Quantum Audio STT2401A Manuel D’Utilisation

Page de 137
ATAPI Interface 
Chapter 5 
Seagate Travan 40 Product Manual 
Page 85 
 
 
VERIFY (Group 0, Op. Code 13) 
The VERIFY command performs a Verification Check on a specified number of data 
blocks on the tape without involving the Host. Verification starts at the present 
position of the tape and continues for the specified number of blocks. If a data block 
cannot be verified by CRC recovery then ECC and read retries will be employed in 
an attempt to recover the data. The command terminates as a result of one of the 
following conditions: 
• 
The specified number of blocks has been verified. 
• 
A Filemark or Setmark has been detected. 
• 
The End-of-Data has been reached. 
• 
A Verification failure occurred. 
Upon termination, the tape is positioned to read the block following the last data 
block or Filemark read correctly. 
CDB for VERIFY command 
 
Data Bits 
 
Byte 
Hex 
13 
IMM 
BytCmp
 
FBM 
0X 


MSB 
Length Of Verification 
LSB 
XX 
XX 
XX 
00 
IMM: When the IMMEDIATE bit is set to 0, status will be returned to the Host when 
the VERIFY operation is completed. When set to 1, the status will be returned to the 
Host as soon as the VERIFY operation is initiated. 
NOTE:  The ATAPI interface does not have an IMM bit or functional equivalent. The 
DSC and BUSY bits in the Host taskfile status register indicate bus and 
command status. 
BytCmp: When the Byte Compare bit is set to 0, the drive will perform a media data 
recoverability verification only. A Byte Compare bit set to 1 indicates the drive will 
perform a byte-by-byte compare between data read from the media and data sent 
from the Host. BytCmp=1 is not supported. 
FBM: The Fixed Block Mode bit (FMB) set to 1 indicates fixed block mode operation.