Batch testing using the Sequencial Model

[jtc@mds]

One of our Test Engineers is uncomfortable with the Batch Model provided with TestStand 2.  Is there an easy way of using the Sequential Model as a Batch Model (testing multiple UUTs).  The way I understand it, there is much more flexibility and capability built into the Batch Model, but I'm having a hard time convincing him and our boss of that.  It seems as though by the time you get done modifying the Sequencial Model to do Batch testing, you've basically created a custom Batch Model anyway.  And if that's the case, why not use something that was already designed specifically for that purpose.  Am I looking at this correctly?

[Norbert_B]

jtc,

you are correct in your understanding regarding the basics of the two different models. The sequential model is designed to test a single UUT at a time. The batch model expands this to test as many UUTs in parallel as you like, but the execution is synchronized on some points for the UUTs. This is done because we asume that the UUTs are connected together somehow e.g. placed on the same carrier. So each execution first handles things for all UUTs once (like retrieving/positioning of the carrier) and then starts to test each "socket" (meaning each UUT). After each socket has finished, the carrier is removed and a new one has to be placed in the fixture.

Since i dont know TS 2.0 (i started with 3.0) i am not sure where the differences are regarding processmodels. In TS 3.x, you have a third processmodel called "ParallelModel" which does not contain logical dependencies between the sockets.
Another thing about the BatchModel is that you can insert "synchronized sections" where you can "change the way of execution in parts of your sequence". One possible setting is e.g. "One thread only" which makes sure that the sockets synchronize at the beginning of the section and then only ONE socket executes the content of the section. After this, all sockets continue testing.

Another "problem" which is encountered by many beginners is that both parallel and batch model copy the initial sequence for all sockets. So each socket does the same tests which is propably not wanted.
Nevertheless, you can change the execution by including all tests for all sockets. Then create appropriate preconditions where you check for the socket you are currently working on. The needed Lookupstring would be "RunState.TestSockets.MyIndex"....

hope this helps,
Norbert B.