Product manual

40 Barracuda 9 Product Manual, Rev. C
8.1.2 Function description
*See Tables 13, 14, and 15 for pins used for Termpower.
J2 Jumpers Jumper Function Description
TE (Applies only to “N” and “W” models)
On On-board (non-removable) terminator circuits are enabled. (Default)
Off On-board (non-removable) terminator circuits are disabled.
DS ME (Applies to all models)
Off Off Spindle starts immediately after power up. (Default)
Off On Spindle does not start until a Start Unit command is received from the host.
On Off Startup is delayed by SCSI ID times 12 seconds after power is applied. For example:
Drive with SCSI ID of 0 starts the spindle immediately when DC power connected, drive
with SCSI ID of 1 starts after a 12-second delay, drive with SCSI ID of 2 starts after 24-
second delay, etc. Tolerance is plus 3 seconds, minus 0 seconds.
On On Spindle starts when the host sends a Start Unit command. Delayed start feature is over-
ridden and does not apply when the ME jumper is installed.
WP (Applies to all models)
On Drive is write protected.
Off Drive is not write protected. (Default)
PD (Applies to all models)
On SCSI parity checking and parity error reporting by the drive is disabled.
Off Drive checks for parity and reports the results of parity checking to host. (Default)
RES (Applies to all models)
Off Reserved for spindle sync cabling. Pin 9 is the spindle sync reference. Pin 10 is spindle
sync ground. Do not connect a jumper to these pins. (Default)
TP2 TP1 (Applies only to “N,” “W,” and “WD” models)
Off Off No terminator power is connected to the drive terminators or the SCSI bus I/O cable.*
On Off Drive supplies its own terminator power only. (Default)
Off On Drive supplies power to the SCSI bus I/O cable* but not to the internal terminators.
When drives have differential I/O circuits (WD drives), a jumper on the TP1 position
may be needed to power external terminators (see system documentation).
On On Drive supplies terminator power to itself (internal connection) and to the SCSI bus I/O
cable.*
TP2 and TP1
“Position A”
(Applies only to “N,” “W,” and “WD” models)
On This horizontally-positioned jumper (across J2 pins 2 and 4) connects terminator power
from SCSI bus I/O cable* to the drive’s internal terminators (for single-ended I/O only).
See Figures 9 and 10.
Off See above explanations for TP jumpers.