Hardware pinouts information and cables schemes

Apple Macintosh External Floppy disk drive pinout

connector or cable wiring scheme

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This connector is present on the Macintosh Duo MiniDock and PowerBook Duo Floppy adapter. An HDI-20 1.4 MB drive can be connected to this port.

20 pin Apple HDI-20 connector layout

20 pin Apple HDI-20 connector
at the Apple computer, looking into cable-side connector



Pin Name Description
1GNDSignal Ground
2GNDSignal Ground
3GNDSignal Ground
4GNDSignal Ground
5NCNo connection
6+5V+5 volts DC
7+5V+5 volts DC
8+5V+5 volts DC
9+5V+5 volts DC
10NCNo connection
11PH0Phase 0: state control line
12PH1Phase 1: state control line
13PH2Phase 2: state control line
14PH3Phase 3: register write strobe
15WREQWrite request
16HDSELHead select
17ENBL2External drive select
18RDRead data
19WRWrite data
20NCNo connection


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Pinouts.ru > Disk drives connectors pinouts listing >  Pinout of Apple Macintosh External Floppy disk drive and layout of 20 pin Apple HDI-20 connector
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Source(s) of this and additional information: Apple "Ports and Pinouts", from Hardware Book 0 reports
Last updated at Sat Jun 25 2005. Submit additions or corrections for this document. Is this document correct or incorrect? What is your opinion?
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