Seagate MEDALIST 1080SL Product Manual page 71

Medalist 1080sl SCSI Product Manual, August 1995
Bytes
7 6
0 0 0
1 LUN
2
3–5
6–8
9 0 0
Byte 1 If the mode bits contain 000
drive buffer with a 4-byte header that contains all zeros. This
mode is called write combined header and data .
If the mode bits contain 010
drive buffer without the header. This mode is called write data .
If the mode bits contain 101
to the drive buffer, and the drive saves the microcode in flash
memory. The drive uses the new microcode for all future opera-
tions. This mode is called download microcode and save .
After the microcode has been successfully downloaded, the
drive generates a unit attention condition of microcode has been
downloaded for all initiators except the one that issued the
current Write Data Buffer command.
All other settings for the mode bits are reserved.
Byte 2 The buffer ID is not supported and must always be zero.
Byte 3–5 The buffer offset is added to the starting address of the
buffer to determine the destination of the first data byte. The
bytes that follow are placed in sequential addresses. If the
sum of the buffer offset and the transfer length exceeds the
buffer size reported by the Read Data Buffer command (see
Section 3.5.9), the drive generates a check condition status
and the initiator does not transfer any data. This field is
ignored if the mode bit is 101
Bytes 6–8 The parameter list length field specifies the maximum num-
ber of bytes the initiator transfers. If the initiator transfers
the 4-byte header, the transfer length includes the header.
If the transfer length is zero, no data is transferred to the
drive buffer; this is not considered an error.
Bits
5 4 3 2
1 1 1 0
0 0
Buffer ID (00 )
H
Buffer offset
Parameter list length
0 0 0 0
, the initiator transfers data to the
B
, the initiator transfers data to the
B
, the initiator downloads microcode
B
.
B
61
1 0
1 1
Mode
0 0