FIGURE C-11

C.1.14.4 Internal SCSI Subassembly

The internal SCSI subassembly consists of two cable assemblies and two SCSI cards. The SCSI subassembly is attached to the motherboard using an insulation displacement connector (IDC) receptacle attached to a 80-conductor cable. In addition to the SCSI signals, the 80-conductor cable carries diskette drive and system LED signals to the SCSI backplane card. The IDC receptacle mates with a right-angle plug that is mounted on the motherboard.

The 80-conductor cable attaches on the other end to the SCSI backplane card with another IDC connector. The SCSI backplane card incorporates two SCA-2 connectors for mounting the hard drives, a four-circuit power connector to supply 5 Vdc and 12 Vdc power to the hard drives, a 34-pin diskette drive signal connector, and a green, right-angle LED.

A 68-conductor cable exits the SCSI backplane card, carrying 27 SCSI signals and the Termpower to the internal CD-ROM drive (or tape drive). The SCSI backplane card houses the CD-ROM drive connector and three SCSI bus terminators. The Termpower is routed through the SCSI subassembly to connect to the terminators on the SCSI backplane card in support of the multi-host configuration.

shows the functionality of the internal SCSI subassembly.

68-pin external SCSI connector

 

68-pin cable

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IDC connector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CD-ROM drive connector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SCA-2 connector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SCSI bus terminator (3)

 

 

 

 

Motherboard

 

 

 

 

 

 

 

 

 

 

 

 

 

IDC connector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SCA-2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Drive

 

 

 

 

 

 

 

 

 

connector (2)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

power

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Diskette

 

 

 

 

IDC connector

 

 

 

 

 

 

 

 

 

 

 

signal

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SCSI

 

 

 

 

 

 

 

 

 

 

 

 

80-conductor cable

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

controller

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Test edge connector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SCSI bus

 

 

 

 

 

 

 

IDC receptacle connector

Board-mounted right-angle IDC plug

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

FIGURE C-11SCSI Subassembly Functional Block Diagram

C-32Sun Ultra 60 Service Manual • August 2001

Page 232
Image 232
Sun Microsystems 60 service manual Internal Scsi Subassembly, Figure C-11 Scsi Subassembly Functional Block Diagram