Function Description - Seagate ST39173N Product Manual

40
8.1.2

Function description

J2
jumper
installation Jumper function description
TE (Applies only to "N" and "W" models)
On With the jumper installed, the On-board (non-removable) terminator circuits are enabled
(connected to the I/O lines). Default is jumper installed.
Off Terminator circuits not enabled (not connected to I/O lines).
SE (Applies to "LC" and "LW" models only)
On Forces drive to use single-ended I/O drivers/receivers only.
Off Drive can operate on the interface in low voltage differential mode or single-ended,
depending on the voltage state of the I/O "DIFFSENS" line. Default is no jumper on.
DS ME (Applies to all models)
Off Off Spindle starts immediately after power up—Default setting.
Off On Drive spindle does not start until Start Unit command received from host.
On Off Spindle Startup is delayed by SCSI ID times 12 seconds after power is applied, i.e., drive 0
spindle starts immediately when DC power connected, drive 1 starts after 12 second delay,
drive 2 starts after 24 second delay, etc.
On On Drive spindle starts when Start Unit command received from host. Delayed start feature is
overridden and does not apply when ME jumper is installed.
WP (Applies to all models)
On Entire drive is write protected.
Off Drive is not write protected. Default is no WP jumper installed.
PD (Applies to all models)
On Parity checking and parity error reporting by the drive is disabled.
Off Drive checks for parity and reports result of parity checking to host.
Default is PD jumper not installed.
RES (Applies to all models)
Off Reserved jumper position. Default is no jumper installed.
TP2 TP1 (Does not apply to "WC" model)
Off Off No terminator power is connected to drive terminators or SCSI bus I/O cable*.
On Off Drive supplies its own terminator power only. Jumper on this position is factory default.
Off On Drive supplies power to SCSI bus I/O cable*; none to internal terminators. When drives have
differential I/O circuits, a jumper on the TP1 position may be needed to power external termi-
nators (see system documentation). The "WD" drives have differential I/O circuits which
have no terminator circuits on the drive.
On On Drive supplies terminator power to itself (internal connection) and to SCSI bus I/O cable*.
This is a legal jumper setting.
TP1 and TP2
"Position A" (Applies only to "N" and "W")
On This horizontally positioned jumper across the two TP positions furthest from the PCB edge,
connects terminator power from SCSI bus I/O Termpower cable* to the drive's internal termi-
nators (for single-ended I/O only).
Off See above explanations for TP jumpers.
*See Figure 7d for pins used for Termpower.
Barracuda 9LP Product Manual, Rev. C