^
The Aston Martin Lagonda Diagnostic System
Users Guide
Parameter Name
Parameters can be fault codes, inputs to, or specific
outputs from, a vehicle control module.
The number of parameters selectable is limited to 32.
If the number of parameters available for customization
exceeds the d isplay
area,
the arrow buttons wi
11
be present,
allowing display area scrolling.
The parameters declared to Datalogger are initially
presented in alphabetical order.
Record Enabled
Record enabled is used to select which signals are to be
recorded.
To select a signal for recording, touch the rectangle next
to the signal name.
The record button will then be displayed.
Nofe:
Additional rectangles may appear in other columns
beside a selected signal name, indicating that the signal
units may be changed or that the signal may be used
as
a
trigger.
It should be noted that the more parameters you select to
record the slower the PDU's sample rate will be for each
parameter e.g. The PDU may be able to monitor six
parameters sampling each parameter twice a second. If
the number of parameters is increased to twelve then the
PDU would only be able to sample each parameter once
per second, thus reducing its ability to capture fast faults;
therefore it
is
recommended that the number of parameters
is kept to a minimum.
Display Order
Parameters may be displayed on the waveform/ bargraph
screen in any order.
To set the parameter display order, press the required
rectangle to create a numbered list.
Note: It
is
not
necessary to
display all of the parameters
required to be recorded.
This has particular benefits if a parameter is to be used as
a trigger but is not required to be displayed.
Trigger Action
For a detailed description of trigger action, refer to the
Trigger Customisation description on the following page.
S.I.
Units
Certain parameters can be measured / displayed in a
number of different units eg temperature in °C or °F. If a
rectangle appears around the displayed units in the
'S.I.'
column then the units are selectable. Each time the
rectangle is pressed, the selectable units scroll one step
through the available options.
Other Features
To make parameter customization easier two icons have
been introduced on to the bottom of the screen, these are:
This icon simply puts all ofthesignals selected for
recording in alphabetical order irrespective of
the language.
A B C
This icon will put all of the signals selected for
recording at the top of the parameter list in
numerical order.
^T/^
After the parameter customization process is completed,
return to the Datalogger main menu.
Default Customisation
To cancel all customisations, press the
Customisation Reset
icon.
This will reset the
customisation on all parameters to the default
setting.
Trigger Customisation
Datalogger operates using a 'rolling memory'.
When the Record icon is selected on the waveform
display, PDU will start to record data, it will then continue
to record data until its memory is
full.
At this point it will continue recording by overriding the
oldest
data.
This process will continue indefinitely or until
the trigger is activated.
When the trigger is activated it performs a number of
functions.
a) The first function istoplaceazerotimepointwithin
the stored data, this enables the trigger point to be
easily accessible in later stages.
b) The second function is to set a timer, ensuring that
the PDU wil
I
only continue recording for the time
selected in 'test-duration'.
September 1996 9-57
The Aston Martin Lagonda Diagnostic System
Users Guide ^?
Datalogger Timing
Select the 'clock' icon from the main menu screen.
Confirm the selection using the 'tick'
icon.
The Datalogger timing screen should now be displayed.
Datalogger Timing
Signals
Sample Interval
Record time
Pre-trigger
Post-trigger
00:33:20
50%
00:16:40
50%
00:16:40
'^
23]
Datalogger Timing
The Datalogger timing screen allows customisation of the
sample interval and duration of data capture.
The display will identify the number of parameters
(channels) which have been selected to be recorded by
Datalogger.
Timing changes can only be made while data capture is
inactive. Entering Dataloggertiming while vehicle data is
being captured will display the current
settings,
but disable
selection.
Signals
The signals are the number of parameters set for sampIing
by Datalogger.
Sample Interval
The sample interval (frequency) defines the time interval
between successive block requests for all recorded
parameters.
The sample interval is selectable to enable fast response to
intermittent faults.
Note: Very short sample intervals may reduce test
duration
because ttie
PDU memory
becomes
full of
data.
Select the sample interval rectangle.
Acaiculator-style icon should nowbedisplayed. rrr?]
^
Aswellasa calculator-style icon beingdisplayed
there will bea hare
icon,
selecting this icon will
automatically set the fastest sample rate for the
selected parameters.
Note: The fastest sannple rate set using the 'hare' icon may
be too fast for some applications.
Select the calculator-style
icon.
A new screen should now be displayed.
Enter Test Duration
IDD 33 EDI
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1
1 2 1 3 1
0
1
Test Duration
Enter the required value in milliseconds up toa maximum
of 60,000 mS (1 min). At this stage Datalogger will not
verify if the entered sample interval can be achieved.
When Datalogger is actioned to start recording vehicle
data,
and the sample interval is shorter than the fastest
achievable capture time, a warning screen will be
displayed,
requesting changes to the sample interval.
Record Time
The record time (test duration) defines the length of the
data slice which will be preserved for analysis after the
fault occurs. The selected time will be split equally before
and after the fault trigger, e.g. a 10 minutes recording will
preserve data from 5 minutes before to 5 minutes after the
fault.
At the end of the record time the PDU will automatically
stop recording.
The record time is entered in the same way as the sample
interval,
by enabling the rectangle and selecting the
calculator-style
icon.
9-60 September 1996
