1-8
420 Series
1.3
3.5-inch Floppy Disk Drive
The 420 series 3.5-inch removable FDD is a thin, high-performance reliable drive that sup-
ports 720-KB (formatted) 2DD and 1.44-MB (formatted) 2HD disks. When a CD-ROM is
installed in the Selectable Bay, an FDD attachment can be used to connect the FDD to an
external FDD port.
The 420 series FDD is shown in Figure 1-4.
Figure 1-4 3.5-inch FDD
The specifications for the FDD are listed in Table 1-1.
Table 1-1 3.5-inch FDD specifications
Item
2-MB mode
1-MB mode
Storage capacity (KB)
Unformatted
2,000
1,000
Formatted
1,475
737
Number of heads
2
2
Number of cylinders
80
80
Access time (ms)
Track to track
3
3
Average
181
181
Head settling time
15
15
Recording track density (tpi)
135
135
Data transfer rate (Kbps)
500
250
Rotation speed (rpm)
300
300
Recording method
Modified Frequency Modulation (MFM)
