Predefined Sequences

A LTT testplan need to have certain predefined sequences.

See chapters order of execution, operation modes and process model for a better understanding.

Standard Sequences 1

The green and purple sequences at the top are predefined mandatory TestStand sequence callbacks triggered by the process model. They will be triggered in the following order.

1. SequenceFileLoad: called at sequence file load. Initializes limits.

2. ProcessSetup: called one time after start for all stations. Use this to perform initializations per LTT and not per DUT.

3. PreUUTLoop: called one time after start for each DUT.

4. MainSequence: main sequence entry point. Do not make any changes here. It serves as a dispatcher to the various operation mode sequences.

5. PostUUTLoop: called one time during stop for each DUT.

6. ProcessCleanup: called one time during stop for all stations. Use this to perform cleanup per LTT and not per DUT.

Standard Sequences 2

Additionally to the standard TestStand sequence callbacks there are a couple of other, optional sequences.

Sequence	Outcome
Sync	Synchronizes the execution of all stations at this point. Optionally sets the power supply to a different voltage level.
MesSy Setup	Performs the MesSy setup.
MesSy Analog Config	Configures MesSy analog channels (scaling, offset).
MesSy Activate Limits	Activates a given limit set on MesSy.
MesSy SSV Check	Performs a SSV check on a given limit set.
MesSy Clear Errors	Clears any previous SSV check results.

Besides those standard and optional sequences above, there are so called operation mode sequences, which are important for the LTT.

A LTT testplan need to contain at least one operation mode sequence.