SCSI Commands
Page
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SEND DIAGNOSTIC
The Send Diagnostic command requests the drive to perform diagnostic operations
on itself. The diagnostic tests are part of the drive’s resident firmware.
The Receive Diagnostic Results command may be used to retrieve the result of the
diagnostic operations.
A Self Test bit of one requests the drive to perform its self test diagnostic.
Command Descriptor Block
Byte
Bits
7
6
5
4
3
2
1
0
0
Operation Code (1Dh)
1
Self-Test Code
PF
Reserved Selftest
Devoffl
UnitOffl
2
Reserved
3
Parameter List Length (MSB)
4
Parameter List Length (LSB)
5
Control
Field Descriptions
Field
Bytes
Bits
Description
Operation
code
0
The Operation Code for Send Diagnostic is 1Dh.
Self-test code
1
5-7
This bit field is not supported and must be set to 0.
Pf
1
4
This bit is not supported and must be set to 0.
Selftest
1
2
1 = Perform self test diagnostic.
Devoffl
1
1
This bit is not supported and must be set to 0.
UnitOffl
1
0
This bit is not supported and must be set to 0.
Parameter list
length
3-4
This field is not supported and must be to 0.
Reserved
All reserved bits must be 0.
Control
5
The control field must be 0.
Completion Status
Code
Message
Description
00h
Good
Status
•
The drive is ready to perform any appropriate command.
•
The drive remains in any previously set mode.
•
The tape position is not changed.
02h
Check
Condition
Use the Request Sense command to retrieve status information. Possible
Sense Keys are:
Code
Message Description
02h
Not Ready
No cartridge is inserted in the drive.
04h
Hardware Error
Drive hardware failure detected.
05h
Illegal Request
The CDB contains an invalid bit.
06h
Unit Attention
The cartridge was changed, or the drive was
reset prior to this command.