Download Quantum DAT 24 Drive User's Guide

Commands: Request Block Address (02h)
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REQUEST BLOCK ADDRESS (02h)
The REQUEST BLOCK ADDRESS command requests the drive to transfer the
current block address to the Initiator. This command returns the block address
number on tape.
REQUEST BLOCK ADDRESS Command Descriptor Block
The following table shows the layout of the CDB.
Bits
Byte
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
3
0
0
0
0
0
0
0
0
0
Flag
Link
4
Allocation Length
5
vendor unique*
0
0
0
* This vendor-unique field is reserved and must be set to zero.
Command Descriptor Block Field Description
The following table defines the fields in the CDB.
Field
Name
Allocation
Length
Bytes
Bits
4
Description
Set to 0, the default Transfer Length (3) is used. When nonzero, the
number of bytes specified in the Allocation Length (to a maximum of 3
bytes) is transferred.
REQUEST BLOCK ADDRESS Address Data Format
The following table provides the address data format.
Bits
Byte
7
6
5
4
3
2
0
MSB—Block Address
1
Block Address
2
Block Address—LSB
1
0