Visual Display Prompt; The Diskette - LSI M-Three Operator's Manual

2.4 VISUAL DISPLAY PROMPT
At this point, according to which lVI-THREE System is being opera-
ted, either a flashing 'block' (the Cursor), or the message
"Diskette Expected in Selected Drive." with a flashing Cursor at
its right-hand end, will appear in the top left-hand corner of the
Visual Display.* Either way, any keyboard operation will have no
effect on the display.
A 'Diskette' is required.
* I f the screen is blank, adjust the Contrast control at the front of
the Main Control Unit (see Fig. 2/2a, b, c). If the screen is still
blank, or extraneous data is present, switch the system off and wait
at least 15 seconds before repeating the Switch-On procedure. If
either of these conditions persist, switch the system off and call
the manufactu rer for service assistance.
2.5 THE DISKETTE
As previously mentioned, rapid access to large amounts of data
and complex software is essential for a micro-computer to function.
The media which is most suited to this sort of storage and access is
a magnetic disk. There are three types of magnetic disk or diskette
used on the various M-THREE systems; the Mini-Floppy Diskette
(51/4"), the Floppy Diskette (8"), the Winchester Disk.
Both types of diskette have a 'write-protect' facility whereby a
protected diskette can be read from but not written to. On the
5 1/4" diskette this protection is achieved by placing the
appropriate 'sticker' (normally supplied with the diskettes) over
the Write Protect slot (see Fig. 2/3b), however, on the 8" diskette
the sticker must be removed from the slot (see Fig. 2/3a).
Each of the M-TH REE systems needs a Diskette of the appropriate
size (diskettes are not interchangeable) to be placed into its left-
hand Disk Drive in order to bring the system into operation. This
Diskette must have Operating System software on it, making it a
'System Diskette'.
N.B. As the Winchester Disc is a rigid disc and permanently encased
in its drive mechanism, it cannot be loaded and therefore is always
a right-hand Disc Drive.
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