64 write buffer command, Write buffer command – Seagate Fibre Channel Interface User Manual
Page 349
Fibre Channel Interface Manual, Rev. D
335
12.64
Write Buffer command
The Write Buffer command may be used in conjunction with the Read Buffer command as a diagnostic function
for testing the disc drive’s data buffer memory and the FC-AL integrity. When used in a diagnostic mode, the
medium is not accessed during the execution of this command. Additional modes are provided for downloading
and saving executable microcode. The function of this command and the meaning of the fields within the Com-
mand Descriptor Block depend on the Mode field.
Field definitions (listed alphabetically)
Buffer ID
Implemented only by drives that support modes 110b and 111b.
Buffer Offset
Implemented only by drives that support modes 110b and 111b.
Byte Transfer Length
Use a Read Buffer command with mode bits set to 011b to get the drive buffer capacity to use with the Write Buffer com-
mand.
Control
See Control Bytes in Section 11.2.1.6.
Mode
Defined in the following table and in the referenced sections.
Check with your drive’s Product Manual, Volume 1, to see which modes are supported by the drive.
Table 227: Write Buffer command (3Bh)
Bit
Byte
7
6
5
4
3
2
1
0
0
0
0
1
1
1
0
1
1
1
0
0
0
0
0
Mode
Reserved
2
Buffer ID
3
(MSB)
4
Buffer Offset
5
(LSB)
6
(MSB)
7
Byte Transfer Length
8
(LSB)
9
Control
3Bh
Table
number