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Acorn A5000
Module Level Service Manual
Copyright © Acorn Computers Limited 1991
Published by Acorn Computers Technical Publications Department
Neither the whole nor any part of the information contained in, nor the product described in this manual may be
adapted or reproduced in any material form except with the prior written approval of Acorn Computers Limited.
The products described in this manual, and products for use with it are subject to continuous development and
improvement. All information of a technical nature and particulars of the products and their use (including the
information and particulars in this manual) are given by Acorn Computers Limited in good faith. However, Acorn
Computers Limited cannot accept any liability for any loss or damage arising from the use of any information or
particulars in this manual, or any incorrect use of the products. All maintenance and service on the products must be
carried out by Acorn Computers' authorised dealers or Approved Service Centres. Acorn Computers Limited can
accept no liability whatsoever for any loss or damage caused by service, maintenance or repair by unauthorised
personnel.
This product is not intended for use as a critical component in life support devices or any system in which failure could
be expected to result in personal injury.
If you have any comments on this manual, please complete the form at the back of the manual and send it to the
address given there.
ACORN, ARCHIMEDES and ECONET are trademarks of Acorn Computers Limited.
ARM is a trademark of Advanced RISC Machines Limited.
Published by Acorn Computers Limited
ISBN 1 85250 099 9
Part number 0492,059
Issue 1, November 1991
Contents
About this manual
Part 1 - Fault diagnosis and repair
Introduction
Test equipment required
Checking a 'dead' computer
Action if PSU fails
Action if main PCB fails
Action if upgrades fail
What to do next
Checking a partly working computer
1-1
1-1
1-1
1-3
1-3
1-3
1-4
1-4
Before the tests
Safety considerations
Backing up the test disc
Validating the test equipment
Creating a test IDE hard disc
Replacing the customer's hard disc
Connecting the customer's equipment
Saving the customer's CMOS RAM settings
Creating a CMOS test data file
Checking the memory size
About the tests
How to operate the test software
Repairing faults
Running the functional tests
Memory test
Battery backed RAM test
IDE hard disc drive interface test
Hardware check
External port tests
1-4
1-4
1-4
1-4
1-6
1-6
1-6
1-7
1-7
1-7
1-8
1-8
1-8
1-8
1-9
1-9
1-9
1-10
1-10
Disc interface test
Real time test
Audio tests
Video tests
Keyboard and mouse tests
1-11
1-12
1-12
1-12
1-14
Test report
Additional individual tests
1-16
1-16
Hard disc exerciser
Hard disc formatter
After the tests
Performing soak tests
1-16
1-16
1-17
1-17
Performing safety tests
Retesting the unit
Restoring the CMOS RAM settings
Contents
1-1
Issue 1, November 1991 III
1-17
1-17
1-19
A5000
Module Level Service Manual
Replacing the customer's hard disc
1-19
Switching off the equipment
Disconnecting the equipment
Packing
1-19
1-19
1-19
Part 2 - Disassembly and assembly
2-1
Introduction
Removing the top cover
Removing the backplane
Removing cables
Removing the main PCB
Removing the disc drives
Removing the speaker
Removing the front plastic moulding
Removing the power supply unit
Main unit assembly
Power supply unit
Speaker
Disc drives
PCB
Keyboard
2-1
2-1
2-2
2-2
2-2
2-2
2-3
2-3
2-3
2-4
2-4
2-4
2-4
2-4
2-4
Disassembly
Assembly
Mouse
2-4
2-4
2-4
Appendix A - Mouse jig template
A-1
Appendix B - Serial port loopback plug
B-1
Appendix C - Earth continuity testing
C-1
Appendix D - DC insulation testing - class 1
D-1
Appendix E - Monitor adaptor cables
E-1
Appendix F - Main PCB links, plugs & sockets
F-1
Appendix G - Final assembly parts list
G-1
Drawings
Final assembly drawing
iv
Issue 1, November 1991
Contents
About this manual
This manual is a module level service manual for the
Acorn A5000 computer. It is intended as a guide for
suppliers at Acorn Service Centres to enable them to
trace and repair faults at a module level. Suppliers are not
expected to undertake repairs at a component level, as
surface mount technology is used on the printed circuit
boards of the A5000 computer. Any modules which
require component level repairs should be sent to an
Acorn Authorised Central Service Workshop.
This manual supplements the basic information given on
system hardware in the Welcome Guide and Technical
Reference Manual (available for separate purchase).
The operating system is covered at the user level in the
RISC OS User Guide, supplied with certain models (also
available for separate purchase). Programmers and
users requiring a greater depth of information about RISC
OS will also need the following manual:
RISC OS Programmer's Reference Manual
(a boxed set)
This manual is available from Acorn authorised suppliers.
Full details on the Acorn ARM chip set used in the
workstation are given in the Acorn RISC Machine (ARM)
Family Data Manual, ISBN 0-13-781618-9, available from:
VLSI Technology, Inc.
Application Specific Logic Products Division
8375 South River Parkway
Tempe, AZ 85284
USA
602-752-8574
or from the VLSI national distributor.
Contents
Issue 1, November 1991 V
Part 1- Fault diagnosis and repair
Test equipment required
Introduction
This chapter is a guide to the diagnosis and repair at a
modular level of basic faults in the Archimedes 5000
series computer system.
It consists of algorithms to enable you to trace and
remedy faults in a 'dead' computer, followed by
instructions for running the Archimedes functional test
software, which is designed to isolate faults in a computer
which is partly working.
Note: Throughout this chapter the acronym UUT is used
to mean Unit Under Test and the acronym CSW to mean
Central Service Workshop.
•
•
•
•
•
•
•
•
•
•
SAFETY CONSIDERATIONS
WHENEVER ANY SERVICE OR UPGRADE IS
PERFORMED, ENSURE THAT ALL THE FUNCTIONAL
TESTS AND SAFETY TESTS AS DESCRIBED IN THIS
SECTION ARE CARRIED OUT.
FULL FUNCTIONAL AND SAFETY TESTS SHOULD BE
APPLIED IRRESPECTIVE OF THE ORIGINAL FAULT OR
WORK PERFORMED.
FAILURE TO CARRY OUT THE TESTS IN FULL MAY
RESULT IN AN UNSTABLE OR UNRELIABLE UNIT BEING
RETURNED TO THE CUSTOMER.
DANGER
BEFORE ATTEMPTING TO OPEN THE COMPUTER
OR
EXCHANGE EITHER THE PSU (POWER SUPPLY
OR PCB, ENSURE THAT YOU HAVE READ AND
UNIT)
FULLY
UNDERSTOOD ALL THE INSTRUCTIONS IN Part 2 Disassembly and assembly. IN PARTICULAR, ENSURE
THAT YOU DISCONNECT THE COMPUTER, MONITOR
AND PERIPHERALS FROM THE POWER SUPPLY.
UNDER NO CIRCUMSTANCES SHOULD ANY ATTEMPT
BE MADE TO REPAIR OR MODIFY THE PSU. ANY
ATTEMPT TO DO SO WILL INVALIDATE THE ORIGINAL
SAFETY TESTS APPLIED AT MANUFACTURE AND MAY
CREATE A SAFETY HAZARD.
WHEN REFITTING OR FITTING A REPLACEMENT
ASSEMBLY, CHECKS SHOULD BE MADE FOR EARTH
CONTINUITY BETWEEN THE EARTH PIN OF THE MAINS
PLUG AND THE FOLLOWING:
• THE BASE METALWORK
• THE REAR PANELS (INCLUDING BLANKING PANELS
AND CONNECTING PLATE)
• THE TOP COVER
USE AN EARTH CONTINUITY TESTER SET TO 25 AMPS.
FOR DETAILS REFER TO Appendix C - Earth continuity
testing AND Appendix D - DC insulation testing - class 1.
Part 1- Fault diagnosis and repair
•
•
•
•
•
•
DC Voltmeter
A5000 test disc (Acorn part number 0292,824)
a blank 1.6 MB ADFS F format write-enabled, 3.5
inch floppy disc (used as a scratch disc in the disc
interface test)
test IDE hard disc (see the section entitled Creating a
test IDE hard disc on page 1-6)
serial port loopback plug – see Appendix B - Serial
port loopback plug
parallel to video loopback box (0092,800)
headphones (32 ohm impedance)
analogue multisync colour monitor (suitable for super
VGA)
Epson FX80 compatible printer
2 x blank 800K ADFS E format write-enabled, 3.5
inch floppy discs:
• data disc– to store the customer's CMOS RAM
configuration data
• CMOS RAM test data disc– to store the
manufacturer's default CMOS RAM settings (see
the section entitled Creating a CMOS test data file
on page 1-7)
working keyboard (0392,900) and mouse (0183,180)
mouse test jig template (see Appendix A - Mouse test
jig template)
working backplane (0192,004)
standard hand tools, such as screwdrivers and pliers
earth testers (see Appendix C - Earth continuity
testing)
isolation tester (see Appendix D - DC insulation
testing - class 1).
Checking a 'dead' computer
This section describes the initial tests that you should
perform on an apparently 'dead' computer to discover
which module or upgrade is faulty. If the computer is
partially working (i.e. any faults occur after a successful
power-up) go straight to the section entitled Checking a
partly working computer on page 1-4.
To diagnose the faults in a 'dead' computer, refer to the
procedure given in the flowchart, Figure 1-1: Procedure
to check a 'dead' computer on page 1-2. The sections
following describe the actions to be taken when you
have isolated the fault on the computer.
Note: You may need to reconfigure the CMOS RAM to
its original (factory) default setting. Make sure that the
customer is made aware of this.
Issue 1, November 1991
1-1
1-2
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Action if PSU fails
There are three ways in which the power supply unit
(PSU) may fail:
• complete failure
• individual rail failure
• thermal shutdown
The complete failure of the PSU is indicated by the
following symptoms:
• no cooling fan noise
• no green LED on the front panel
• no caps lock LED response when caps lock key
depressed
First check that the fuse in the mains plug has not blown.
To do this, remove the fuse from the plug and check with
a continuity tester. If it has blown then replace only with
a fuse of the same rating (for UK machines this will be
5 Amp). If the new fuse is blown when you switch the
unit on, then return the PSU to an Acorn Authorised
Central Service Workshop (CSW).
If there is an Individual rail failure within the PSU,
various functions of the computer will fail as follows:
• 5V feeds the main PCB, floppy disc and hard disc.
• -5V feeds the backplane expansion connector on pin
A31.
• +12V feeds the video connector (SK1) on pin 12 (
when driving a SCART TV) and the backplane
expansion socket on pins B31 and B32.
Ensure that the PSU faston power connectors are
securely attached to the main PCB and that the flying
connectors are firmly attached to the drives. if this does
not correct the fault, return the PSU to an Acorn
Authorised CSW for repair.
If the PSU functions for a while before failing, it is likely
that a controlled thermal shutdown has taken place.
This is caused by either a failure of the cooling fan or a
failure of a component that is internal to the PSU.
Switch on and listen for the fan and check that the fan
aperture is not congested or blocked with any debris.
Should the fan fail to run or the PSU continue to shut
down then return the PSU to an Acorn Authorised CSW
for repair.
Action if main PCB fails
Although the main PCB is a replacement only item, there
are some checks that you can make before sending a
faulty PCB to an Acorn Authorised CSW.
Remove the PCB from the main unit, using the
procedure given in Part 2 - Disassembly and assembly
and inspect the board for any of the following:
• ROMs not in correct sockets or pins lifted from
sockets.
• ROM size and type links incorrectly set. See Appendix
F - Main PCB links, plugs & sockets for links LK10,
LK11, LK12 and LK14.
Part 1- Fault diagnosis and repair
• Incorrect location and orientation of any other
socketed devices.
• DRAM size links incorrectly set. See Appendix F Main PCB links, plugs & sockets for links LK23 and
LK24.
• Any loose debris lying on the PCB.
If these checks do not disclose the fault, return the PCB
to an Acorn Authorised CSW for repair.
Action if upgrades fail
RAM Card
To check the RAM card, disassemble the computer
as described in Part 2 - Disassembly and assembly
and check the following:
• The RAM card plug is securely placed in the main
PCB socket.
• The links on the main PCB are set correctly - see
Appendix F - Main PCB links, plugs & sockets for
LK23 and LK24.
• The ZIP ICs are correctly installed in their sockets on
the expansion card.
• The combined amount of DRAM on the RAM card and
the memory size of the main computer is correct:
• 2MB on the main PCB and 1MB or 3MB on the
RAM card is illegal
• 1MB on the main PCB and 2MB on the RAM card
is illegal
• 4MB on the main PCB and any RAM card is illegal
If these checks do not isolate the fault, substitute the
RAM card for a known working RAM card (checking
LK23 and LK24 as you do). Depending on the outcome
of this test, send either the RAM card or the main PCB
to an Acorn Authorised CSW for repair.
Backplane
To test the backplane, you need to run a number of
expansion cards from it. (See the documentation
supplied with the individual Acorn expansion cards for
details). Once you have seen a fault occur on more
than one expansion card, disassemble the unit and
remove the backplane as described in Part 2 Disassembly and assembly. Check that none of the
pins in the plug housing are damaged or bent. Also
inspect the expansion card sockets for damage or
blockage.
If you can detect the fault, refit the backplane making
sure that it is installed securely into the main PCB
socket. Retest the backplane using a known working
expansion card.
If you cannot isolate the fault, substitute a known
working backplane for the existing backplane and
retest. Depending on the result of this test, return either
the backplane or the main PCB to an Acorn Authorised
CSW.
Issue 1, November 1991
1-3
What to do next
Once you have repaired a fault and the computer is
functioning, we recommend that you use the test
software described in the following section entitled
Checking a partly working computer, to check for and
correct any other faults.
Notes:
1 You must only connect the power after you have
made all the other connections.
2 You must switch off the equipment and disconnect
from the mains supply before removing any other
connections.
You will find instructions for removing the top cover in
Part 2 - Disassembly and assembly.
Checking a partly working
computer
Backing up the test disc
The following section gives details of how to isolate
faults to individual modules, using the test disc (0292,
824) on machines which are running, but exhibiting
faults. The test software can be used in two ways:
• As a test suite, including all the tests that you need for
a standard configuration machine. The tests run
automatically and in sequence.
• As individual tests to test an individual module.
We suggest that if the description of a fault is specific to
a module then you only need to run the appropriate
individual test. Once you have determined the area of
the fault and repaired it, make sure that you run the full
test suite on the working computer before returning it to
the customer.
The flowchart on the next page, Figure 1-2: Procedure to
check a partly working computer shows you how to
diagnose and repair a partly working computer.
Before the tests
Before you run the test software suite, you need to
perform the following tasks:
• back up the test disc
• validate the test equipment
• create a test IDE hard disc
• replace the customer's hard disc
• connect the customer's equipment
• save the customer's CMOS RAM settings
• create a CMOS test data file
• check the memory size of the computer
Safety considerations
Some of the tasks described in this section require that
you remove the top cover of the Archimedes computer.
Although the PSU is designed to comply with
BS7002/EN60950 Class 1, you must still take care to
ensure that no metal objects fall (or are put) into the
PSU through the ventilation holes.
1-4
Before you start testing, make a backup copy of the test
disc (0292,824). You will need the following equipment:
• a known working A5000 computer plus keyboard and
monitor.
• test disc to be copied (source disc).
• floppy disc already formatted (destination disc).
Follow the procedure given below to make a backup
copy of the test disc:
1 Start-up the computer so that it displays the desktop.
Note if the desktop is not displayed on start-up type:
*DESKTOP <return>
at the • prompt.
2 Ensure the test floppy disc is write protected, then
insert the test floppy disc into the disc drive.
3 Open the directory window on the floppy disc by
pressing the left hand mouse key while the mouse
pointer is over the floppy disc icon.
4 Execute the ! MakeACopy program by pressing the
left hand mouse key twice while the mouse pointer is
over the !MakeACopy icon in the directory window.
5 You are asked whether you are sure that you want to
back up the test disc. Reply 'y' if the test disc is write
protected.
6 Press the space bar when prompted.
7 Insert the destination disc when prompted.
8 When the program has finished, turn off the monitor
and computer.
Validating the test equipment
Before carrying out any of the tests in this chapter,
validate the test equipment. To do this, follow the
procedures given in this section, substituting a known
working unit for the customer's unit.
If the test equipment fails, you should repair the test
equipment and retest on a known working unit.
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Part 1- Fault diagnosis and repair
issue 1, November 1991
1-5
Creating a test IDE hard disc
To avoid overwriting the customer's hard disc during
testing, prepare a test hard disc. You will need the
following equipment:
• IDE hard disc to be initialised (UUT)
• A5000 test disc (Acorn part number 0292,824)
• A5000 series test station, which is made up of an
A5000 series computer with the hard disc removed
and a keyboard attached (do not use a customer's
computer for this test)
• Standard RGB colour monitor (Analogue RGB) and
cable.
8 From the list that follows, select the option Format
IDE drive 4 by pressing 0. A configuration screen
will then appear which will be followed by the
formatter screen. The disc is then formatted. For
details of the hard disc formatter program, refer to the
information given in the section entitled Hard disc
formatter on page 1-16.
9 When formatting, and initialising is complete, you will
be asked to press the space bar to continue. This
produces the report screen that displays the pass/fail
message.
Notes:
1 Throughout the test procedure make sure that the
power is the last connection made before a test
commences, and the first connection removed when a
test is complete.
10 Press the space bar and, when requested, turn off
the test station.
11 Turn all the mains supplies to the equipment off.
12 Disconnect the UUT, from all associated equipment,
in reverse order to that detailed earlier in this
procedure.
2 The mains supply voltage must be within the rated
voltage range as indicated on the PSU input label.
If any fail messages have occurred, the UUT must be
sent for repair and retested.
3 If a message is expected and has not appeared within
30 seconds then record the fault and repair the
machine. If an error message appears, record the
fault and, if possible, continue the test and then repair
the machine.
The hard disc is now ready to be inserted in the
customer's computer to test the computer system.
4 If the test equipment fails three consecutive UUT's for
the same fault, validate the equipment using a known
good UUT and repair as necessary before continuing
with the test.
The procedure to test an IDE hard disc is given below.
1 Insert the UUT into the test station, taking care to plug
the two cables in correctly. Replace the A5000's top
cover.
2 Connect the test station and the monitor to the mains
supply. Do not turn on.
3 Insert the test disc into the floppy disc drive.
4 Turn on the monitor.
5 Turn on the test station whilst holding down the Delete
key, Shift key and * key (until the auto-boot file is
executed). Use the * key on the numeric keypad not
the * key on shift 8.
6 The following menu is displayed:
MENU VX.XX UN-DEF
(A) Test Suite
(B) Individual Tests
(C) Load / Save CMOS
(D) Quit
Select the test type of your choice
Select the Individual Test option by typing B.
7 The following menu appears on the screen:
Individual Tests
(A) Exp-Cards
(B) Pcb-Module
Select the Pcb-Module option B.
1-6
Replacing the customer's hard disc
WARNING:
IT IS NECESSARY TO REPLACE THE CUSTOMER'S
HARD DISC BEFORE RUNNING THE TEST SUITE, AS
RUNNING THE HARD DISC TESTS MAY DESTROY THE
DATA HELD ON THE DISC.
To ensure that the customer's hard disc is not
overwritten during the test, disconnect the fitted hard
disc and place it in a safe place. Connect and secure
the test IDE hard disc into the computer (see the above
section entitled Creating a test IDE hard disc).
Connecting the customer's equipment
Connect the customer's equipment in the following order:
1 keyboard to front panel connector
2 serial port loopback plug to the RS232 port
3 printer to the video loopback box printer connector
4 headphones to the Headphones 32 Ohm socket
5 parallel to video loopback box between the parallel
port and video socket
6 multi-sync analogue RGB monitor to the parallel to
video loopback box video socket
7 monitor to the mains supply (do not switch on yet)
8 computer to the mains supply (do not switch on yet).
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Saving the customer's CMOS RAM
settings
You need to save the contents of the CMOS RAM before
any of the tests are run, and restore them when the last
test is over, otherwise the settings will be overwritten
This is because the test software uses the CMOS RAM
to control the test sequence and store the results. Follow
the procedure given below to save the customer's
CMOS RAM settings.
1 Insert the test disc (0292,824) into the floppy disc
drive.
2 Hold down the Shift key and switch the computer on (
do not touch the Delete key). Keep the Shift key held
down while the computer powers up.
The following menu will be displayed:
MENU VX.XX UN-DEF
(A) Test Suite
(B) Individual Tests
(C) Load / Save CMOS
(D) Quit
Select the test type of your choice
3 Select option (c) Load / Save CMOS by pressing the
c key.
4 The Load / save CMOS selection will be confirmed
and then the screen will display the following menu:
LOAD / SAVE CMOS RAM VX.XX UN-DEF
1. Save CMOS RAM to disc.
2. Load CMOS RAM from disc.
3. Exit Program.
Please select the required option ?
5 Select option 1, and then replace the test floppy disc
with the data disc.
6 When prompted, enter the filename (including the full
directory path if necessary) that you want the CMOS
RAM saved to.
7 Remove the data disc and put it in a safe place.
8 Press the space bar to continue.
9 Type 3 to exit the program.
10 Switch off the computer (leave the monitor on).
3 Switch on the computer, whilst holding down the
Delete key (not the backspace key), the Shift key and
the * key on the numeric keypad. Keep holding down
these keys for several seconds, until the auto-boot file
is executed. (This action clears the CMOS RAM and
resets the configuration defaults to the manufacturer's
original specification).
4 A boot file now runs and displays the following menu:
MENU VX.XX UN-DEF
(A)
(B)
(C)
(D)
Test Suite
Individual Tests
Load / Save CMOS
Quit
Select the test type of your choice
5 Select the Load / save CMOS option from the menu.
6 Select the save CMOS to disc option.
7 When prompted, enter the path and file name where
you want the default CMOS RAM settings saved.
8 Store this test data file on a separate disc (the CMOS
RAM test data disc).
9 Remove the test data disc and put it in a safe place.
10 Press the space bar to continue.
11 Type 3 to exit the program.
12 Switch off the computer (leave the monitor on).
You have now created a new CMOS RAM test data file.
Checking the memory size
You should check the amount of memory that is fitted to
the computer and make a note of the size as you will be
asked to choose the computer configuration in the test
suite. Each computer will have either 1 or 2 MB on the
main PCB and either 1, 2, or 3 on the memory
expansion card if any are fitted.
To find out the memory size of the computer either ask
the customer or remove the top cover as described in
Part 2 - Disassembly and assembly and check how
much memory there is in the machine.
Creating a CMOS test data file
If you intend to run the full test suite or the CMOS RAM
test (see the section entitled Battery backed RAM test on
page 1-9) you need to create a CMOS test data file to
save the manufacturer's default settings. Note that
before you do this you must save the customer's CMOS
RAM settings as described in the previous section.
To create a CMOS test data file, proceed as follows:
1 Switch off the computer (leave the monitor on).
2 Insert the test disc (0292,824) into the floppy disc
drive of the customer's computer.
Part 1- Fault diagnosis and repair
issue 1, November 1991
1-7
Running the functional tests
About the tests
The test disc (0292,824) contains various menu-driven
tests. The menus are generated from a set of text files.
(You can generate new text files if you wish).
There are two types of test:
• subjective — you must judge whether the equipment
passes or fails these tests. For this reason it is a good
idea for you to familiarise yourself with the correct
results given by a known good computer (see the
section entitled Validating the test equipment on page
1-4). In this way you will be in a better position to
judge faulty results.
• non-subjective — the test program passes or fails the
equipment.
How to operate the test software
The tests are menu-driven, so the menu option that you
select determines the test to be executed. To select an
option, type the corresponding letter. Some menu
options lead to further options, other options run tests
immediately.
During the test sequence, the software runs through
each individual test and then prompts you to press the
space bar:
PRESS <SPACE BAR> TO CONTINUE
If the computer passes the current test, the test program
waits for approximately 1 second and, if you do not
press the space bar in this time, continues with the next
test. If you do press the space bar within the 1 second
period, the program continues immediately.
If the computer fails the current test, the test program
bleeps and waits for you to press the space bar. This
allows you to make a note of the fault and then continue
with the tests. You should also note any other failures,
but bear in mind the possibility that these failures could
be caused by the first recorded failure.
If an expected message has not appeared on the screen
within 30 seconds, you must record the fault, switch off
the machine and repair before retesting.
Repairing faults
When repairing a computer, you should repair the faults
in the order in which they occurred during the test (i.e.
repair the first recorded failure first).
1-8
The following is an example of how to test a standard
computer.
Note: In order to run the functional tests you must
first have saved the customer's and manufacturer's
CMOS RAM settings, as described in the previous
sections.
1 Insert the test disc (0292,824) into the floppy disc
drive.
2 Switch on the computer, whilst holding down the
Delete key (not the backspace key), the Shift key
and the " key on the numeric keypad. Keep holding
down these keys for several seconds, until the autoboot file is executed. (This action clears the CMOS
RAM and resets the configuration defaults to the
manufacturer's original specification).
3 A boot file now runs and displays the following menu:
MENU VX.XX UN-DEF
(A)
(B)
(C)
(D)
Test Suite
Individual Tests
Load / Save CMOS
Quit
Select the test type of your choice
4 To run the entire test suite, select option A from the
above menu. To run an individual test, select option B
from the menu and select the appropriate test. Refer
to the section entitled Additional individual tests on
page 1-16 for details of the individual test menus and
then read the description of the test in the following
sections. The instructions below refer to the full
functional test suite.
5 If you selected option A, select the A5000 option
from the next menu which will configure the CMOS
RAM for the selected computer. The computer
displays a list of choices:
(A)
(B)
(C)
(D)
A5000
A5000
A5000
A5000
1Mb
1Mb
2Mb
2Mb
Fun.
Soak
+ HD
+ HD
Test
Test
Fun. Test
Soak Test
Press * to quit - for top menu
Select the functional test that is correct for the
memory configuration of the machine.
6 A list of settings will then appear on the screen. These
are the test configuration modules read from the test
data file and set up in the CMOS.
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Action if the battery backed RAM test fails
Memory test
The screen will clear and the following menu is displayed:
MEMORY TEST VX.XX DEALER
Amount of Memory 2 Mbytes
Running four phase memory test.
Lower memory limit &000088BC
Upper memory limit &00141EA0
Phase one : incrementing pattern....
Phase two : Cycling bits..............
Phase three : TRUE Hierarchy..........
Phase four : FALSE Hierarchy..........
PASSED.....
PRESS <SPACE BAR> to continue
You should check that the amount of memory displayed
is the same as that you made a note of at the end of the
section entitled Checking the memory size on page 1-7.
Note: The upper and lower memory limit can vary
slightly between releases of the test software, hence
approximate values are given.
Action if the memory test fails
If the test fails, refer to the sections entitled Action if
main PCB fails and Action if upgrades fail on page 1-3.
Battery backed RAM test
The test continues by testing the battery backed RAM.
The following is displayed on the screen:
CMOS TEST VX.XX DEALER
Copied
Passed
Passed
Copied
Passed
CMOS
CMOS
Read
CMOS
CMOS
RAM into main memory.
RAM Configuration.
- Write function.
RAM from main memory.
RAM Verification Test
THIS SUB TEST HAS PASSED
PRESS <SPACE BAR> TO CONTINUE
During the Read - Write function test of the CMOS RAM
you will be requested to enter the file name for the
CMOS data file that should be used for this test. This file
contains some of the CMOS data, and will change with
different configurations of unit (i.e. IDE fitted etc). You
should press Return to use the default data file. If you
need to use a specific file, not the default, then enter the
path and filename of the data file to be used (this is the
one you created in the section entitled Creating a CMOS
test data file on page 1-7).
Part 1- Fault diagnosis and repair
Check that the CMOS test data file is correct (see the
section entitled Creating a CMOS test data file on page
1-7). if the test still fails, then refer to the section entitled
Action if main PCB fails on page 1-3.
Note: if this test fails you cannot rely on the results of
the remaining tests. This is because the CMOS RAM is
used to control the test sequence and store the results.
IDE hard disc drive interface test
The screen will clear and the following will be displayed:
IDE INTERFACE TEST VX.XX DEALER
Drive 4 is IDE
ADFS::4 is IDE drive 0
IDE drive : 0
Description : <aaaaa> <bbbbb>
Firmware version : <cccc>
PASSED byte check
THIS SUB-TEST HAS PASSED
PRESS <SPACE BAR> to continue.
Note:
<aaaaa> Drive manufactures name (e.g.
Conner Peripherals)
<bbbbb> Drive model number (e.g. CP3044)
<ccccc> Firmware version number (e.g. 2SA4.53)
Note that during the soak test the IDE drive interface
test is not executed (see the section entitled Performing
soak tests on page 1-17).
Action if the IDE hard disc drive fails
Check that the machine configuration is set for "
IDEdiscs 1" and reset if necessary. Disassemble the
computer using the procedure given in Part 2 Disassembly and assembly and check the following:
• the 40 way data cable is securely connected to the
drive and to PL9 on the main PCB.
• the 4 way power connector is correctly attached.
Try substituting a known working data cable for the
existing cable and retest.
Using a voltmeter confirm that the following voltages
appear on the 4 way power connector:
• OV on pins 2 and 3 (black cable)
• 5V on pin 4 (red cable)
• +12V on pin 1 (yellow cable)
If a voltage is missing, check the crimps within the,
connector shell and repair if possible. If the problem is
within the PSU then you must return this to an Acorn
Authorised CSW.
Issue 1, November 1991
1-9
External port tests
Hardware check
The test continues by running a comparison check
between the test data file and that which is fitted to the
computer. The screen will clear and the following will be
displayed:
COMPUTER TYPE TEST VX.XX DEALER
PASSED CPU version matches
PASSED MEMC version matches
PASSED OS version matches
PASSED Memory size matches
PASSED ST506 int. correct setup
PASSED ST506 ext. correct setup
PASSED IDE int. correct setup
PASSED Hard disc is correct size
PASSED FDC correct setup
PASSED Serial correct setup
PASSED Ethernet I correct setup
PASSED Ethernet II correct setup
PASSED SCSI Podule correct setup
PASSED ROM Podule correct setup
PRESS <SPACE BAR> TO CONTINUE
If the test fails, make a note of the fault and press the
space bar.
The following will be displayed:
COMPUTER TYPE TEST VX.XX DEALER
PASSED
PASSED
PASSED
PASSED
UPM correct setup
I/O correct setup
I/O MIDI correct setup
MIDI correct setup
PRESS <SPACE BAR> TO CONTINUE
Action If hardware check falls
Check that the system matches the data file that you
selected. A guide to the test data file can be to read the
system variables that start:
Test_xxxx :y.
Test_Serial_port : 1 serial port
fitted.
If a module is fitted, the related test system variable
should exist, the hardware check verifies this. If it is a
version number check, then the hardware check
compares the version number with the version fitted. The
value attached to the string is only used in this test when
checking version numbers or memory size. If the value is
non-zero, it means the test is to be executed.
Test_MEMC_Version : 101 MEMC version
la fitted
If the data file is correct, refer to the section entitled
Action if main PCB fails on page 1-3.
1-10
You should be familiar with the correct print-out pattern
before running this test. It should resemble Figure 1-3:
Printer test output shown overleaf.
While each test is being run the word Running
will appear next to the test and then, when the test
is complete, the pass/fail message will overwrite it.
The Printer test sends a test pattern to the printer. The
pattern comprises a repeated series of stepped lines,
each representing bits 0 to 7. You should look for a
missing or corrupted pattern. As this is a subjective test
make a note of any faults that you detect.
The RS423 port test is carried out automatically and
gives a passed/failed message.
The screen will clear and the following will be displayed:
EXTERNAL PORTS TESTS VX.XX DEALER
Passed
Passed
Passed
Passed
Passed
Passed
PRINTER,EPSON FX.
Printer Graphic Test.
Printer Text Test.
SERIAL, 82C710 CHIP TEST.
Control Line Test.
Data Line Test.
Passed Communications State Test.
Passed Baud Rate Test. NOT DOING
ECONET PORT TEST
THIS SUB-TEST HAS PASSED
PRESS <SPACE BAR> TO CONTINUE
Check the printout.
Action if printer test fails
• Check that the configuration settings for PRINTER
and IGNORE are correct.
• Check that the type of printer displayed matches the
type used.
• Check that the printer is on line and that the printer
lead is connected correctly and functions correctly.
• If the fault still persists then refer to the section entitled
Action if main PCB fails on page 1-3.
Action if the RS423 tests fail
• Ensure that the configuration items BAUD and DATA
are set to sensible values (see the RISC OS User
Guide).
• If the test still fails, check that the correct loopback
plug is fitted and that it functions correctly (this can
be done by trying it on another unit).
• If the unit still fails, then refer to the section entitled
Action if main PCB fails on page 1-3.
Note: During the soak tests neither the printer nor the
RS423 tests are executed (see the section entitled
Performing soak tests on page 1-17).
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Figure 1-3: Printer test
Action if floppy disc drive fails
Disc interface test
The screen will clear and the following will be displayed:
FLOPPY DISC TEST VX.XX DEALER
Passed Write Protect Test.
Passed Verification Test.
Running Write Track Test 0, Drive 0
Remove the test disc from drive :0
Insert the BLANK DISC in drive :0
The BLANK DISC needs to be F Map
Insert the blank scratch disc, and the write track test
continues, displaying the following on the screen:
Working Track 76 Sector 04 Head 00
Disc Address used &000BF000
The read track and erase track tests are now complete.
When you are requested, put the test disc back in drive
:0. Press the space bar to continue.
If the write protect test fails it will corrupt the test disc.
You will then have to replace it with a new copy. A sign
of this corruption is that a file called ! DISC_FAIL will
appear on the disc, and the disc will not boot.
If errors occur during the read test, a maximum of 12
read errors may occur per sector before the next sector
is read. A total of 6 sectors are tested.
Note: During the soak tests only the write protect and
verification tests are executed (see the section entitled
Performing soak tests on page 1-17).
Part 1- Fault diagnosis and repair
If there is no desktop icon, check the CMOS RAM
configuration for "floppies 1" and reset if necessary.
Disassemble the machine (see Part 2 - Disassembly
and assembly) and check that both the 34 way data
cable and the 4 way power cable are securely
connected at the rear of the drive. Also check that the
data cable is connected to the main PCB at PL10.
Using a voltameter, check that OV and +5V are present
on the drive power cable and OV on pins 2 and 3, +5V
on pin 1 (conductor 1 is marked with white on the
cable). If there is no power, inspect the crimps inside
the connector shell and repair or replace if possible. If
the failure is with the PSU itself, return it to an Acorn
Authorised CSW for repair.
Check the data cable by substituting a known working
cable and retesting.
Check that IC38 is located securely in its socket.
As a final measure, try substituting a known working
floppy disc drive. Depending on the outcome of this
test, return either the main PCB or the floppy drive to
an Acorn Authorised CSW for repair.
IIf an icon is present but an error occurs during
access, disassemble the machine and check that the
34 way data cable is correctly connected both at the
rear of the drive and on the main PCB PL10.
Check the data cable by substituting a known working
cable.
Issue 1, November 1991
1-11
Also check that the main PCB links are set correctly.
See Appendix F - Main PCB links, plugs & sockets for
LK18, LK19 and LK21.
Try to format a new floppy disc and retest the drive by
attempting to read the original disc on another machine.
Note that if this fails the disc may be corrupted.
As a final measure, try substituting a known working
floppy disc drive. Depending on the outcome of this test,
return either the main PCB or the drive to an Authorised
Acorn CSW for repair.
1 Listen to the sequence of notes.
2 Check for any deviation from the known good sound,
and ensure that a clean sound is being emitted from
both channels.
3 Listen for any interference or background hissing from
the speaker.
Press F5 if correct, or F8 if not correct, to continue. You
cannot press a function key until at least one cycle of
each sound channel is complete. If the test fails, refer to
the following section entitled Action if audio tests fail.
Headphone tests
Real time test
The screen will clear and the following menu will be
displayed:
TIME TEST VX.XX DEALER
1) CHECK THE DATE AND TIME
2) SET THE DATE AND TIME
3) CHECK THEN SET THE DATE AND TIME
Please select the required option ?
The normal procedure is to select option 1. If you want to
reset the time or date you would select 2 or 3. For
example, you can:
• type 1 to check the date and time
• check that the time is correct and the seconds are
incrementing correctly.
Then either press F5 (if correct) or F8 (if not correct),
and press the space bar to continue.
Action if real time test falls
If the test fails, refer to the section entitled Action if main
PCB fails on page 1-3.
Audio tests
Note that the audio tests are subjective tests and that
you should be familiar with the correct sounds before
running the tests.
Speaker tests
The screen clears and the following menu is displayed:
The screen will then clear and the sound test results will
be displayed. If the test fails, refer to the following
section entitled Action if audio tests fail.
Action if audio tests fail
If it appears that the speaker alone is at fault, check the
speaker connections. Ensure that the cable connecting
the speaker to the PCB is in place. Also check the
solder joints on the speaker tags and the two crimps in
the shell. Repair any bad joints and try the tests again.
For details of how to remove the speaker, refer to Part 2
-Disassembly and assembly.
If the headphones alone appear at fault, substitute a
known working pair of headphones and retest.
Also check that the CMOS RAM configuration has not
been set to mute the speaker and that the audio volume
is set to an appropriate value.
If these actions fail to restore the audio system or the
audio system is distorted or corrupted in some way, you
must remove the main PCB and return it to an Acorn
Authorised CSW.
Video tests
The display tests are subjective tests and you should be
familiar with the correct screen displays before running
these tests and make a note of any failures.
SOUND TEST VX.XX DEALER
Running Loudspeaker Test
Listen and check sound quality
Stereo Output Channel
Flashing arrow heads (««) will then point alternately left
and right depending on the stereo channel being used.
The test consists of a repeating sequence of 8 musical
notes.
1-12
The headphone test is similar to the speaker test except
that the sound is sent through the headphones. The
same checks that are used for the loudspeaker test
should be undertaken. The first four notes are played in
one headphone and the next four notes in the other
headphone.
The screen will clear and the following will be displayed:
VIDEO TEST VX.XX DEALER
Running Standard Colour Tests
PRESS <SPACE BAR> to continue.
These tests consist of a series of screen displays. You
proceed through the tests at your own pace. When you
press the space bar the screen test will commence.
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Action if video tests fail
Standard colour test
The screen test displays four colour bars red, green,
blue and grey scale. Each colour bar is divided into 6
sections. The number at the top of the screen is the
value sent to the individual colour gun. Only one gun is
driven at a time for the red, green, and blue bars. The
grey scale bar is produced by equal amounts driving
each of the colour guns.
Starting from the left, the first block is no units of colour,
the next block contains a small amount of red (1 unit bit
0 set) the next more red (2 units - bit 1 set) continuing
along until the block is a full red (15 units of red - all bits
set).
The left most three blocks are out-lined with rectangles
of full colour. Check that the colour increases with each
block, to full intensity on the right most block. This
should be true for each colour bar.
The background is divided into two triangles; one brown
and one grey/blue colour. Check the linearity of the
dividing line and the colour of the triangles. A cursor is
made up of three squares and passes across the screen
from bottom left to top right. Also verify that the cursor
contains three rectangular outlines in colours green, blue
and red. Check the linearity of movement and also check
the transparency of the cursor as it moves across the
screen. Make sure that the colours do not change as the
cursor moves across the screen. Verify the border
colour.
If there is no display check that there is power on the
monitor (green LED on) and that the brightness and
contrast controls are sufficiently advanced. If a video
cable adaptor is in use then make sure this corresponds
to one of the types described in Appendix E - Monitor
adaptor cables.
Check that the video loopback is functioning correctly by
making sure that it works on a known working machine.
Switch the machine off, hold down the key marked "." on
the numeric keypad and switch the machine on holding
down this key for at least a further 10 seconds. This has
the effect of resetting the monitor configuration to match
the type of monitor connected. If this fails to solve the
problem then substitute a known good monitor and
cable and try again.
If this action still fails to produce a display, remove the
top cover of the computer (see Part 2 - Disassembly
and assembly) and check on the main PCB that the
shunts on LK6 pins 1 and 2 and LK6 pins 3 and 4 have
not been dislodged. As a final action, remove the main
PCB and return it to an Acorn Authorised CSW for
repair.
Press F5 if the display is correct, or press F8 if not.
If the test fails, refer to the following section entitled
Action if video tests fail.
If the display is corrupted, check the adaptor cable (if
used) against those listed in Appendix E - Monitor
adaptor cables and reset the monitor configuration via
the power up "." process. Check the monitor and cable
by substituting with known working items and repeat the
power up "." process. If the fault proves to be with the
main computer then you must return the main PCB to
an Acorn Authorised CSW for repair.
High resolution monochrome display
Video configuration test
This test is not done.
Press the space bar to continue.
Standard VGA display
The same display is used in a VGA mode as in the
standard colour test. Repeat all the checks that were
performed on the standard monitor test on the standard
VGA display.
Note that the border is removed in the standard VGA
tests.
Press F5 if the display is correct, or press F8 if not. If the
test fails, refer to the following section entitled Action if
video tests fail.
Super VGA display
You are presented with a screen display that contains 16
squares, made from shades of red, green, blue and
grey. Check that the image is sharp, clear and stable on
the screen.
Note that the border is removed in Super VGA tests.
Press F5 if the display is correct, or press F8 if not. If the
test fails, refer to the following section entitled Action if
video tests fail.
Part 1- Fault diagnosis and repair
A pass/fail message is displayed after testing the video
configuration circuitry.
This test will write data to the video loopback box via the
printer port which will simulate different monitor types at
the video socket. The monitor configuration is then
checked.
Action if video configuration test fails
If the test fails, check that the correct data is being sent
from the printer port by connecting the printer.
If the printer functions correctly, check that the monitor
loopback box is working by replacing the box and
cables.
If the video configuration test still fails with a known
working printer port and monitor loopback box, return
the main PCB to an Acorn Authorised CSW for repair.
Summary screen
At the end of the screen tests a final summary screen
will be displayed.
Press the space bar to continue.
Issue 1, November 1991
1-13
Keyboard and mouse tests
Note that for the mouse test you will need a mouse jig
template to perform the test (see Appendix A - Mouse
test jig template).
Reset button sub-test
During this test you are asked to press the Reset button
to test the operation of the switch. If this button works,
the program moves onto the next sub-test automatically.
If the test fails, refer to the section entitled Action if
keyboard fails on page 1-15.
Stuck key sub-test
This sub-test tests for stuck keys or mouse buttons. If no
items are found to be stuck, the test software moves
onto the next test automatically without displaying any
information.
If any keys or mouse buttons are stuck down, you will
see the following screen display:
SOME KEYS ARE STUCK
Note the keys that are stuck, reject the
keyboard or the mouse.
Press the Break key to continue and wait.
Press the Break key and the program moves to the
Keyboard/Mouse report screen. Refer to the section
entitled Action if keyboard fails on page 1-15.
3 The screen is then cleared, and a rectangle is drawn
in the bottom left hand corner with the word Left
printed inside it. Do not move the mouse at this stage.
4 Press the left hand mouse key.
5 The screen will then clear, and you should move the
mouse to the bottom right hand position on the test jig.
Ensure the mouse does not skid on the jig as you
move it.
6 As the mouse moves across the jig, a box will appear
in the bottom right hand corner of the screen. When
the mouse reaches the bottom right hand position on
the jig, the pointer on the screen should be in the
centre of the displayed box.
7 Press the right mouse button, when requested. A new
box now appears in the top right hand corner.
8 Move the mouse to the top right hand position on the
test jig. Again the screen pointer should appear in the
centre of the displayed box when the mouse is in the
top right hand position on the test jig.
9 Press the requested key.
10 Repeat this exercise for the two remaining positions.
• If the pointer does not finish in the displayed box
when the mouse is in the relevant test jig box, the
test has failed.
•
Break and Escape key stuck sub-test
•
If the Break or Escape keys are stuck down, you will see
the following message on the screen:
•
This sub-test tests if the Break or Escape keys are stuck
down. If the keys are not stuck, the test software moves
onto the next test automatically without displaying any
information.
THE ESCAPE OR BREAK KEYS ARE STUCK
DOWN. REPLACE THE KEYBOARD
If you press the wrong mouse button and the
pointer is not in the rectangle, then nothing will
happen.
If you accidentally press two buttons together, you
will see both buttons displayed on the screen. The
screen is displayed in inverse video and the
depressed keys are displayed on the screen.
Press the Break key to continue the test.
If you cannot make a button disappear then it will
be impossible to continue the test.
Refer to the section entitled Action if keyboard fails on
page 1-15.
If the test fails, refer to the following section Action if
mouse falls.
If the mouse if functioning correctly, the program moves
on to the next test.
Mouse sub-test
Action if mouse fails
This tests the three buttons on the mouse and the
movement of the mouse to the left, right, up and down.
Each of the mouse buttons (i.e. left, middle, right) are
displayed on the screen in turn, together with a pointer.
You need a mouse test jig template to perform this test.
See Appendix A - Mouse test jig template.
During this test the mouse is viewed with the cable
coming out of the top of the mouse. Take care to ensure
that the mouse does not 'skid' on the template when you
move it.
1 The test starts by clearing the screen and asking you
to position the mouse in the bottom left hand corner of
the mouse test jig.
2 With the mouse in this position, press the middle key.
1-14
Check that you are testing the correct mouse type by
reading the data file, or by referring to the keyboard
main menu screen. Ensure that the configuration setting
for MouseStep (0) is correct.
If, when you pressed the requested mouse button,
nothing happens or the program repeatedly claims that
two keys were pressed or the pointer will not move, then
substitute a known working mouse of the same type and
retest. This determines if the fault is within the mouse
itself or the keyboard's mouse interface. If the fault is
within the keyboard, refer to the section section entitled
Action if keyboard fails on page 1-15.
Check that roller ball is not sticking, in which case you
can remove and clean it. If the mouse still fails then
return it to an Acorn Authorised CSW for repair.
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Main keyboard sub-test
3 This test is repeated for the remaining two keyboard
LEDs, the display giving you suitable prompts. Note
any LED failures before continuing with the next test.
This is a subjective test. If the test fails, refer to the
following section entitled Action if keyboard fails.
Main Keyboard Test
Press each key in turn, starting at the bottom left (Caps
lock) moving across to the bottom right (Ctrl) key, then
up a line to the left hand Shift key.
Keyboard/mouse report screen
For this sub-test, the display clears and the main
keyboard matrix is displayed with the following title at the
top of the screen:
As you move across the keyboard pressing the keys in
the correct order, the key that is pressed should
disappear from the display. The test continues in this
way until all the keys up to the function key F12 have
been tested.
If you press the wrong key nothing will happen. If you
press two keys (the correct key and one other) the
screen is shown in inverse video and the depressed
keys are shown on the screen. If a key fails to disappear
after three attempts, the program displays a failure
message at the top of the screen and then prompts you
to press the Break key. The program then exits to the
Keyboard/ Mouse report screen. Refer to the section
entitled Action if keyboard fails on page 1-15.
If the keyboard functions correctly, the program moves
onto the next test.
Numeric keypad sub-test
For the numeric keypad sub-test, the display clears and
the cursor and numeric key matrixes are displayed on
the screen. The two key matrixes are tested separately:
first the cursor keys, then the text editing keys, and then
the Print, Scroll Lock and Break keys.
Finally the numeric matrix is tested, starting with the 0
key and working along the matrix in the same pattern as
before, finishing with the # key.
If you press the wrong key, nothing will happen. If you
press two keys, this is highlighted in inverse video. If a
key fails to disappear after three attempts, the program
displays a failure message at the top of the screen, and
then prompts you to press the Break key. The program
then exits to the Keyboard/ Mouse report screen. Refer
to the section entitled Action if keyboard falls on page 115.
If the keyboard functions correctly, the program moves
onto the next test.
Keyboard LED sub-test
This test checks that the LEDs on Caps Lock, Scroll
Lock and Num Lock are working.
The screen clears and the following is displayed:
Running Keyboard LED Tests
CHECK <CAPS LOCK> LED IS ON
1 Check that the caps lock keyboard LED is the only
LED on, the other two are extinguished.
At the end of a successful test the following screen
is displayed:
KEYBOARD & MOUSE TEST VX.XX DEALER
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
Logitec Mouse
Reset Button
Stuck Keys
Keyboard LED
Main keyboard
Numeric Keypad
Test
Test
Test
Test
Test
Test
PASSED MOUSE
TEST
PASSED KEYBOARD
TEST
THIS SUB_TEST HAS PASSED
PRESS <SPACE BAR> TO CONTINUE
The message that the keyboard has passed the sub-test
refers only to the non-subjective test elements and
should not be interpreted as an overall pass, since you
may wish to fail the UUT on a subjective test element.
Note: During the soak test neither the keyboard nor the
mouse tests are executed (see the section entitled
Performing soak tests on page 1-17).
Action if keyboard fails
Substitute the existing keyboard for a known working
keyboard and retest.
If the fault lies with the original keyboard, disassemble
the keyboard unit (see Part 2 - Disassembly and
assembly) and inspect the keyboard PCB for damage,
loose sockets, stuck keys etc. If you cannot find any
obvious fault, return the keyboard PCB (not the entire
keyboard) to an Acorn Authorised CSW for repair.
If the working keyboard fails, disassemble the computer
case (see Part 2 - Disassembly and assembly) and
inspect the main PCB for the correct positioning of the
following shunts:
• LK1 shunt between pins 1 and 2
• LK2 shunt between pins 1 and 2
• LK4 shunt between pins 1 and 2
• LK5 shunt between pins 2 and 3
If these are correct then remove the main system PCB
and return it to an Acorn Authorised CSW for repair.
2 Press F5 to PASS or F8 to FAIL the test (do this for
each subsequent LED test). Check the caps lock is
extinguished, hence all keyboard LEDs are off.
Part 1- Fault diagnosis and repair
Issue 1, November 1991
1-15
Test report
At the end of this sequence of tests, a report screen
shows the status of the tests.
REPORTS VX.XX DEALER
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
PASSED
Hardware Check
Memory Test
Floppy Disc Test
Keyboard Test
CMOS RAM Test
Time Test
Mouse Test
Parallel Port Test
Serial Port Test
Sound Test
Video Test
IDE Interface Test
Select the Hard Disc Exerciser option from the list
of individual tests. This program exercises the hard disc
by creating 20 random data files on the disc. It then
performs various operations on these files. A pass
completion screen is displayed, similar to that shown
below:
SCSI WINCHESTER EXERCISER
Operations 4000
Pass
TESTS PASSED : 1 Loop completed
PRESS <SPACE BAR> TO CONTINUE
A list of the test pass/fail results are displayed, allowing
you to note any failures. If any failures occurred, repair
the UUT if possible and start the test procedure again.
The hard disc (if fitted) is parked ready for the UUT to be
powered down.
If you would like to perform additional individual tests on
the unit, such as the hard disc exerciser and hard disc
reformatter, refer to the following section entitled
Additional individual tests. Otherwise go to the section
entitled After the tests on page 1-17.
Additional individual tests
You can also access the following individual tests from
the main test menu:
• expansion card tests
• PCB module tests
Note: The expansion card tests are not described in this
manual but are documented separately in the notes
accompanying each individual expansion card.
Select option B from the main test menu:
MENU VX.XX UN-DEF
(A) Test Suite
(B) Individual Tests
(C) Load / Save CMOS
(D) Quit
Select the test type of your choice
You will see the following menu displayed on the screen:
Individual Tests
(A) Exp-Cards
(B) Pcb-Module
Select option B for a full list of the available individual
tests. The hard disc exerciser and hard disc formatter are
included in this list and are described in the following
sections.
1-16
Hard disc exerciser
File
File
File
File
File
File
File
File
File
File
Disc
Fail
1
104
File B
2
98
File C
3
166
File D
4
157
File E
5
86
File F
6
48
File 10
7
98
File 11
8
80
File 12
9
112
File 14
A
85
File 15
Op. : 0 Commands : 0
Pass Fail
57
70
75
89
77
98
181
103
93
114
The values given to Disc Op. and commands are 8 bit
patterns decoded to be the following:
Disc Op.
Bit 7,6,5
Bit 4
Bit 3
Bit 2
Commands
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Not used
Read Failure
Write Failure
Failed trying to close file
Fail try to load dummy file
Compact Failed
Verify Failed
Free Failed
Map Failed
CAT Failed
not used
not used
If you have finished testing, follow the instructions in the
section entitled After the tests on page 1-17. If you would
like to format the IDE hard disc, follow the procedure
given in the next section.
Hard disc formatter
WARNING:
THIS TEST WILL WRITE TO THE IDE HARD DISC. YOU
SHOULD FIT A TEST HARD DISC (SEE THE SECTION
Creating a test IDE hard disc ON PAGE 1-6) OR ALTERNATIVELY ENSURE THAT THE CUSTOMER IS AWARE
THAT THEIR HARD DISC WILL BE OVERWRITTEN, AND!
HAS GIVEN THEIR CONSENT BEFORE YOU START.
Select the Hard Disc Formatter option from the
menu which lists the individual tests. Note that the figures
given in the following example are for illustration only and
vary according to the model of hard disc drive.
Issue 1, November 1991
Part 1- Fault diagnosis and repair
When you run the hard disc formatter program, the
screen clears and the following information is displayed
(the figures given are typical for a 40MB hard disc):
HARD DISC FORMATTER
Format which drive (4-7)? 4
Drive 4 is an IDE drive
IDE drive ADFS:4 identifies itself as :
Description
: <manufacturer's name,
model no.>
Firmware Version : <Version no.>
Configuration
: < ? cyclinders, ?
heads and ? sectors/track>
This disc was last formatted using
the standard shape :
<manufacturer's name, model no.>
526 Cylinders, 4 Heads and 40
Sectors/Track
Parking cylinder 527, Initialisation
flag 1
Do you wish to use this shape (Y/N) ?
N Do you wish to use the standard shape
for this drive (Y/N) ? Y
A: no more changes
B: add defect by cylinder, head,
byte/sector
C: add defect by disc address
D: remove defect
A,B,C, or D ? A
Disc will be formatted as
<manufacturer's name, model
no.> 526 Cylinders, 4 Heads and 40
Sectors/Track
Parking cylinder 527, Initialisation
flag 1
Format or just initialise the drive
(F/I) ? I
Soak test the hard disc for defects
(Long/Short/None) ? S
Are you SURE you want to do this to
drive ADFS:4 (Y/N) ? Y
Verifying
Large file allocation unit?
512 Writing defect list
Creating map
Writing map
Writing root directory
Bytes free &02910800 = 43059200
Bytes Used &00007800 = 30720
PRESS <SPACE BAR> TO CONTINUE
After the tests
At the end of the functional test suite, we recommend
that you:
• perform the soak tests
• perform the safety tests
• retest the unit
Part 1- Fault diagnosis and repair
See Figure 1-4: Procedure after repair overleaf for an
overview of this procedure.
Also, before returning the computer to the customer, you
must perform the following tasks using the procedures
described in this section:
• restore the CMOS RAM settings
• replace the customer's hard disc (if necessary)
• switch off the equipment
• disconnect the equipment
Performing soak tests
At the end of the test suite or individual test, we
recommend that you carry out a soak test on the UUT.
Once the soak test has finished, it is advisable to run the
full sequence of tests on the computer again before
returning it to the customer.
To perform a soak test, leave the unit under test
powered up for eight hours, or alternatively, overnight.
To run the soak tests, select option A from the main test
menu.
MENU VX.XX UN-DEF
(A) Test Suite
(B) Individual Tests
(C) Load / Save CMOS
(D) Quit
Select the test type of your choice
Select the 'A5000' option from the next menu and the
computer displays the following list of choices:
(A) A5000 1Mb Fun. Test
(B) A5000 1Mb Soak Test
(C) A5000 2Mb + HD Fun. Test
(D) A5000 2Mb + HD Soak Test
Press * to quit - for top menu
Select the soak test option that is correct for the
configuration of the machine.
Performing safety tests
Once you have proved that the UUT functions correctly,
you must perform the safety tests described in Appendix
C - Earth continuity testing and Appendix D - DC
insulation testing - class 1.
If either the earth continuity test or the DC insulation test
fails, take steps to fix the fault. if the problem lies with
the PSU, return it to an Acorn Authorised CSW for
repair.
Retesting the unit
On successful completion of the soak test, we
recommend that you retest the computer using the full
functional test suite.
Issue 1, November 1991
1-17
Figure 1-4: Procedure after repair
1-18
Issue 1, November 1991
Part 1- Fault diagnosis and repair
Restoring the CMOS RAM settings
When you have finished testing, you need to restore the
customer's original CMOS RAM settings:
1 Press the Shift and Break keys simultaneously. This
produces the top level menu:
MENU VX.XX UN-DEF
(A) Test Suite
(B) Individual Tests
(C) Load / Save CMOS
(D) Quit
Select the test type of your choice
2 Select option (C) Load / Save CMOS. This
produces the following menu:
LOAD / SAVE CMOS RAM VX.XX UN-DEF
1. Save CMOS RAM to disc.
2. Load CMOS RAM from disc.
3. Exit Program.
Please select the required option ?
3 Select option 2, and replace the test disc in the
floppy drive with the data disc which holds the stored
CMOS RAM settings.
4 When prompted, enter the filename (including the full
directory path if necessary) that contains the
customer's CMOS RAM configuration settings. Press
Return.
2 Switch off the power to the computer (at the mains
switch on the front of the machine).
3 Switch off the power to the rest of the equipment.
Disconnecting the equipment
It is important to disconnect the equipment from the
computer in the correct order:
1 Disconnect the Archimedes computer from the mains
supply.
2 Disconnect all monitors from the mains supply.
3 Disconnect all other equipment from the mains
supply.
4 Disconnect all monitors from the Archimedes
computer.
5 Disconnect the headphones from the headphones
socket.
6 Disconnect the printer from the Parallel Printer port.
7 Disconnect the serial port loopback plug from the
RS423 socket.
8 Disconnect the keyboard from the front panel
connector.
9 Disconnect all other test equipment from the
computer.
Packing
5 Remove the data disc when prompted.
6 Press the space bar to continue.
7 Type 3 to exit the program.
After servicing, repack the computer in its box. To avoid
damage, do not send the computer through the post or
by courier unless it is in its original packaging.
Replacing the customer's hard disc
If you created and fitted a test IDE hard disc, you need
to replace it with the customer's original hard disc. To do
this follow the instructions given below:
1 Replace the test hard disc with the original hard disc,
using the procedure given in Part 2 - Disassembly and
assembly.
2 Check the refitted hard disc starts up properly – power
up the equipment, click the mouse over the hard disc
icon and ensure a directory viewer appears.
Switching off the equipment
If you have completed service or tests on the system
and are about to move the computer and/or return it to
the customer, you must do the following before
switching off:
1 Shutdown the unit under test:
• press F12 and type SHUTDOWN (then press Return)
or
• select Shutdown from the Task Manager menu.
this parks the hard disc heads, if a hard disc drive is
fitted.
Part 1- Fault diagnosis and repair
Issue 1, November 1991
1-19
Part 2 - Disassembly and assembly
DANGER:
BEFORE REMOVING THE TOP COVER, ENSURE THAT
THE COMPUTER SYSTEM HAS BEEN SWITCHED OFF
AND THE MAINS PLUG REMOVED FROM THE SUPPLY.
REMOVING THE TOP COVER GIVES ACCESS TO THE
POWER SUPPLY. ALTHOUGH THE POWER SUPPLY IS
DESIGNED TO COMPLY WITH BS5850 CLASS 1, YOU
MUST STILL TAKE CARE TO ENSURE THAT NO METAL
OBJECTS FALL (OR ARE PUT) INTO THE POWER
SUPPLY UNIT THROUGH THE VENTILATION HOLES.
NOTE:
STRINGENT ANTI-STATIC PRECAUTIONS MUST BE
TAKEN ONCE YOU HAVE REMOVED THE TOP COVER.
3 Place the main unit on a work surface with a clean, soft
covering and turn it over so that it rests on its top cover.
4 Remove the six fixing screws (item 46) on the
underside of the main unit.
Introduction
This chapter tells you how to break down a standard
A5000 computer into its serviceable modules, in order to
carry out basic checks and replace modules found to be
faulty.
It is recommended that you remove modules in the order
given in this chapter, to ensure, for instance, that no
cables are left connected to the particular item you wish
to remove.
The main unit houses the following:
• Backplane*
• Main PCB
• 3.5" floppy disc drive
• Hard disc drive*
• Speaker
• Power supply unit (PSU).
*Hard disc drive models only
The keyboard, mouse and monitor are separate units.
See the appropriate third-party service information for
the monitor. The mouse is a service replacement only
item. This chapter makes reference (when it gives item
numbers) to the final assembly drawing (part number
0092,100/A) which you will find at the back of this manual.
Also see Appendix G - Final assembly parts list for a list
of part numbers.
5 Rest the main unit on its base again and slide the lid (
item 24) backwards to the rear of the unit. Remove
the lid completely.
6 Some models of the A5000 have an EMC case shield (
item 29) which fits over the case. To remove this
shield, unscrew the five fixing screws on the right hand
side of the unit, as seen from the rear. The shield has
interleaved tabs which fit into the edges of the case.
Slide the shield off the main unit carefully; there is a
hole on the top to help you slide the shield off by
inserting a screwdriver.
Removing the top cover
1 Shutdown the computer using one of the following two
methods:
• press F12 and type SHUTDOWN (then press Return)
• select Shutdown form the Task Manager menu
This shuts the computer down correctly and parks the
hard disc, if a hard disc drive is fitted.
2 Switch off and disconnect the computer from the
mains supply and then disconnect all peripherals,
including the keyboard.
Part 2 - Disassembly and assembly Issue 1, November 1991
2-1
Removing the backplane
Note that the backplane is only fitted on models with a
hard disc drive.
The backplane (item 9) sits inside the main unit, attached
to the main PCB and the backplane/drive tray (item 25).
1 Remove the four fixing screws from the backplane.
2 Remove the backplane from the main board connector
SK9 by pulling the backplane upwards.
3 Unscrew the two fixing screws on the lower blanking
panel and remove this panel, together with the gasket
shield (item 26). It is easier to slide out the PCB once
you have removed this panel.
4 The main PCB is positioned within four side slide
guides (item 5), two at each side. To extract the PCB
assembly, lift the rear panel slightly and slide the PCB
out along the slide guides towards the rear of the main
unit and out through the rear panel opening. Take care
not to damage the gasket fingers that are attached to
the rear panel on some models of the A5000.
Note: Observe all anti-static precautions when storing
the PCB.
Removing the disc drives
If your computer does not have a hard disc drive, ignore
all references to this item.
1 Remove the power connection from the hard disc drive (
item 78) which runs to the PSU (item 12).
2 Remove the power connection from the floppy disc
drive (item 77) which runs to the PSU.
Removing cables
1 Disconnect the following cables from the main PCB
which sits inside the main unit:
• the six power connections to the PCB, PL2 to PL7
• the speaker connection LK8
• the LED connection LK22
• the floppy disc drive data cable connection PL10
• the hard disc drive data cable connection PL9 If the
computer does not have a hard drive, ignore the above
reference to the hard disc data cable.
3 Remove the W-shaped EMC spring clip (which earths
the floppy drive to the main case) by pressing down
and hooking it out. See the diagram below.
Removing the main PCB
1 Some models of the A5000 have two fixing screws
which attach the PCB to the base metal work. One
screw is located near SK3, the other can be found near
SK8. Remove these screws from the PCB.
4 Undo the fixing screw which holds the backplane/drive
support tray (item 25), as shown in the following
diagram.
2 The rear panel of the computer is attached to the PCB.
Unscrew the two fixing screws on this panel. Note that
some models of the computer have an EMC gasket
sandwiched between the rear panel and the PCB.
2-2
Issue 1, November 1991 Part 2 - Disassembly and assembly
5 The tray has two tabs which fit into the front slots of
the unit and four clips, two at each side, holding the
tray in place. Remove the tray from the main unit by
grasping both ends of the support metalwork. The
whole
assembly should lift and the end tags disengage from
the sides. See the diagram below.
Removing the front plastic
moulding
1 There are six spring plastic clips on the front moulding (
item 28), three each on the top and bottom, attaching
it to the main unit. Release these clips from the inside
of the main unit.
2 Remove the plastic moulding. Note that there are two
LEDs in the front moulding, with wires attached. Feed
these wires carefully through the plastic panel.
Removing the power supply unit
1 Remove the plastic push button from the on/off switch (
item 32) on the front of the unit.
2 Undo the two fixing screws on each side of the on/off
switch socket.
6 Once you have removed the tray, you can remove the
floppy disc drive (item 77) and the hard disc drive (item
78) by turning the tray over and unscrewing the four
screws which hold each drive in place. Take care to
observe all anti-static precautions when storing the
disc drives.
Removing the speaker
Looking from the rear of the main unit, the speaker (item
36) is located on the right hand side of the unit.
1 Remove the rubber sealant (item 74) from each side of
the speaker.
2 Pull the speaker directly upwards and out of the main
unit.
3 Remove the earth wire from the earth fixing point,
easing the wire away from the harness clip at the side
of the unit.
4 The power supply unit itself (item 12) is held in place by
two screws which fix it to the base metal work of the
unit. Remove these two fixing screws together with
their washers.
5 Remove the four fixing screws at the rear of the unit.
6 Lift the power supply unit upwards and out of the main
unit.
Part 2 - Disassembly and assembly Issue 1, November 1991
2-3
Main unit assembly
PCB
On some models of the A5000, care is needed when
DANGER:
WHEN REFITTING OR FITTING A REPLACEMENT
ASSEMBLY, CHECKS SHOULD BE MADE FOR
EARTH CONTINUITY AND FOR DC INSULATION.
FOR DETAILS REFER TO Appendix C - Earth
continuity testing AND Appendix D - DC insulation
testing - class 1.
NOTE THAT THE PSU IS A SERVICE REPLACEMENT
ONLY ITEM.
Assembly is generally the reverse of the disassembly
procedures, but take care with the routing of cables and
ensure that leads are not trapped when refitting
assemblies to the main unit. The following points are also
worth noting when you assemble the computer.
Keyboard
The computer may be fitted with either one of two
keyboards:
• Panasonic (fitted on most models)
• Keytronic (on some early models).
Both keyboards are identical on the exterior; they only
differ internally, in that they have different PCBs.
Disassembly
1 Invert the keyboard and place it on a soft, level
surface.
Power supply unit
When installing the PSU, the system should be tested for
satisfactory earth continuity in accordance with
BS7002/EN60950 and DC insulation.
Ensure that you refit the earth wire exactly as shown in
detail B of the final assembly drawing (part number
0092/100/A), which you will find at the back of this
manual.
Also make sure that you connect the faston power
connections to the main PCB in the correct order, which
is as follows:
2 Remove the eight cross-headed screws securing the
two halves of the case and carefully lift the base
moulding away.
3 The PCB in the Keytronic keyboard is fixed to the top
moulding by six No. 6 x 0.25" screws.
The PCB in the Panasonic keyboard is fixed to the top
moulding directly by four screws, and also by means
of two metal brackets (with four screws and washers).
For the Panasonic keyboard, first remove the two
screws and washers fixing the brackets to the top
moulding, then remove the remaining screws fixing
the PCB directly to the moulding (you can leave the
brackets attached to the PCB).
PL2
-5V
purple wire
PL3
+12V
yellow wire
PL4
0V
black wire
PL5
0V
black wire
PL6
+5V
red wire
Assembly
PL7
+5V
red wire
Keyboard assembly is generally in reverse order, with
the following notes:
For the Keytronic keyboard, remove the six screws
fixing the PCB to the top moulding.
4 Note that the reset switch cap must be removed from
the original keyboard and fitted to the replacement.
Speaker
When refitting the speaker, ensure that you replace the
rubber sealant (item 74) on each side of the speaker.
Disc drives
When refitting the backplane/drive support tray, note that
the tray has two tabs which slot into the front of the main
unit and four clips, two at each side, holding the tray in
place. Ensure that the two tabs on the tray slide fully into
the slots at the front of the unit. If they are not completely
in place, there is a risk of damage to the disc drives when
the unit is moved.
2-4
assembling the main PCB to avoid damaging the EMC
gasket. As you slide the PCB board into the main unit lift
the rear panel, to ease the gasket fingers over the back
edge of the unit.
Slot the PCB support tray under the two fixing screws at
the end furthest from the keyboard cable, then insert the
remaining screws. Check that all keys clear the cutouts
in the top moulding before finally tightening all PCB
fixing
screws.
Mouse
The mouse is a service replacement only item.
Issue 1, November 1991 Part 2 - Disassembly and assembly
A5000
Module Level Service Manual
Appendix A - Mouse test jig template
1 Using wood or metal strips, construct a test jig with the
dimensions shown in the template (plan view) above.
2 Secure the test jig to a firm, flat, horizontal, non-slip
surface.
3 Mark out the three button boxes shown on the
template.
Notes:
• The INSIDE dimensions of the jig are important.
• The sides of the jig should be LESS than 5mm high.
• The Middle and Right button boxes overlap.
Appendix A - Mouse test jig template
Mouse in middle
button box
Issue 1, November 1991
A-1
Appendix B - Serial port loopback plug*
Item
Part no.
Description
Qty
Assembly notes
Assemble the components onto Veroboard, and fit item
5 (the shell) to protect the assembly
1
3
5
0276,081
0800,288
0800,991
CIRCUIT & ASSEMBLY DRAWING
CONR 9W SCKT 'D' ST MS SB
CONR 9W SHELL 'D' + SCREWS
1*
1
1
R1
R2
R3
R4
R5
R6
R7
R8
0502,122
0502,122
0502,122
0502,122
0502,472
RES 1K2 C/MF 5% 0W25
RES 1K2 C/MF 5% 0W25
RES 1K2 C/MF 5% 0W25
RES 1K2 C/MF 5% 0W25
RES 4K7 C/MF 5% 0W25
0502,472
0502,472
RES 4K7 C/MF 5% 0W25
RES 4K7 C/MF 5% 0W25
1
1
1
1
1
N/F
1
1
D1
D1
0790,085
0790,085
DIODE BAT85 SBL
DIODE BAT85 SBL
1
1
per batch
Appendix B - Serial port loopback plug
Issue 1, November 1991
B-1
Appendix C - Earth continuity testing
Test procedure
Equipment required
An earth continuity tester or appliance tester capable of sourcing
8-25A derived from an AC source with a no-load voltage not
exceeding 12V, for example, CLARE A433R-IO.
IIt is recommended that the calibration and operation of the
instrument is checked frequently enough to ensure its accuracy.
DANGER:
THE FOLLOWING TESTS INVOLVE HIGH CURRENTS BUT
LOW VOLTAGES. ALL NECESSARY PRECAUTIONS MUST
BE TAKEN TO ENSURE OPERATOR SAFETY DURING
TESTING.
DANGER:
SWITCH OFF THE COMPUTER, DISCONNECT IT FROM
THE MAINS SUPPLY, AND DISCONNECT ANY EXTERNAL
PERIPHERALS AND CABLES BEFORE CARRYING OUT
THIS TEST.
WARNING:
DO NOT MOVE THE TEST PROBE WHILST APPLYING
THE TEST CURRENT.
Before testing
Consult the instructions supplied with the test equipment. The
test should be performed on a fully assembled computer
and the equipment must be tested with the mains lead it
will be operated with.
Using the Earth continuity tester, check the continuity
between the power supply cord plug earth/ground pin and
the following points:1 the chassis upper wrap
(Note that if you need to remove the paint from the
upper wrap in order to make a good connection, do
this in a place where it will not be visible to the
customer. We recommend an area within the cooling
slots on the side of the upper wrap.)
2 the lower wrap (metalwork) on the base of the unit
3 the rear panel fixing screws (six screws)
4 the fixing bolts for
• printer/parallel port (D-type)
• Analogue RGB port (D-type)
• any other expansion cards (eg SCSI).
The resistance measured between the earth pin and each
of the above test points shall not exceed 0.15 Ohm. This
value includes an allowance for the resistance of the
mains cable. The duration of each test shall not
exceed 10 seconds. No waiting period between tests is
necessary.
Check the mains lead and plug for any physical damage and
replace if necessary.
WARNING:
YOU MUST NOT ALLOW THE
TEST PROBE TO TOUCH ANY
OF THE CONNECTORS' SIGNAL
PINS AS THIS WILL DAMAGE
THE EQUIPMENT.
Appendix C - Earth continuity testing
Issue 1, November 1991
C-1
Appendix D - DC insulation testing - class 1
UK information only
Before testing
Equipment required
Check the mains lead and plug for any physical damage
and replace if necessary.
A portable appliance tester or an insulation tester
that provides 500V DC ONLY.
Note that the computer contains RFI capacitors on
the PSU input.
It is recommended that the calibration and operation
of the instrument is checked frequently enough to ensure
its accuracy.
DANGER:
THE FOLLOWING TEST INVOLVES HIGH VOLTAGES. ALL
NECESSARY PRECAUTIONS MUST BE TAKEN TO
ENSURE OPERATOR SAFETY DURING TESTING. NOTE
THAT THE OPERATOR MUST BE TRAINED AND
COMPETENT.
DANGER:
SWITCH OFF THE COMPUTER, DISCONNECT IT FROM
THE MAINS SUPPLY, AND DISCONNECT ANY EXTERNAL
PERIPHERALS AND CABLES BEFORE CARRYING OUT
THIS TEST.
Test procedure
Consult the instructions supplied with the test equipment.
The test should be performed on a fully assembled
computer.
The equipment must be tested with the mains lead it will
be operated with.
1 Insert the mains lead either into the portable appliance
tester, or into an adaptor, as shown below.
2 Move the computer's power switch to the ON position.
3 Apply the test voltage for LESS than 10 (TEN)
seconds and then measure the resistance.
4 Pass level: GREATER than 2 (TWO) Ma
5 Move the computer's power switch to the OFF position
and remove the mains lead from the portable appliance
tester.
Testing with an insulation tester
Insulated terminals and leads
Appendix D - DC insulation testing - class 1 Issue 1, November 1991
D-1
Appendix E - Monitor adaptor cables
This appendix describes how to make adaptor cables for
monitors not supplied with a 15-way VGA connector.
Adaptor type 1
Adaptor type 3
The cable supplied with some TV-type monitors is
terminated at the computer end with a 9 pin D-type plug.
You need a 15-way plug to 9-way socket adaptor:
The cable supplied with some Multiscan monitors is
terminated at the computer end with a 9-way D-type plug.
You need a standard 15-way plug to 9-way socket
adaptor:
Note: The HSYNC to ID[0] connection will make the
monitor type 0 modes available and the computer will
generate a composite sync signal.
Note: The ID[O] to OV connection will make the monitor
type 3 modes available and the computer will generate
separate sync signals.
Most Multiscan monitors are now being designed to be
VGA-compatible and will work satisfactorily when driven
with separate horizontal and vertical sync signals.
Cable type 4
You need to make this cable to use with televisions and
TV-type monitors using a SCART input socket:
Adaptor type 2
The cable supplied with some Multiscan monitors
requiring composite sync is terminated at the computer
end with a 9 pin D-type plug. You need a 15-way plug to
9-way socket adaptor:
The 220Ohm resistor results in a CSYNC signal of
approximately 1V peak on pin 20 of the SCART connector.
The 75Ohm resistor results in a blanking signal of
approximately 2.5V dc on pin 16 of the SCART connector.
Note: The HSYNC to ID[2] connection will make the
monitor type 1 modes available and the computer will
generate a composite sync signal.
Appendix E - Monitor adaptor cables
issue 1, November 1991
E-1
Cable type 5
You need to make this cable to use with monochrome
monitors which have a phono input socket. You need a
15-way plug to phono socket adaptor with resistors, to
mix the separate red, green and blue signals into a
composite monochrome signal (you can fit these
components into a 15-way connector shell).
You need to make an adaptor cable that has a 15-way Dtype plug on one end, and a phono plug on the other. The
connections you need to make are as follows:
Note: The HSYNC to ID[0] connection will make the
monitor type 0 modes available and the computer will
generate a composite sync signal.
E-2
Issue 1, November 1991
Appendix E - Monitor adaptor cables
Appendix F - Main PCB links, plugs & sockets
Introduction
Link
Fitted
This appendix describes the links, plugs and sockets on the
main PCB of the A5000 computer.
LK8
Yes
LK9
Effect
Yes
P1
P2
Shunt 1-2
Sig. option
LK1
PC Kbd clock
2-3
KIN data
1-2
LK10
Yes
Shunt 1-2
inverted Kout from
IOC
logic 1
2-3
None
Internal auxiliary audio
connector providing access to
the following signals:
P1
P2
P3
P4
P5
P6
P7
P8
P9
P10
LK11
3-4
3-4
JEDEC 1, 2, 4, and
8MB ROMs and
EPROMs
2-4
Shunt 1-2
LK12
Yes
LK13
No
SIZE (Bits) LK14
LK11
LK12
1M
2M
4M
8M
2-3
2-3
1-2
1-2
2-3
2-3
2-3
1-2
2-3
1-2
1-2
1-2
See LK11.
Shunt 2-3
Used to select the source of
1-2
Parallel port Interrupt for IOEB
1-2
parallel port ACK' signal
2-3
PINTR* from 82C710
LK4
LK14
LK15
2-3
1-2
Used to select the source of
Yes
Yes
1-2
Keyboard in data
from controller (IC6)
2-3
Kin data
from keyboard
Shunt 1-2
Used to select '5th column' ROM
size (JEDEC only device).
Shunt 2-3
LK17
Genlock connection point:
Shunt 1-2
See LK11.
"Keyboard In" data for IOC.
LK6 Yes
1-3
Yes
Shunt 1-2
Used to select signal options for
pin 1 of keyboard socket (SK4).
PC bidirectional
data
reset from Kbd
Shunt 2-4
Non JEDEC 512K
1-2
Non JEDEC 1MB ROM 1-2
Non JEDEC 1MB
EPROMs
Used in conjunction with LK14
and LK12 to select ROM SIZE:
Unfiltered Left
OV
Left Phones
OV
Aux Input
OV
Right Phones
0V
Unfiltered Right
0V
Sig. option
Shunt 1-3
Used to select ROM TYPE:
TYPE
Used to select the signal source
to pin 6 of the keyboard socket
1-2
LK5 Yes
None
5V
D[0]
D[0]
LA[21]
TESTAK
RST*
OV
P3
P4
P5
P6
(SK4).
LK4 Yes
OV
Signal
Test connector used in
conjunction with Acorn
designed test equipment:
Used to select signal options for
pin5 of keyboard socket (SK4).
LK3 Yes
None
Connection point for the internal
speaker:
Default
LK1 Yes
LK2 Yes
Default
P1
P2
Links
Unk Fitted
Effect
Yes
Size (bits)
up to 1M
LK15
2-3
2M
1-2
Used to select Normal or
None
Alternate pre-compensation
scheme for floppy drive interface
Shunt 1-2
Shunt 3-4
P1
Internal video
dock
P2 Clock to VIDC
P3 SINK
P4 OV
P5 nc
P6 nc
P7 VED0*
P8 VED1*
P9
VED2*
P10 VED3*
P11
SUPREMACY'
P12 HI'
P13 HSYNC*
P14 VS*
P15 OV
P16 OV
Appendix F - Main PCB links, plugs & sockets
Pre-comp
LK17
Normal (125ns @ 500kb/s)
1-2
(125ns @ 250kb/s)
Alt
(125 ns @ 500kb/s)
None
(250 ns @ 250kb/s)
LK18
Yes
Used to select the polarity of the
Shunt 1-2
Mode select signal routed
to pin 3 of LK19.
Polarity
LK18
PC-AT
1-2
PS/2
2-3
Issue 1, November 1991
F-1
Link
Fitted
LK19
Yes
Effect
Default
P1
PL8
P3
No
Floppy disc power connector.
P2
P3
P4 nc
PL9
IDE hard disc drive data connector. This is a
Yes
40 way box-header containing all the signals
required by the drive in AT mode.
Shunt 1-2
Used to connect pin 34 of floppy
drive connector B (PL11) to the
DISC CHANGE I/P of 82C710
P1
P2
P3
LK22
Yes
Yes
DISC CHANGE VP
on 82C710
Pin 34 of drive
connector
nc
None
Connection for Power and Hard
disc activity LEDs.
P1
P2
P3
P4
LK23
HID LED (-)
H/D LED (+)
Power LED (-)
Power LED (+)
None
Used in conjunction with LK24 to
select various combinations of
DRAM on the main PCB and the
memory upgrade card.
Total
DRAM
DRAM on PCB
LK24
Yes
Function/Specification
P1 +5V
DISC CHANGE VP on
820710
Pin 2 of disc drive
connector
MODE SELECT (polarity
depends on LK18)
P2
Yes
Fitted
Shunt 2-3
Used in conjunction with LK18
to select the function of pin 2 of
the Floppy disc drive data
connector B (PL11).
LK21
Plug
DRAM
on UM
card
Signal
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
RST*
DATA?
DATA6
DATA5
DATA4
DATA3
DATA2
DATA1
DATA°
37
39
CSO
SLV/ACT
Pin
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
nc
IOW*
IOR*
IORDY*
nc
IRO
LA[3}
LA[2]
34
36
38
40
Signal
DATA8
DATA9
DATA10
DATA11
DATAl2
DATA13
DATA14
DATA15
nc
nc
IO16*
PDIAG*
LA[4]
CS1*
LK23 LK24
PL10
1M
2M
4M
2M
4M
1M
2M
4M
1M
1M
–
–
–
1M
3M
nc
nc
nc
nc
1-2
nc
2-3
1-2
2-3
2-3
4M
2M
2M
1-2
2-3
Yes
Floppy Disc Drive Data Connector A. This is a
34-way Box Header containing all the signals
required by the internal floppy disc drive(s).
Pin
2
4
6
8
10
12
14
16
18
Modeldependent
See LK23.
1MB machine
2MB machine
4MB machine
Pin
nc
2-3
1-2
Signal
MODE SELECT
nc
nc
INDEX*
DRIVE SELECT 0*
DRIVE SELECT 1*
nc
MOTORON*
DIRIN*
Pin
20
22
24
26
28
30
32
34
Signal
STEP*
WRITE DATA*
WRITE GATE*
TRACK0*
WRITE PROTECT*
READ DATA*
SIDE1*
DISC CHANGE
* All signals are active low.
3,13,15,17,19,21,23,25,2729,31,33 all
Plugs
5,7,9,11.
PL11
Fitted
Function/Specification
PL1
Yes
Serial Port. (IBM PC-AT Pinout)
9-way D-type plug.
PL2
to
PL6
Signal
DCD
RxD
TxD
DTR
5
0V
Pin
6
7
8
9
Signal
DSR
RTS
CTS
RI
Power supply connectors.
PL2
PL3
PL4
PL5
-5V
+12V
0V
Floppy Disc Drive Data Connector B. This is a
34-way Box Header containing all the signals
required by a variety of internal/extemal
drives.
Plug
Pin
1
2
3
4
Yes
PL6
PL7
+5V
+5V
Pin
2
4
6
8
10
12
14
16
18
Signal
See Note
nc
nc
INDEX*
DRIVE SELECT 2*
DRIVE SELECT 3*
nc
MOTORON*
DIRIN*
Pin
20
22
24
26
28
30
32
34
Signal
STEP*
WRITE DATA*
WRITE GATE*
TRACK 0*
WRITE PROTECT*
READ DATA*
SIDE1*
See Note
* All signals are active low.
3,13,15,17,19,21,23,25,27,29,31,33 all
5,7,9,11.
Note: Pins 2 and 34 have several functions,
depending on the positions of LK19, 18 & 21.
F-2
Issue 1, November 1991
Appendix F - Main PCB links, plugs & sockets
Sockets
Skt
Fitted
Function/Specification
SK1
Yes
RGB video socket.
This is a 15-way mini D-type socket providing
an interface to RGB monitors and Scan TVs.
RGB video levels are 0.7V Pk-Pk into 75 Ohm.
Sync voltage levels are >= 2.0V (TTL).
Pin
Signal
1
2
3
4
5
6,7,8
9
10
11
RED
GREEN
BLUE
ID[2]
OV
+5V (750mA fuse)
OV
IT)
ID 1 /SCARY
func. switching
H
NC
12
13
1
14
15
SK2
Yes
VSYNC/CSYNC
ID[3]
Stereo headphone output.
This is a 3-way 3.5mm stereo jack socket
providing output to "Walkman-type" 32 ohm
stereo headphones.
SK3
No
9-way mini-DIN providing connection for
quadrature mouse. Reserved for future use.
SK4
Yes
6-way mini-DIN socket providing the
connection point for the keyboard.
SK5
Yes
Parallel printer port.
25-way. D-type socket providing a parallel
printer interface.
Pin
2
3
4
5
6
7
SK6
Yes
Signal
PD
PD
PD
PD
PD
PD
Pin
1
PD[6]
1
0"
2
3
4
5
Signal
STB* 8
10
9
11
12
13
14
Pin
15
7
17
AC
PD
BSY
PE
SLCT
AUTOFD*
Signal
16
18-25
ERROR*
INIT*
SLCTIN*
OV
Econet socket.
5-way DIN socket for connection to Econet
LAN. Note, this is an upgrade.
SK7
Yes
Pin
Signal
1
2
3
4
5
DATA
OV
CLOCK*
DATA*
CLOCK
Econet upgrade module socket.
17-way header used in conjunction with SK8
to provide the electrical connection point for
the internal Econet upgrade module. This
module is identical to that used on Acorn
Master series and Archimedes computers.
SK8
Yes
Econet upgrade module socket.
5-way header used in conjunction with SK7.
SK9
Yes
Backplane socket.
Systems are normally supplied with a 4-way
backplane already installed.
SK10
Yes
Mem expansion socket (1, 2 or 3MB upgrade)
Appendix F - Main PCB links, plugs & sockets
Issue 1, November 1991
F-3
Appendix G - Final assembly parts list
Introduction
The parts list in this appendix details the components used in
the final assembly of the Acorn A5000 computer. These
components, together with their corresponding part
numbers, are illustrated in the final assembly drawing given
at the end of this manual.
Final assembly (Hard and floppy
disc versions)
Note: Items in bold are only in the hard disc machine.
Item
1
4
5
6
9
12
16
17
19
20
23
24
25
26
28
29
30
31
32
34
35
36
39
40
45
46
48
49
53
54
56
58
62
65
69
73
74
76
77
78
Description
Qty
FINAL ASSY DRG (1 PER BATCH)
DOUBLE BLANKING PANEL
PCB SIDE SLIDE GUIDE
'NO ECONET' LABEL
BACKPLANE (4W) PCB BoM
BRISBANE [240V) PSU
FRONT LABEL
BASE LABEL
PSU IEC "IN" LABEL
PSU IEC "OUT" LABEL
LOWER CASE
UPPER WRAP
BACKPLANE/DRIVE TRAY
DOUBLE PODULE EMC GASKET`
FRONT MOULDING
CASE EMC SHIELD*
FLOPPY APERTURE COVER
BLANKING PANEL - FLOPPY
PLASTIC PUSH BUTTON
LED CABLE ASSEMBLY
DISC DRIVE CABLE ASSY
SPEAKER CABLE ASSEMBLY
MAIN [2M} PCB BoM
HARD DISC CABLE ASSY
SCW M2.5x6 PAN HD POSI
Use on Items 4,26,39.
SCW M3x6 PAN HD POSI
Use on Items 9,12,24,29,30,77.
1
2
4
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
6
NUT M4 STL FULL Z/PASS
Use on Item 23.
WSHR M3.5 PLN STL Z/PASS
Use on Item 12.
WSHR M2,5 PLN STL Z/PASS
Use on Items 4,26,39.
WSHR M3 SPRF IT STL
Use on Item 12.
WSHR M4 SPRF IT STL
Use on Item 23.
RIVET POP 3,2DIA x 6,41 L
Use on Item 5.
SPCR NYL 8mm PCB GAP 1 END
Use on Item 39. (Option)
PCB SPACER 8mm
SCW6-32UNCx1/4" PAN POSI
Use on Items 12,78.
FOOT PUSHFIT 21Dx4,2H
ADH MATL RUBR SEALANT
Use on Item 34,36.
LABEL SERIAL No GP 50x15
FLOPPY DRIVE 1/2 MB 3.5"
WINI DRIVE 40MB 3.5" IDE
(Caution when handling)
2
25
4
6
2
2
4
1
8
4
A/R
1
1
1
* Not fitted on early models of the A5000.
Appendix G - Final assembly parts list
Issue 1, November 1991
G-1
Reader's Comment Form
A5000 Module Level Service Manual
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