Quantum LTO 4, User Manual

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SCSI Commands: 53BWRITE BUFFER Page 221
3.41 WRITE BUFFER
The WRITE BUFFER command is used in conjunction with the READ BUFFER
command as a diagnostic function for testing the data buffer memory of the drive
and confirming the SCSI bus or Fibre Channel interface integrity. The medium is not
accessed during the execution of this command.
The WRITE BUFFER command is also used to download Microcode to the drive.
3.41.1 WRITE BUFFER Command Descriptor Block
Byte Bits
7 6 5 4 3 2 1 0
0 Operation Code (3B)
1 Ignored LUN Mode
2 Buffer ID
3 (MSB)
4
5
Buffer Offset
(LSB)
6 (MSB)
7
8
Parameter List Length
(LSB)
9 Control
3.41.1.1 WRITE BUFFER Command Field Descriptions
Field Bytes Bits Description
Operation
Code 0 The operation code for WRITE BUFFER is 3Bh.
Ignored
Logical
Unit 1 5-7 The LUN field is vestigial from the SCSI-1 standard and is ignored.
MODE 1 0-4 00h = Write header and data.
01h = Write Medium Auxiliary Memory (MAM), EEPROM or flash
data.
02h = Write data only.
04h = Microcode download. Do not write to flash memory.
05h = Microcode download. Write to flash memory.
06h = Microcode download. Do not write to flash memory.
07h = Microcode download. Write to flash memory.
0Ah = Write echo buffer.
Buffer ID 00h = normal access (default)
54h = specifies access to Medium Auxiliary Memory
BUFFER
OFFSET 3-5 For Mode not equal to 01h: The offset from the beginning of the
specified buffer in bytes.
For Mode equal 01h: Set to the Medium Auxiliary Memory as
described in the tables.
PARAMET
ER LIST
LENGTH
6-8
Specifies the amount of data to be sent. A value of 0 is a valid entry
and shall not be considered an error.
This value must be smaller than the difference between the Buffer
Offset and the size of the buffer.
CONTROL 9 See SCSI Command Control Byte Format on page 25.