TargetDevice Comment
Internal disks Up to two 3.5-inch x 1.6-inch disks
(9.1-Gbyte or 18-Gbyte). All internal disks
are UltraSCSI-compliant.
Internal CD-ROM drive Optional 644-Mbyte SunCD 32X speed;
photo CD compatible. Headphone jack with
volume control. CD-ROM drive is a narrow
SCSI device.
Internal tape drive(s) Refer to product guide.
External SPARCstorageUniPack Refer to product guide.
External SPARCstorageSixPack Refer to product guide.
C.1.11.3 External Cables
External UltraSCSI-compliant SCSI cables have an impedance of 90 ohm (+/- 6 ohm)
and are required for UltraSCSI interface. Sun’s implementation of UltraSCSI requires
that the total SCSI bus lengthbe limited to no more than approximately 20 feet (6
meters) with up to 12 Sun compensated devices. Due to the considerably short bus
length, an approximately 32-inch (0.8-meter) UltraSCSI-compliant external cable is
supported (part number 530-2883) in addition to an approximate 6.5-foot (2-meter)
UltraSCSI-compliant external cable (part number 530-2884).
C.1.11.4 Internal SCSI Subassembly
The internal SCSI subassembly consists of two cable assemblies and two SCSI cards.
The SCSI subassembly is attached to the main logic board using an insulation
displacement connector (IDC) receptacle attachedto a 80-conductor cable. In addition
to the SCSI signals, the 80-conductor cable carries system LED signals to the SCSI
backplane card. The IDC receptaclemates with a right-angle plug that is mounted on
the main logic board.
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 connectorto supply 5 VDC and
12 VDC power to the hard drives, 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 oneSCSI bus terminator. The Termpower
is routed through the SCSI subassembly to connect to the terminator on the SCSI
270 Sun Enterprise 220R Server Service Manual ♦January 2000, Revision A