinouts -- Macintosh Plus Pinouts

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Acrobat version of this Note (376K)


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