Recording Method; Lto-1 Drive; Lto-2 Drive - Certance LTO 1 User Manual

Theory

LTO-1 Drive

With the LTO-1 drive, there are 384 data tracks on the LTO tape, numbered 0 through 383. Data
track 383 is the track closest to the bottom edge of the tape (the reference edge). The area between
adjacent servo bands is a data band. There are 4 data bands, each of which includes 96 data
tracks. The data bands are numbered 2,0,1,3. Data band 2 is closest to the bottom edge of the
tape.
A track group is a set of tracks that is recorded concurrently. The sets of 12 data tracks in a data
band are data sub bands. There are 8 data sub bands per data band. The data tracks are accessed
in a serpentine manner.
A wrap is a track group recorded in the physical forward or physical reverse direction. The wraps
are recorded in a serpentine fashion starting in data band 0. The tape contains 48 track groups, 24
written in the forward direction and 24 written in the reverse direction. Even-numbered wraps are
recorded in the forward direction (BOT to EOT), and odd-numbered wraps are recorded in the
reverse direction (EOT to BOT).

LTO-2 Drive

With the LTO-2 drive, there are 512 data tracks on the LTO tape, numbered 0 through 511. Data
track 511 is the track closest to the bottom edge of the tape (the reference edge). The area between
adjacent servo bands is a data band. There are 4 data bands, each of which includes 128 data
tracks. The data bands are numbered 2,0,1,3. Data band 2 is closest to the bottom edge of the
tape.
A track group is a set of tracks that is recorded concurrently. The sets of 16 data tracks in a data
band are data sub bands. There are 8 data sub bands per data band. The data tracks are accessed
in a serpentine manner.
A wrap is a track group recorded in the physical forward or physical reverse direction. The wraps
are recorded in a serpentine fashion starting in data band 0. The tape contains 64 track groups, 32
written in the forward direction and 32 written in the reverse direction. Even-numbered wraps are
recorded in the forward direction (BOT to EOT), and odd-numbered wraps are recorded in the
reverse direction (EOT to BOT).

Recording Method

The LTO-1 and LTO-2 drives record data using write-equalized (1,7) Run Length Limited (RLL) code.
RLL (1,7) Data bits are defined as follows:
A ONE is represented by a flux transition at the center of a bit-cell.
•
A ZERO is represented by no flux transition in the bit-cell.
•
Recording Method
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