OAK SCSI 4 User manual

16 Bit SCSI Controller Card
Hard Disc Drives
User Guide

Neither the whole nor any part of the information contained in or the products described in this
manual may be adapted or reproduced in any material form without the prior written
permission of Shawbury Computers Limited (Oak).
The products described in this manual are subject to continuous development and
i mprovement. All information of a technical nature and particulars of the products and their
uses are given in good faith. However, it is acknowledged that there may be errors or
omissions in this manual.
All correspondence should be addressed to:
Customer Support (SCSI)
Oak
Cross Park House
Low Green
Rawdon
Leeds
LS19 6HA
All maintenance and service on the products described in this manual must be carried out by
Oak or their authorised agent. Oak can accept no liability for loss or damage whatsoever
arising from the use of any information or particulars in, or any error or omission in this
manual.
No responsibility is accepted for the installation of the Hard Disc and podule, or for any
consequential damage which results from incorrect use.
Oak is a trademark of Shawbury Computers Limited.
Archimedes, Risc OS and R140 are trademarks of Acorn Computers Limited.
All other trademarks acknowledged.
Issue 1.3
0 Copyright Oak 1989/1990

WARNING (External Drives):
The winchester drive must be earthed
I MPORTANT
The wires in the mains lead for the winchester drive are coloured in
accordance with the following code:
Green & Yellow

Earth
Blue

Neutral
Brown

Live
If the mains socket outlet available does not match the supplied
moulded 13A plug, either a different lead must be obtained, or the plug
should be cut off, disposed of, and the appropriate plug fitted and
wired as described below.
As the colours of the wires may not correspond with the markings
identifying the terminals in your plug, proceed as follows:
The wire coloured Green and Yellow must be connected to the
terminal in the plug which is marked by the safety earth symbol
or the letter E, the colour Green, or Green and Yellow.
The wire coloured Blue must be connected to the terminal marked with
the letter N, or coloured Black.
The wire coloured Brown must be connected to the terminal marked
with the letter L, or coloured Red.

Guidelines for safe operation
To ensure safe and reliable operation of your SCSI controller card and
winchester drive, the following guidelines should be observed.
Internal winchester drives should never be operated without a fan fitted
and working inside the Archimedes.
Keep the winchester at a room temperature of 5-35°C (41-95°F) and at
a relative humidity of 15-90% (non-condensing).
Avoid sudden changes of temperature, exposure to direct sunlight, heat
sources and moisture.
Do not block any ventilation slots in the winchester case, or the fan
outlet holes, and make sure that there is enough space around the
winchester for air to circulate.
Do not poke any objects through the ventilation holes in the winchester
casing.
Route cables sensibly to avoid kinking and tripping. Do not use the
cables to lift drives or controller cards.
Make sure you understand the fitting instructions before embarking on
installation. If in doubt, contact your dealer or Oak customer support.
Keep the original packing in case you need to transport your
equipment.
Never operate External winchesters with the cover removed.
Bear in mind that winchester drives are extremely fragile, and that
bumps and shocks can cause serious damage to the heads and disc
surfaces.

Contents
Conventions used in this manual

1
What is SCSI?

3
Installing the Hard Disc & Podule

5
Initial Testing

11
Using Your Oak SCSI Winchester

13
* Commands

15
Using SCSIFORM - Format/Configure Utility

29
Running Illegal Software

41
Booting from the SCSI drive

43
Trouble Shooting

44

Conventions used in this
manual
The mouse buttons are referred to by name using the standard Acorn
convention of:
Pressing and releasing a mouse button is known as `clicking'.
Pressing and releasing a mouse button twice in quick succession is
known as `double-clicking'.
Pressing and holding down a mouse button whilst moving the mouse is
known as `dragging'.
Text to be typed in at the keyboard will be shown in the following font:
*help commands
Special keys on the keyboard and mouse will be shown in square
brackets
eg: [ Return]
Page 1

In descriptions of syntax for *commands, the following conventions
will be used.
< ... >

indicates that an actual value must be substituted,
e.g. < f ilename> means that an actual filename must be supplied.
[ . . . ]

indicates that the item enclosed in square brackets is optional,
e.g. *WPROT

< D >

[ U ]

means that the letter U is an optional
parameter to the WPROT command.
I
indicates an option.
e.g. 0 | 1 means that the value 0 or 1 must be supplied.
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2

What is SCSI?
The following brief description of SCSI does not set out to fully cover
SCSI in depth, but rather deals with SCSI in the context of the
Archimedes and the Oak SCSI controller card.
SCSI, (Small Computer Systems Interface) is a high speed interface
designed to connect a variety of peripherals to a host system (the
initiator - so called because it initiates the SCSI commands). Up to 7
devices may be attached to one host, with each device having a unique
SCSI ID number (0 to 7). The default ID for the Oak SCSI controller
card is 7, leaving 0-6 free for peripherals. One SCSI device may
actually be responsible for controlling more than one peripheral. For
example, the Adaptec hard disc controller card can control two ST506
winchesters, but appears as just one SCSI device, with the two drives
being differentiated by the Logical Unit Number [LUN]. Thus the first
drive may appear to the initiator as SCSI ID 3, LUN 0 and the second
drive as SCSI ID 3, LUN 1.
SCSI devices are `daisy chained' together, i.e. they are all connected
together in parallel to one 50 way bus. SCSI devices should therefore
provide 2 SCSI connections, effectively a `SCSI in' and a `SCSI out'
to allow further devices to be attached to the bus.
SCSI winchester drives include their own `in built' winchester
controller which is optimised for that particular drive, and thereby
allows the winchester manufacturer to employ a variety of techniques
to maximise both the storage capacity and the speed of the drive. Thus
SCSI winchesters are generally much faster than their equivalent
ST506 counterparts which interface to a standard ST506 controller.
Also, because of their on-board `intelligence' SCSI winchesters are
much easier to set up and use as they deal with their own defect
management, and `know' their own shape (No of heads, cylinders etc).
SCSI has an 8 bit data bus, and is capable of transferring data at a
maximum rate of roughly 2Mb/sec in asynchronous mode. This
maximum figure is limited in practice by the performance of the
peripheral. For example, a fast, modern 20Mb winchester would
typically be able to achieve a data transfer rate of 650Kb/sec
(compared with a 20Mb ST506 winchester at roughly 300Kb/sec), and
a fast 300Mb winchester would achieve close to 1.5Mb/sec. On the
bulk of SCSI systems, however, performance is degraded most by the
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