User guide

The Virtual Drive Offsets
TASK ?
ALL CP/M BASED SYSTEMS CAN ADDRESS
THE DRIVE AS ONE UNIT. THUS THE
VDO TABLE SHOULD BE SET WITH AN
OFFSET OF 0 FOR THE VIRTUAL DRIVE 1
---
VIRTUAL DRIVE/TRACK ---
OFFSET TABLE
DRIVE TRACK
1
o
VIRTUAL DRIVE 1 : 0
VIRTUAL DRIVE 2 :-
v
Checking the virtual drive/track offset table (20 MB drives only)
You should still be in the diagnostic program. Select the DRIVE
PARAMETERS option. J
After entering the drive #, you will set a display of the drive
parameters. The
virtual offset table is the last table displayed. For
a 20 MB drive, this
usually has the form:
This number (or numbers)
allows the user to make the drive
appear
to be subdivided into a number (less than 8) of subdrives
that appear to the software as daisy chained drives. (This scheme
is
mainly used on Corvus' Apple products.) In the example above,
we
could still address the whole drive as Corvus drive #1, but the
controller would also respond as Corvus drive #2 and address the
last half of the disk space.
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