User guide
Summary of Commands:
An image header (which includes the source and length infor-
mation as well
as
the level
of
redundancy) is stored at the begin-
ning
of
the
stored data. Each image can be assigned a
number
from 1
to
255, while 0
is
reserved for
directory
usage.
Image headers can be read by using the IDENTIFY command. A
check for the
proper
file
ID
can be made
or
the next file header
encountered can be read.
The
following is a list
of
the commands used by the Mirror:
BACKUp, IDENTIFY, RESTORE, RESTORE
RETRY,
VERIFY,
VERIFY
RETRY, and REPORT ERRORS
Error Explanation:
Three
of
the most common errors that you may encounter dur-
ing the use
of
the
Mirror
deal with tape timeout.
If you
do
not correctly position the cassette when you
start
the
tape, the
IMAGE NOT FOUND error displays. The control program
searches
for
the start
of
an
image for about one minute. If no
image is
found
within that time,
it
gives
up
the search.
If a restore is being done and the size
of
the image on the tape
does
not
match the size
of
the area being restored, the IMAGE
SIZE MISMATCH displays. The IDENTIFY option can be used
to
determine the size (in blocks)
of
the video image.
Another error indicates that the tape you are trying
to
read has
been
partially erased. This can occur
if
you are recording more
than one image on a video cassette and you
fail
to
properly posi-
tion the tape
prior
to
recording. This error is called tape
timeout
during playback operation.
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