Tape Format; Tape Partitions; Formatting Partitions - Sony AIT-SDX470 Product Specifications Manual

LED
Off No Tape
On Tape Loaded
Flash Slowly Tape Access in Progress
(Write/Read)
Flash Fast Tape Access in Progress
(Others)
All LED Flash Fast H/w Error Occurred

4.4. Tape Format

The SDX-470V is an implementation of the Advanced Intelligent Tape (AIT-E Turbo, AIT-1 Turbo and AIT-1) format,
a standard developed by Sony for 8mm data storage drives.
- C1,C2, first and second level Error Correction Code, providing correction for random and Burst Symbol errors.
- C3 ECC, third level Error Correction Code, providing correction across frames within groups
- Read-After-Write, where data is verified immediately after it is written and re-written if there is any error.
- Randomizer, to reduce inter-symbol interference.

Tape Partitions

4.4.1.
Tapes can be formatted as a single data space or as two partitions. With two partitions, each has the same structure
and can be written independently. Some for example, the partition further from BOM (Partition 0) can contain data
files, and the partition closer to BOM (Partition 1) could contain a directory of these files, written later.
With the exception of the Device area on the tape, each partition of a 2-partition tape is identical to a single data
space tape in structure. This means each partition has its own Tape Log area; this is necessary because the patterns
of usage may be very different for each partition. Similarly, each has its own Vendor Group, because the partitions
might be written by different drives.
4.4.1.1.

Formatting Partitions

The ATA/ATAPI MODE SELECT command is used to create partitions on a tape. The command can perform the
following operations:
- Set up two partitions on a blank tape.
- Convert a single data space tape to a 2-partition tape.
- Convert a 2-partition tape to a single data space tape.
- Change the size of both partitions on a 2-partition tape.
- Re-size the partitions of a 2-partition.
Note: Formatting is not needed for single partition operation.
The MODE SELECT, Medium Partitions Parameters Page (11h) is used to Format the tape. MODE SELECT, Device
Configuration Page (10h) is used to change from one partition to another, see the MODE SELECT Command
description in the ATA/ATAPI command clause of this manual. The LOCATE Command also has the capability to
select a partition prior to positioning.
Any data on the tape before the format pass becomes inaccessible, even if the format pass is intended only to
change the size of the two partitions. The Tape Logs are also destroyed and new logs created.
If you do not format a new tape, it will be organized as a single data space tape. After data has been written to it,
whether it was first initialized or not, a format pass is necessary to alter its characteristics and hence how it is handled
by the tape drive system.
Note: The format operation can be very time consuming depending on the requested size of the first partition on the
tape. The amount of time required can be approximated by use of the following formula:
- Number of Megabytes in Partition 1 × 0.006 = number of minutes required
- Add 30 additional seconds for processing overhead
SONY AIT-1 Turbo drive SDX-470V series Ver.1.0
Table 4-2: Normal LED indications
Tape Motion Cleaning Request
Cleaning is Not Necessary
Cleaning Request
Cleaning is Not Completed
4. Operation
Replace Tape
No Media Error Occurred
Media Error Occurred
4-5