Tandberg Data
Track, Tape format and Encoding Specification
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Tandberg SLR Reference Manual
6-15
6.12. Write Data and Filemarks
The positions in which data or Filemarks can be written will be explained in the following
sections. Normally a Write Data or Write Filemark command can not be performed in other
positions than those described.
The Drive will have to position correctly and write at least one block after having performed
either a Write Data or a Write Filemark command. Datablocks and Filemarks are equal in
size. According to this - both Write Data and Write Filemark commands are treated equally.
6.12.1. Write From Beginning of Tape
If the tape is positioned at Beginning Of Tape, and receives a Write command, the following
functions will be performed internally in the Drive:
•
First the Drive will assure that a cartridge is inserted. The cartridge can not be write-
protected, and must be of a quality that can be written on the actual drive.
•
The drive will use the servo- or the reference tracks to position the head to track 0.
•
The number of datablocks according to the Write command is written when the data is
received into the drives internal data buffer.
•
The Drive may continue to write data on the following tracks.
•
All track changes are transparent to the Host.
6.12.2. Write From a Position on the Tape
When Write Data or Filemark commands are continuously given from Beginning Of Tape, the
Drive will write data and Filemarks continuously. No extra handling is necessary.
If the cartridge is not written continuously from Beginning Of Tape, but data is to be appended
to an already written tape, the following must be performed:
•
The Host must position the tape at EOD (End Of Data) before the Write function can
be executed.
•
Positioning the tape at EOD means that the Drive has read past all the datablocks
and Filemarks in front of the EOD, and also read past this position, resulting in the
CHECK CONDITION with BLANK CHECK in the Sense Key.