Write Buffer 3Bh - Sony AIT-SDX560 Product Specifications Manual

7. ATAPI Packet Command Specification

7.25. WRITE BUFFER 3Bh

Bit 7
Byte
0
1
2
3 (MSB)
4
5
6 (MSB)
7
8
9
10
11
WRITE BUFFER is used in conjunction with the READ BUFFER command as a diagnostic function for testing the
buffer and bus integrity of the drive. A REWIND command should be sent to the drive after WRITE/READ
BUFFER diagnostic testing to allow normal operation.
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. This command is provided for
downloading firmware.
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.
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 TRANSFER. This number includes four bytes
of header, so the data length to be stored in the buffer is transfer length minus four. The host 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 TRANSFER contains buffer data only.
Buffer ID: The supported values are:
If an unsupported Buffer ID code is requested, the drive returns a CHECK CONDITION status with an ILLEGAL
REQUEST sense key.
7-70
6 5 4
Operation Code (3Bh)
Reserved
Parameter List Length
Table 7-59: Write Buffer Mode Field
Mode
000b Write Combined Header and Data
010b
Buffer ID
0
1
3 2
Buffer ID
Buffer Offset
Reserved
Reserved
Reserved
Description
Write Data
Description
Write Interface Buffer
Write Group Buffer
SONY AIT-2 Turbo drive SDX-560V series Ver.1.0
WRITE BUFFER
1 0
Mode
(LSB)
(LSB)