Sharp MZ-5500 Tehnical Manual

Fig.8-2 shows the block diagram of the hard disk interface. Similar to the
MFD, action of the hard disk drive is divided into three major actions of
write, read, and seek. Data transfer with the host is conducted in the l)~lA
mode under the control of the 8237 DMAC. After data are set in the host
interface chip internal register, the data are transferred to the M58725 RAH
in the DMA mode, then the command 1s executed to the hard disk drive
automatically hy the firmware of the interface. This firmware automaticnlly
starts to test (ready, read/write, seek) the hard disk upon power on. If any
error has been encountered during the test, the condition is displnyed on
the video unit by the OS.
Table 8-2 640KB FDD specification
(physical)
(CP/H-86 spec)
Recording capacity
.. 10.7MB
t 10.7MB)
Disks
2
Heads
4
~ecording surfaces
4
Cylinders
317
Tra.cks 317 x 4 tracks (673 x 2 tracks)
Sec tors
17 sectors/track (16 sectors/track)
Track density (TPI)
360
Recording density (BPI)
. ' 9260, maximum
Recording method MFM
Transfer method
MFM
Data transfer speed : 5MB/s
Access time (including settling time):
Average 85ms
Minimum 18ms
Maximum 15ms
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Sharp MZ-5500 Specifications

General

Brand	Sharp
Model	MZ-5500
Category	Desktop
Language	English