Service manual

Service Manual
Action if printer test fails
Check that the configuration settings for PRINTER
and IGNORE are correct.
Check that the correct type of printer is called in the
test data file, or check your notes when running the
configuration program earlier in the test.
Check that the printer is on line and that the printer
lead is connected correctly and functions correctly.
If the fault still persists then either change the main
PCB, or see Part 5 - Main PCB fault diagnosis.
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 or the RISC iX 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, either change the main PCB, or
see Part 5 - Main PCB fault diagnosis.
NOTE: During the soak tests neither the printer nor the
RS423 tests are executed.
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
Replace the BLANK
DISC
in drive :0
Insert the 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_NAFF 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.
Mouse tests
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 (ie 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.
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.
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 is a FAIL.
If you press the wrong mouse button and the pointe
r
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 display is put into inverse video and
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.
You should repeat the test with the known good
mouse to isolate the fault to either the keyboard or
the mouse. Replace faulty components then retest.
If everything is normal the program moves on to the next
test.
Action if test fails -
Check the correct mouse type is being tested by reading
the data file, or by referring to your notes made when
running the configuration program earlier in the test.
Ensure 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 then try using a known
good mouse of the same type.
4-12 Issue 2, June 1991 Part 4 - Fault diagnosis