|
Auto start and delay pins
These pins control when and how the drive spins up. When both Auto start and Auto start delay are enabled, the drive start will be delayed by a period of time multiplied by its own SCSI address. If Auto
start is disabled, these jumpers will be ignored.
Write protect pin
If the write protect jumper is installed, the drive will prohibit
SCSI commands that alter the customer data area portion of the media
from being performed. The state of this pin is monitored on a per
command basis. See the Ultrastar 9ZX interface specification for
functional details.
Option block mode pin
The option block mode pin is used to modify the function of the front
option jumper block. When the option block mode pin is not grounded
the pin function of the front option jumper block will be as defined by
the upper portion of the referenced figures. When the option block mode
pin is grounded the pins (25, 27, 29, 31) will be redefined to control
what is referred to as 'alternate mode'. Alternate mode is reserved for
future use.
Disable T.I. sync. negotiation pin
If a disable target initiated synchronous negotiation pin is grounded
then an initiator is required to start a negotiation handshake if
synchronous and/or wide (double byte) SCSI transfers are desired.
Please refer to the Ultrastar 9ZX interface specifications for more
details on this feature.
Disable SCSI parity pin
Grounding this pin will disable SCSI parity checking.
Disable unit attention pin
Grounding this pin will disable the drive from building unit attention
sense information for commands immediately following a power on reset
(POR) or SCSI bus reset. Any pending unit attention conditions will also
be cleared at POR or SCSI reset times.
Customizing pin
Enable narrow mode
Jumpering pin 13 to 14 will cause the 68 pin differential or the 80 pin
SCA-2 to operate in a single byte mode. The drive will not negotiate
for "wide" (double byte) operation. The drive will terminate the
unused upper byte and upper byte parity on the SCSI bus.
Enable active termination
Single ended 68 pin models are available with on card SCSI bus
active terminators. The active termination feature can be enabled by
installing a jumper between pins 13 and 14 of the front option jumper
block or connecting pins 9 and 11 of the auxiliary connector on 68 pin
SCSI models. SCA-2 80 pin and 68 pin differential have no termination. |
