Seagate Ultra 320 - Manual (Page 129)

Parallel SCSI Interface Product Manual, Rev. A 115
[1] See Table 49 for the format of the SPI L_Q information unit.
[2] See Table 46 for the format of the SPI Command information unit.
[3] See Figure 16.
[4] See Figure 18.
Figure 15. SPI information unit sequence during initial connection
SPI L_Q
(always Init to Targ)
(logical connect)
DT DATA OUT
SELECTION
SPI COMMAND
(always Init to Targ)
MESSAGE
IN
(QAS or WDTR)
MESSAGE
OUT
BUS
FREE
(physical
disconnect)
DT DATA IN
(to SPI L_Q/DATA [3]
or
SPI L_Q/STATUS [4])
(logical disconnect)
Attention
Condition
[1]
[2]