Sony SDX-700C, Product Specifications Manual

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6.Command Specification VERIFY
SONY AIT-3 drive SDX-700 series Ver.2.1 6-106
6.28.
VERIFY 13h
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (13h)
1 Logical Unit Number Reserved Immed(0)
BytCmp
(0)
Fixed
2 (MSB)
3 Verification Length
4 (LSB)
5 Unused (00b) Reserved Flag Link
VERIFY verifies one or more blocks beginning with the next block on the tape. The verification is a media verification
only. No data is transferred between the Host and the Drive.
Fixed : This bit specifies both the meaning of the Verification Length field and whether fixed-length or variable-length
blocks are to be verified.
If the Fixed bit is set to ZERO, Variable Block mode is requested. A single block is verified with the Verification
Length specifying the maximum number of bytes that are to be verified.
If the Fixed bit is set to one, the Verification Length specifies the number of blocks to be verified by the drive. This is
valid only if the logical unit is currently operating in Fixed Block mode, in other words, when it has been instructed to
use fixed-length blocks with MODE SELECT. The current block length is the block length defined in the MODE
SELECT command. If the Fixed bit is set and the drive is in Variable Block mode, the VERIFY is rejected with a
CHECK CONDITION status and an ILLEGAL REQUEST sense key set. The VERIFY is also rejected if the drive is in
Fixed Block mode and the Fixed bit is not set with a CHECK CONDITION status and an ILLEGAL REQUEST sense
key set.
BytCmp : This function is not supported. If this bit is set, the command is rejected with CHECK CONDITION status
with the ILLEGAL REQUEST sense key set.
Immed : This function is not supported. If this bit is set, the command is rejected with a CHECK CONDITION status
with the ILLEGAL REQUEST sense key set.
VERIFY terminates when the Verification Length has been satisfied, when a File mark, a Save-Set Mark (if the drive
has been configured to report Set-marks), EOD or the physical EOM is encountered. The status and sense data for
each of these conditions are handled in the same manner as in READ. Upon completion of VERIFY, the logical
position is located after the last block from which data was verified or after the File mark, or Set-mark, if one is
encountered. When the Verification Length is ZERO, no data is verified and the current logical position is not be
changed.
If the actual block length is different from the Verification Length, a CHECK CONDITION status is returned. Within
the Sense data, the Incorrect Length Indicator (ILI) bit and Valid bit will be set to one, the Sense Key field is set to NO
SENSE and the Information Bytes are set to the difference (residue) between the requested Verification length and
the actual block length, or in Blocked Mode, the difference (residue) between the requested number of blocks and
the actual number of blocks verified.
If the drive encounters a File mark, the drive will return a CHECK CONDITION status. Within the Sense data, the File
mark and Valid bits are set and the Sense Key field is set to NO SENSE. The Information fields contain the residue
count. The Additional Sense Code and Additional Sense Code Qualifier fields are set to File mark Detected. Upon
termination, the media will be logically positioned after the File mark (EOM side).
If, however, the drive encounters a Set-mark during VERIFY, nothing is reported unless the drive has been
configured through MODE SELECT to Report Set-marks. The drive will space over the Set-mark and continue the
VERIFY. If the Report Set-marks configuration is enabled then the File-mark and Valid bits are set and the Sense
Key field is set to NO SENSE. The Information fields contain the residue count and the Additional Sense Code and
Additional Sense Code Qualifier fields are set to Set-mark Detected. The tape is logically positioned after the
Set-mark (EOM side).