For a single-ended cable, a 50-conductor flat cable or a 25 twisted pair cable can be used, with a
maximum length of 6.0 meters and a stub length not to exceed 0.1 meters.
This file has a maximum internal stub length of 0.072 meters on all SCSI signals except -RST; the
-RST signal has an internal stub length of 0.096 meters. To remain compliant with ANSI, the
SCSI bus cable must not add more than 0.028 meters additional stub length to all SCSI signals
except -RST, and no more than 0.004 meters additional stub length to -RST.
SCSI Bus Electrical Characteristics
Note: The drive incorporates the Western Digital WD33C93B SCSI Interface Controller and
conforms to the ANSI/SCSI Interface standard.
ELECTROMAGNETIC COMPATIBILITY
The Drive meets the following EMC requirements when installed in the user system and exercised
with a random accessing routine at maximum data rate:
United States Federal Communications Commission (FCC) Rules and Regulations. Part 15,
Subject J-Computer Devices "Class B Limits".
European Economic Community EEC directive #76/889 related to the control of radio
frequency interference and the Verband Deutscher Elektrotechniker (VDE) requirements of
Germany (COP).
START AND STOP TIMES
Time Nominal Maximum
Power Up 2.0 sec 2.4 sec
Start Unit 19.5 sec 1 min
Stop 9 sec 12.5 sec
During the start sequence diagnostics are performed and are divided into two sections. Power-up
pre motor-start diagnostics test the static RAM (control store memory), post motor-start
diagnostics test the data buffer, upload the code, perform channel testing and 'Reassign in
Progress' operations. For more information on diagnostics see the 0663 Disk Drive SCSI
Specifications.
If a Reset is issued before the drive is ready, the power-on sequence starts again. Otherwise,
when a Reset is issued the present state of the motor is not altered.
A timeout of one minute or more is recommended for the Start Unit command. This allows the
system to take advantage of the extended ERP that the drive does in order to successfully start
up.
Note: It is the integrators' responsibility to ensure that equipment into which this drive is fitted
meets the relevant regulatory requirements (EMC etc).
MECHANICAL SPECIFICATIONS