Sony SDX-800V/R User Manual

 

SONY AIT-3Ex drive SDX-800V series Ver.1.1 

6-108 

Operation Code (3Bh) 

Obsolete Reserved

Mode 

 

Buffer ID  

 

(MSB) 

Buffer Offset  

 

  

(LSB) 

(MSB) 

Parameter List Length 

 

 

   

(LSB) 

Control 

WRITE BUFFER is used in conjunction with the READ BUFFER command as a diagnostic function. 

WRITE BUFFER command is valid only when there is no tape inserted in the drive, or when the tape is positioned at 

BOT. An attempt to issue the Write Buffer command when the tape is not at BOT will result in a CHECK CONDITION 

status with a Request Sense Key of ILLEGAL REQUEST. 

Note: The drive will write any buffered data to tape prior to executing this command. Any data that is then transferred 

by the WRITE BUFFER is not written to tape. 

Mode: The drive supports the following values within the Mode field. If any other value is set, the drive will terminate 
the command with a CHECK CONDITION status and an ILLEGAL REQUEST sense key set. 

Any Write Data, file-marks or set-marks in buffer will be transfer to tape before this command is executed. 

Mode 

Description 

0000b 
0010b 
1010b 

Write combined header and data 
Write data 
Echo Buffer 

Combined Header and Data Mode - in this mode, the test data to be transferred must be preceded by a four-byte 

header.  The four-byte header consists of all reserved bytes. The Parameters List Length specifies the maximum 

number of bytes that will be transferred during the DATA OUT phase. This number includes four bytes of header, so 
the data length to be stored in the buffer is transfer length minus four. The initiator should ensure that the transfer 

length is not greater than four plus the available length that is returned in the header of the READ BUFFER 

command. 

Data Mode - in this mode, the DATA OUT phase contains only buffer test data. 

Buffer ID: The supported values are: 

0 

80 
81 
82 
83 

Write Group Buffer 
Write Group Buffer 
Write Group Buffer 
Write Group Buffer 
Write Group Buffer 

0                   - 0x01000000 
0                   - 0x01000000 
0x01000000 - 0x02000000 
0x02000000 - 0x03000000 
0x03000000 - 0x04000000 

If an unsupported Buffer ID code is requested, the drive returns a CHECK CONDITION status with an ILLEGAL 

REQUEST sense key. 

Buffer Offset: The buffer offset field contains the byte offset within the specified buffer from which data shall be 

transferred to. The initiator should conform to the offset boundary requirements returned in the WRITE BUFFER 

descriptor. If the target is unable to accept the specified buffer offset, it shall return CHECK CONDITION status, shall 

set the Sense Key to ILLEGAL REQUEST, and set the Additional Sense Code to ILLEGAL FIELD IN CDB.