Sun Microsystems Netra T4 AC100, Service And System Reference Manual

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Chapter 10 Functional Description 10-35
10.2.15.3 External Cables
External Ultra SCSI-compliant SCSI cables have an impedance of 90 ohm (+/- 6 ohm)
and are required for Ultra SCSI interface. The Sun implementation of Ultra SCSI
requires that the total SCSI bus length be limited to no more than approximately 6 m
(20 ft) with up to twelve Sun compensated devices.
Owing to the considerably short bus length, two Ultra SCSI-compliant external
cables are supported, 800 mm (32 in.) and 2 m (6.6 ft).
Note – Consult your authorized Sun sales representative or service provider to
order Ultra SCSI-compliant external cables.
There is also an external SCSI connector on the rear panel for legacy peripheral
devices.
10.2.16 SuperI/O
The Netra T4 system uses a SuperI/O ASIC to interface to the parallel port. The
SuperI/O ASIC also:
■
Provides the TOD/ID SEEPROM
■
Interfaces with the power supply