IBM Ultrastar 36LZX, Specifications

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8.16 READ BUFFER (3C)
LINK FLAG Reserved = 0 VU = 0 9
(MSB)
Allocation Length
(LSB)
6
7
8
(MSB)
Buffer Offset
(LSB)
3
4
5
Buffer ID = 0 2
Mode Reserved = 0 1
Command Code = 3Ch 0
0 1 2 3 4 5 6 7
Bit
Byte
Figure 111. READ BUFFER (3C)
The READ BUFFER command is used in conjunction with the WRITE BUFFER command as a diag-
nostic function for testing the memory of the drive and the SCSI bus integrity. This command does not
alter the medium.
The function of this command and the meaning of fields within the command descriptor block depend
on the contents of the mode field.
MODE Description
0000 Read Combined Header and Data
0010 Data
0011 Descriptor
1010 Read Data from Echo Buffer
1011 Echo Buffer Descriptor
All others Not supported.
Ultrastar 36LZX hard disk drive specifications
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