Specifications

CHAPTER 3
I/O Features
24 Disk Drives
Disk Drives 3
The Macintosh Performa 6400 computer has one internal high-density floppy disk drive,
one internal ATA (IDE) hard disk drive, and an internal SCSI CD-ROM drive.
Floppy Disk Drive 3
The Macintosh Performa 6400 computer has one internal high-density floppy disk drive
(Apple SuperDrive). The drive is connected to a 20-pin connector on a cable that is
connected to the main logic board by the internal chassis connector. Table 3-3 shows the
pin assignments on the floppy disk connector.
Table 3-3 Pin assignments on the floppy disk connector
Pin number
Signal
name Signal description
1 GND Ground
2 PH0 Phase 0: state control line
3 GND Ground
4 PH1 Phase 1: state control line
5 GND Ground
6 PH2 Phase 2: state control line
7 GND Ground
8 PH3 Phase 3: register write strobe
9 +5V +5 volts
10 /WRREQ Write data request
11 +5V +5 volts
12 SEL Head select
13 +12V +12 volts
14 /ENBL Drive enable
15 +12V +12 volts
16 RD Read data
continued