Configuration and Jumper Options
Pin Numbers refer to the Option Jumper Block)
SCSI ID Selection
Up to sixteen devices (the host and fifteen targets) can be attached to the SCSI bus. These are selected with jumpers on the Option Jumper Block or on Auxiliary Connector J1B (use either but not both); see the Note below the J1B drawing for J1B usage. In multiple-device systems, each device must have its own Unique SCSI ID. The SCSI ID (drive address) jumpers are identified as ID0, ID1, ID2, and ID3. ID selection is binary, as shown below.
SCSI ID ID3 ID2 ID1 ID0
0 (Default) out out out out
1 out out out in
2 out out in out
3 out out in in
4 out in out out
5 out in out in
6 out in in out
7 out in in in
8 in out out out
9 in out out in
10 in out in out
11 in out in in
12 in in out out
13 in in out in
14 in in in out
15 in in in in
If terminators are installed at RN1, RN2, and RN3 (default), the drive provides termination for the SCSI interface. If the terminators are not installed, the drive does not provide interface termination.
SCSI terminators are installed only in the end devices on the SCSI cable; remove the terminators from each of the other devices. The SCSI Host Adapter card and the last drive in the chain should have terminators.
W1 and W2 select the source of power (+5V) for the interface terminators; W3 controls the drive supplying +5V to the bus.
W1 W2 W3
Y N - Drive provides terminator power. (Default)
N Y - Host provides terminator pwr via J1 pin 26
to RN1 and RN2
- - Y Drive supplies +5V to the bus via J1 pin 26.
A user-supplied LED may be connected to Remote LED (Pins 1 and 2).
Jumpers at SP0 (Pins 11 and 12) and SP1 (Pins 13 and 14) control the spindle options.
N N The drive starts the spindle motor at power-on.
Y N The drive waits for a Start Unit SCSI command
to start the spindle motor.
N Y Spindle start-up is delayed based on SCSI ID
address (12 seconds per ID)
A jumper at WP (Pins 15 and 16) selects the write protect option.
Jumper The drive is write protected.
No Jumper The drive is not write protected. (Default)
A jumper at PTY (Pins 17 and 18) selects the bus parity check option. The drive always generates
parity regardless of this option.
Jumper SCSI interface parity checking disabled.
No Jumper SCSI interface parity checking on. (Default)
Spindle Sync Signals
Use of the MSYNC and SSYNC signals is optional. These signals are used as spindle synchronization reference.
Auxiliary Connector J1B
Note: J1B is sampled at initialization for jumpers on pins 7-8, 5-6, 3-4, and 1-2 for SCSI ID3, ID2, ID1, and ID0 respectively; these connections (if not jumpered) are then released for the following usages:
A dash character (-) at the end of a signal name indicates that it is asserted at the low level (i.e., active low) and negated at the high level.
Drive Fault (XTFALT-)
Output signal negated (Default); indicates no drive fault.
Output signal asserted; indicates a drive fault condition.
Slave Sync (SSYNC-)
Use is optional; used as spindle synchronization reference.
Open collector output; used to drive a user-supplied LED to indicate the drive is active.
Logic ground; provides signal ground.
+5 Volts (+5V)
5 VDC (1A max); used to drive external LEDs.
Write Protect (FAULT-)
Input signal negated (Default); drive is not
Input signal asserted; drive is write protected.