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DUMP COMMAND
11. 4 --
Examples
50
60
70
G
=
54
81
46
49 4C
45 OD
30
46
81
31 33 81 49 4E 56
T.FILE.OF. 13. INV
41
4C 49 44
81
4C
4F
41
44
81
41 44 44
52 45
53
ALID. LOAD. ADORES
53
OD 31
33 81 31 34
81
49 4E 56 41
4C
49 44 81
S. 13. 14. INVALID.
The following example
illust~ates
how the
DUMP
command
car.
be used to ::1=ix:: part
o-r
the MDOS system
tables
that
wEI-a
round to be in e,..,..or
by
the
REPAIR
command (Chapter
22>'
No
discussion
is
given
neT"e
Or
the REPAIR command;
however,
the
example does show what the REPAIR command
displayed
insofar
as diagnostic messages are concerned.
These messages contain
the required information needed by the operator so
that
the
DUMP command can be used to "rix" the
bad
sector.
The REPAIR
command could show the following on the system console:
=REPAIR
DISK ID:
MDOS0300
VERSION:
03
REVISION: 00
DATE:
072578
USER:
SYS
DEVELOPMENT DRVO
06
03 01
TESTPROG.SA
05BC
05810000
ILLEGAL ATTRIBUTE OR UNUSED BYTES.
DELETE? N
33 GOOD FILES
00 FILES WITH BAD RIBS
RECONSTRUCTED C. A. T. MATCHES DISK .
=
The first
-Few
lines show the contents
Or
the ID sector.
The
line
that
begins
with
"06
03 01
11
shows the contents of a
directory entry that has been found in
er~or.
The subsequent
line
shows
the error that
REPAIR
detected.
The error is in
the attribute bytes
of
the
directory
entry.
Chapter
22
describes
the format of the displayed directory entry.
With
that information,
the operator knows that the attribute rield
is
displayed
as
"0581".
The
error
is
in
the
least
significant byte
Or
this field.
It should be zero, not
lI8i"
as
shown.
From
the other information displayed,
it can be
seen that this directory entry is the second
entry
(01)
in
the
third
sector
(03)
of
the
directory.
With
that
inrormation the DUMP command
is
used
~o
read
the
sector
containing
the
bad
directory
entry into the sector change
buffer.·
The buffer is modified so that the
"81"
becomes
a
1100".
In the following example,
the sector change buffer is
displayed both before
and
aPter the modification,
Such repair functions must
be
performed
with
extreme
caution.
The REPAIR command should always be run again after
a system sector has been changed in this way to
ensure
that
the change was made correctly.
Page
11-14
-
------
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/
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