SCSI Commands: 53BWRITE BUFFER Page 2213.41 WRITE BUFFERThe WRITE BUFFER command is used in conjunction with the READ BUFFERcommand as a diagnostic function for testing the data buffer memory of the driveand confirming the SCSI bus or Fibre Channel interface integrity. The medium is notaccessed 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 BlockByteBits7 6 5 4 3 2 1 00 Operation Code (3B)1 Ignored LUN Mode2 Buffer ID3 (MSB)45Buffer Offset(LSB)6 (MSB)78Parameter List Length(LSB)9 Control3.41.1.1 WRITE BUFFER Command Field DescriptionsField Bytes Bits DescriptionOperationCode0 The operation code for WRITE BUFFER is 3Bh.IgnoredLogicalUnit1 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 flashdata.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 MemoryBUFFEROFFSET3-5 For Mode not equal to 01h: The offset from the beginning of thespecified buffer in bytes.For Mode equal 01h: Set to the Medium Auxiliary Memory asdescribed in the tables.PARAMETER LISTLENGTH6-8 Specifies the amount of data to be sent. A value of 0 is a valid entryand shall not be considered an error.This value must be smaller than the difference between the BufferOffset and the size of the buffer.CONTROL 9 See SCSI Command Control Byte Format on page 25.
