
24 ST43401N/ND, ST43402ND User’s Manual, Rev. B
Figure 8. ST43401N/ND control board jumpers
Pin 1
Pin 1
Pin 1
Terminator Resistor-Paks (3)
(must be installed if drive is at
either end of the daisychain)
1
2
3
4
Terminator Power Source Jumper
Assign the terminal power jumpers as shown below.
2
1
4
3
J01
Internal terminator power source.
External terminator power source.
Internal terminator power to I/O.
Write Protect/Enable (WRT)
Fault LED connector
Ready LED connector
Slave Select (SLV)
J4A
Write Protect/Enable (WRT)
WRT
SLV
Write protect (disable writing)
Write enable (enable writing)
Slave Select (SLV)
Master (master drive for spindle sync)
Slave (slave drive unless selected as
the master by a SCSI command)
Spinup Delay Option (SDO)
Start Command Option (SCO)
SCSI Bus Parity Check Option (SCPAR)
Sweep Cycle Option (SWP)
J4B
Spinup Delay Option (SDO)
Start Command Option (SCO)
Immediate spinup
(if the Start Command Option jumper is disconnected)
Spinup delay equal to the SCSI bus ID multiplied
by 10 seconds (if the Start Command Option
jumper is disconnected)
Start spindle according to the Spinup Delay
Option jumper
Start spindle after the SCSI bus sends a Start
Unit command
Enable parity check of SCSI bus data
Ignore parity
Sweep Cycle Option (SWP)
Disable sweep cycles (recommendation – sweep cycles
should be enabled at the system or subsystem level)
Enable sweep cycles at the drive level
Unit Selectors
J7
ID3
ID2
ID1
ID0
Motor (MTR)
Ground (GND)
Key (no pins)
Spindle Sync Clock – (SSCLK–)
Spindle Sync Clock + (SSCLK+)
ID3 ID1
ID2 ID0
MTR
Unit Select ID = 0
Unit Select ID = 1
Unit Select ID = 2
Unit Select ID = 3
Unit Select ID = 4
Unit Select ID = 5
Unit Select ID = 6
Unit Select ID = 7
SCSI Unit Selectors
Unit Select ID = 8
Unit Select ID = 9
Unit Select ID = A
Unit Select ID = B
Unit Select ID = C
Unit Select ID = D
Unit Select ID = E
Unit Select ID = F
Spindle
Sync Pins
= Jumper
connected
= Jumper not
connected
= Non-applicable
jumper (not
relevant to the
option discussed)
SDO SCPAR
SCO SWP
SCSI Bus Parity Check Option (SCPAR)