Little Board/P5x Technical Manual
2–37
Table 2– 31. SCSI Interface Connector (J9)

Pin Signal Function Pin Signal Function

2 DB0* Data Bit 0 (LSB) 4 DB1* Data Bit 1
6 DB2* Data Bit 2 8 DB3* Data Bit 3
10 DB4* Data Bit 4 12 DB5* Data Bit 5
14 DB6* Data Bit 6 16 DB7* Data Bit 7
18 DBP* Data Bit Parity 26 TERM
PWR Termination +5V DC
32 ATN* Attention 34 GRO UND Signal Ground
36 BSY* Busy 38 ACK* Transfer
Acknowledge
40 RST* Reset 42 MSG* Message
44 SEL* Select 46 C/D* Control/Data
48 REQ* Transfer Request 50 I/O* Data Direction
25 N/A Key Pin
1-49(odd), 20,22,24,28,30 Ground
Table 2– 328. J9 Mating Connectors

Connector Type Mating Connector

RIBBON 3M 3425-7600
Latching Clip 3505-8050
DISCRETE WIRE MOLEX HOUSING 22-55-
2502
PIN 16-02-0103
SCSI Interface Configuration
Enable or disable the SCSI interface using Setup. Refer to the Setup description beginning on page
2–62.
Interrupt Request Assignment
The SCSI interface is a PCI peripheral and is assigned to a PCI interrupt using the plug-and- play
logic in the BIOS. No user setup is required
Active Terminators
The SCSI interface uses “active terminators” for the SCSI bus. Active terminators draw less current
than 330/220 ohm terminators (standard for non-UltraSCSI interfaces), are less susceptible to
noise, and are required for the high data transfer rates of UltraSCSI. Termination is controlle d by
the SCSI BIOS. There is no user setting.
Only the SCSI devices on each end of the SCSI bus should be terminated.