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Rana Systems Elite Series User Manual

Page 120

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ELITE SERIES USER MANUAL

CP/M ENHANCEMENTS

The final "mount" message comes from the section

of SGLDRIVE which is left in memory as part of

the operating system (CP/M) after the bulk of

SGLDRIVE goes away. This extra little “resi-

dent” section of SGLDRIVE does not consume any

of the user’s memory. It is loaded into that

section of the operating system which is only

required if you have more than one drive. And,

since you don’t have more than one drive (other-

wise you wouldn’t he running SGLDRIVE), this

section of the operating system can he used for

other purposes.

Once this “resident” portion of SGLDRIVE is

loaded, CP/M as an operating system will begin

recognizing two different drives (A: and B:),

even though you only have the one physical drive

attached to your Apple. SGLDRIVE “fools” CP/M

into seeing another drive by constantly watching

which drive CP/M (and standard programs running

under CP/M, such as PIP) is trying to talk to at

any particular time. Whenever CP/M changes from

trying to talk to drive A: to trying to talk to

drive B:, SGLDRIVE displays the message:

Mount B:, Press

This gives you a chance to remove the diskette

which CP/M thinks is the one in drive A:, and

insert the diskette which CP/M thinks is in

drive B:. Once you press:

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