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.
Page
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
Page 3

inability of the initiating system to deal with such high data transfer
rates. Using an Archimedes with the Oak SCSI controller card avoids
this degradation of performance. The Oak card buffers the 8 bit data
from the SCSI bus in order to perform 16 bit memory transfers to and
from the Archimedes, thereby vastly reducing the normal handshaking
overhead.
SCSI imposes no restrictions on the numbers of any particular type of
device (up to a maximum of 7) on the SCSI bus; however, the Filecore
module within Risc OS allows a filing system (SCSIFS in the case of
the Oak SCSI controller card) to have only 4 winchesters, and also
li mits the capacity of each winchester to 512Mb. Thus a total of 2
gigabytes of winchester storage is achievable under the SCSIFS filing
system.
Non-winchester SCSI devices (e.g. tape streamers, CD ROMs) may
also be addressed by the Oak SCSI controller card via SWIs which
allow low level access to SCSI commands, or via high level software
available separately such as the !OakTape tape backup software from
Oak.
Page 4

Page 5
I
nstalling the Hard Disc &
Podule
Warning
No special skills are required to fit the Hard Disc Drive. However, the
suppliers can accept no responsibility for any damage which may
result from incorrect installation. If in doubt, contact your supplier.
Tools
The only tools required are a number 2 cross-head screwdriver and a
large flat bladed screwdriver (A3000 only). Installation of internal
drives may also require a pair of wire cutters or scissors and a blade.
Safety
Ensure that the Archimedes power supply is switched off and that all
mains supply cords are disconnected before removing any covers. You
are warned that dangerous voltages exist in the Archimedes power
supply unit. Do not insert any objects into the ventilation holes of the
PSU case.

I nstalling the Podule
(300/400/R140 Series Machines)
Disassembly
Unplug the mains power cord and all peripherals (including the
keyboard) from the Archimedes. The cover of the Archimedes is held
in place by 5 screws, three on the rear of the case above the podule
slots, and one at either side of the case close to the moulded plastic
front piece (as shown below). Remove all 5 screws and slide the lid
rearwards and off.
Positioning
The SCSI podule may be fitted in any of the four possible podule
positions. Remove the blanking plate related to your chosen podule
position from the rear of the Archimedes by undoing the screw at each
side. If you have removed a double width blanking plate, use the single
width blanking plate, T-Piece and screws supplied with your SCSI
card to build the podule backplate up to double width.
Carefully insert the SCSI card (component side up) into the desired
backplate socket on the Archimedes, making sure that the SCSI card is
held horizontally. The backplane is supported by a stout metal strip;
however it is wise to give the backplane additional support with one
hand whilst inserting the SCSI card. If there are no other podules fitted
in the Archimedes, it may be necessary to loosen the two screws at the
ends of the metal strip that reinforces the backplane, and carefully
reposition the backplane so that the SCSI card can be mounted flush
with the back of the Archimedes. Fasten the podule backplate
assembly to the back of the Archimedes with a screw at each end and
tighten the screws securing the backplane.
Page 6

Page 7
If your kit contains an internal winchester drive, move on to the section
headed installing an internal winchester. If your kit contains an
external winchester drive, replace the cover of the Archimedes (don't
refit the screws yet) and move on to the section headed installing an
external winchester.

I
nstalling the Podule (A3000)
On the A3000, the SCSI card is mounted externally at the rear of the
machine. The SCSI card is housed in a metal case with a mounting
bracket which bolts to the rear of the A3000. Ensure that the A3000 is
disconnected from the mains. Holding the SCSI card horizontally with
the angle bracket pointing upwards and towards the A3000, push the
card into the socket on the left hand side of the A3000 (when looking
from the rear). Check that the card is pushed fully home and then
screw the angle bracket to the rear of the A3000 with the 2 screws
provided.
Now move on to the section headed Installing an external winchester.
Page 8

I
nstalling an internal
winchester
Take off the plastic front panel of the Archimedes by removing the 3
self tapping screws underneath the front of the Archimedes, and the 1
at each side (normally obscured by the cover). The winchester
mounting brackets are supplied already fitted to the winchester. Mount
the winchester assembly (with the 50 way socket to the rear of the
Archimedes) using the 2 small self tapping screws provided, to the
metal bracket inside the Archimedes, next to the floppy disc drive.
(Owners of certain early Archimedes machines may find that the 2
holes are actually tapped - if this is the case, do not worry, but use the
self tapping screws anyway.)
Attach the power cable (terminated in a white, 4 way plastic connector)
from the Archimedes power supply to the winchester. (You may need
to carefully cut a nylon cable tie to release this power cable.)
Connect the 50 way ribbon cable between the winchester and the pin
connector on the SCSI controller card (making sure that polarising
bumps/slots mate correctly at the winchester end, and that the bump on
the 50 way cable points to the front of the Archimedes at the SCSI card
end -basically, if there is no twist in the ribbon cable, it's correct!).
Carefully remove the Archimedes badge from the Archimedes plastic
front panel (prising it off with a blade). Stick the badge supplied with
the winchester in its place. A few very early Archimedes machines
have a non standard spacing between the LED holes. If this is the case
with your machine, you will need to scrape some ink off the back of
the badge to allow the LED to be visible. Stick the LED on the trailing
lead from the winchester into the vacant hole behind the badge, using
bath sealant or any suitable adhesive.
If difficulty is experienced in locating the LED in its hole, the darker
coloured plastic front of the assembly may be detached by removing
the 2 recessed self tapping screws.
Screw the front panel back onto the Archimedes, and then refit the
cover (don't screw the cover to the Archimedes yet). Now move on to
the section headed Initial Testing.
Page
9

I nstalling an external
winchester
Connect the external winchester to the back of the SCSI controller card
using the 50 way ribbon cable provided, making sure that the
polarising bumps on the cable sockets mate with the slots on the plugs
at the rear of the Archimedes and the Winchester. There are two 50
way plugs on the rear of the winchester drive to allow other SCSI
devices to be daisy chained. These plugs are wired in parallel and so
either can be used.
Now move on to the section headed Initial Testing.
Page
1 0

I nitial testing
Power up the Archimedes. If the Archimedes does not start up
correctly, turn everything off and recheck all connections. If the
Archimedes still does not start up, refer to the section headed
`troubleshooting'. Note that each card and drive has been thoroughly
tested at the factory, and so any faults at this stage are most likely to be
caused by incorrect installation, a faulty backplane or faulty
Archimedes.
If the Archimedes does start up correctly, switch on the external
winchester (if fitted). You should hear the drive of the internal or
external winchester spin up to speed and make a few `seek' noises as it
initialises itself.
The winchester is supplied already formatted, and the SCSI card
already initialised, and so the system should now be ready for
configuring. DO NOT USE THE SCSIFORM PROGRAM AT THIS
STAGE. All the options you can set using SCSIFORM have already
been set at the factory! Using SCSIFORM before you are familiar with
the system is more likely to undo necessary settings rather than do
anything useful - you have been warned!
There is no need to type
*configure harddiscs 1 -this
command refers to ST506 winchesters running under ADFS. Only use
this command if you also have an ADFS winchester. Also note that the
*configure drive command refers only to ADFS drives, so this
is best left set to `0' unless you have an ADFS winchester.
Various configuration values must now be set. Obtain a command line
prompt (e.g. by pressing F12 from the desktop) and type:
*configure scsifs 1 [Return]
then hold down [ Ctrl ]

whilst pressing and releasing [
Break ]
This enables SCSIFS - the filing system provided by the Oak SCSI
controller card. Next, type:
*configure scsidrive 4 [Return]
This makes sure that SCSIFS initially logs on to drive 4 when selected.
Page 1 1

You will then have to decide how much memory to assign to the SCSI
directory cache. The value will depend on the amount of memory
available in your machine. A value of 4K is recommended: higher
values will allow more directories to be cached in RAM, a lower value
will allow fewer directories to be stored in RAM. To configure this
value, obtain a command line prompt and type:
*configure scsidircache 4K [Return]
or replace the 4K with the value you have decided on.
The next decision is whether or not to have the root directory of the
winchester set as the current directory at power on (this is equivalent to
ADFS's configure dir/nodir, and is effective only if the configured
filing system is SCSIFS). If you want the root directory set, type:
*configure scsidir [Return]
otherwise type:
*configure scsinodir [Return]
You may want the default filing system of the Archimedes at power up
to be SCSIFS (e.g. if you want to run a boot file from your SCSI
winchester). If this is the case type:
*configure filesystem scsi [Return]
To bring these configuration values into effect, hold down
[ Ctrl ] whilst pressing and releasing [
Break ]
You may now enter the desktop and click on the new SCSI winchester
icon. A directory viewer should open. Open up the sprites directory
and double click select on one of the files. If a picture is loaded up
onto the screen. all is well and you may replace the screws in the
Archimedes case.
Page 1 2

Using your Oak SCSI
winchester
I n use, the SCSI filing system behaves as a normal Archimedes filing
system, (e.g. ADFS), and is operated from the desktop in exactly the
same way. The icon on the icon bar for the SCSI winchester appears as
a standard winchester icon with the legend SCSI, and the drive number
below.
Clicking menu on the SCSI icon brings up a menu of 4 items:
Name disc
This option allows the name of the winchester to be changed. To
change the name of the winchester, wipe across the namedisc option
and either edit the current name or delete and retype it. Note that you
must not have 2 SCSI winchesters with the same disc name, as this
confuses the operating system.
Dismount
This option closes files, unsets directories and parks the heads of the
winchester. (N.B. Oak Winchesters have autoparking heads so this
option is normally only used for making sure that all files are closed.)
Verify
This option checks that the entire disc is readable.
Free
This option displays the amount of used and unused space on the
winchester.
Page 1 3