Tandberg Data
Track, Tape format and Encoding Specification
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6-2
Tandberg SLR Reference Manual
6.2. Tape Formats
6.2.1. QIC-5010-DC and SLR6 (SLR24) Formats
User data is transferred from the Host via the SCSI interface into the buffer. All user data is
then organized in logical frames containing 64 blocks of information, see Figure 6.1 for
details.
0
2
4
ÉÉÉ
ÉÉÉ
6 ECC blocks
1
3
5
ÉÉÉ 26 data blocks ÉÉÉ
6 ECC blocks
26 blocks
64 blocks
organized in
two interleaved
frames
144 data tracks
24 servo tracks
Frame withinterleave
Figure 6.1 QIC-5010-DC and SLR6 (SLR24) - organizing of data blocks
The frame contains 52 data blocks and 12 ECC blocks. Both data and ECC are then
interleaved as shown. This means that data blocks 0, 2, 4, 6, ... will generate ECC blocks 0,
2, 4, 6, 8 and 10, while data blocks 1, 3, 5, 7, .... 51 will generate ECC blocks 1, 3, 5, 7, 9 and
11.
Data is written to the tape, two tracks in parallel. This is organized by writing ODD frames on
ODD track numbers while EVEN frames are written on EVEN track numbers. See Figure 6.2.
Frame
Frame
Frame
. . . . . .
11
13
15
Frame
Frame
Frame
. . . . . .
10
12
14
Parallel recording direction
Odd
tracks
Even
tracks
. . . . . .
. . . . . .
Figure 6.2 Parallel recording