Sun Oracle Storage Tek T10000, Справочное руководство

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E20425-01 • Chapter 4 Commands 235
Write Buffer Command
Notes:
• The process of updating firmware is called a download. A successful
download writes new firmware to memory and resets the tape drive after the
final Write Buffer command completes. A failure of the writing process causes
the drive to retain the current version of the firmware. A CRC check is
performed over the entire download after the last command. A Unit Attention
condition is set following a successful firmware download.
• The tape drive must be unloaded to perform this command.
• Blocks of firmware data must be transferred in sequential order. Each block
except the last block transferred must be 262,144 bytes long. A parameter list
length of 0 is allowed for mode 111b only.
• For compatibility with existing systems, mode field values 100b and 101b are
accepted as equivalent to 110b and 111b. New implementations should not
use 100b and 101b.
• The sequence of Write Buffer commands for a code download should be
uninterrupted by other commands. It is suggested that the device be reserved
during a code download.
Parameter Value
Mode Indicates the type of download:
06h = Download Microcode with Offsets
Multiple transfers are required to download the microcode.
The first Write Buffer command must contain data for the start
of the image. Subsequent Write Buffer commands must
transfer data in sequential order.
This mode is used for all Write Buffer commands in a
download except for the last one.
07h = Download Microcode with Offsets and Save
This mode is used only once per download. It is used in
conjunction with the Download Microcode with Offsets (110b)
mode to indicate the last Write Buffer command of a
download. This indicates that the download is finished and the
microcode should be written to memory. A parameter list
length of 0 is allowed for this mode.
0Ah = Write echo buffer
Buffer ID Indicates the region of memory to be modified

(must be 00h).
Buffer Offset

Offset from start of the buffer area (this field is ignored).
Parameter List Length

Number of bytes to transfer.