Snapshot

Here follows an example showing how the "Snapshot" function can be used to record data from the "Automatic transmission (TCM)" system.

By selecting "Diagnosis'"/"(S) 1995"/ "SAAB 900" / "F1: Transmission"/ "Automatic transmission (TCM)" in the main menu, you will end up in the system menu shown on the right.
Select "F2 Snapshot".





Trigger
Before starting to record a "Snapshot", you must select the desired type of recording. This is done by selecting the desired "Trigger type". Trigger means "go" and by selecting the type of trigger you determine what it is that will cause recording to start.

There are three types of "Trigger Type" in "Snapshot":

1. "Any Code" means that recording starts as soon as a diagnostic trouble code is generated in the relevant system's control module. This function has not yet been implemented.

2. "Single Code" means that recording starts only if the diagnostic trouble code which the operator has set is generated in the control module.
This function has not yet been implemented.

3. "Manual Trigger" means that recording is started manually by the operator.





The next step is to decide the "Trigger Point" which determines how the recording time will be used in relation to when the "Trigger Point" is activated.

In "Snapshot", three different positions can be selected for the trigger:

1. "Beginning", which means that activation of the trigger causes recording to start and that the entire recording after the trigger is saved.

The trigger is activated by pressing the "Trigger" display key.





2. "Centre" means that recording starts when all settings have been made. When the trigger is activated, recording continues for a while so that half the recording occurs before and half occurs after the trigger on the time axis.





3. "End" also means that recording starts when all settings have been made. When the trigger is activated, recording ends and the entire recording occurs before the trigger on the time axis.

Select "F8: Record Snapshot".

For an example of "F9: Play Snapshot", see the section entitled "View Captured Data".





Yet another way of adapting recording to the requirements of the moment is to select the group of signals to be recorded.

The categories differ between different systems.
1. "F0: All" means that all available values will be recorded.
2. "F2: Inputs" means that only those values obtained from the system's own sensors or other control modules will be recorded
3. "F3: Outputs" means that only those values sent out by the control module will be recorded.

In general, the maximum recording time increases when the number of recorded values decreases. For instance, if the recording of output values only is of interest, recording time can be extended by selecting outputs instead of all values.

Select "F0: All" to record all the values.





If the "Any Code" or "Single Code" trigger type is selected, "Snapshot" recording will start when the menu on the right appears.

Recording of a "Snapshot" will now take place at the same time as all read values in the relevant control module are shown on the display.

The message "Standby" at top right in the display flashes to indicate that the Tech 2 is waiting for a trigger signal.





Select Values
In "Snapshot' mode also you can take a look at a number of values. This does not affect the recording which records the entire selected category.

Press the "Select Values" display key to select up to 5 read values for display at the top of the list.





Select the desired value by marking it and then press "ENTER".

Selected values are marked with an asterisk "*" at the beginning of the line.

When 5 values have been selected, one of the values must be removed before a new value can be selected.





Press the "Display Values" display key to show the selected values at the top of the list of read values.





If you want to remove selected values and return to the list with no selected values, proceed as follows:
Press the "Select Values" display key.





Press the "Clear All" display key to remove all values.





Press the "Display Values" display key to return to the list of all available read values.





The message "No parameters selected" will be displayed for about 3 seconds and after that the list of read values will again be displayed.





Here is the menu with all the system's available read values again.

Press "EXIT' to return to the menu in which different categories of signals can be selected.

Press "EXIT' again to return to the menu with "Trigger position" and "Trigger Point" options.

Press "EXIT" once again to return to the system menu.





Trigger
Press the "Trigger' display key at the desired time to set the "Trigger Point".





Since the middle "Trigger Point" has been selected here, recording continues for a length of time corresponding to the time it takes to fill half the memory available for the "Snapshot" concerned.

If a shorter recording time is desired, recording can be interrupted by pressing "EXIT" at the desired time.





When the memory is full or recording is stopped, the message "Please wait .......Storing Snapshot Data" will be displayed during the time it takes to save data to the memory card.





When the recording has been saved, it will be played back immediately.

Here is the menu with available read values from the recording.

Press "EXIT" to return to the menu containing the "Trigger position" and "Trigger Point" options.

Press "EXIT" again to return to the system menu.





More
Press the "More" display key to see other available display keys.





Here are other available display keys in the system concerned.





Units
Press the "Units" display key to alternate between metric and English units.





The display now shows English units.

Press the "Units" display key again to return to metric units.





Previous List, Next List

Press the "Previous List" or "Next List" display key to alternate between categories of read values.

Press the "Next List" display key.





The display now shows available read values from the "Inputs" category.

Press the "Next List" display key to see available read values from the "Outputs" category.

Press the "Next List" display key once more to see available read values from the "All" category again.

By using the "Previous List" display key instead, the categories of read values will be changed correspondingly in reverse order.

Press "EXIT' to return to the menu with "Trigger position" and "Trigger Point" options.

Press "EXIT" again to return to the system menu.