Not sure why case structure dont work?

[Troy]

So here is what I understand you need this to do...  We are going to setup a test on the PC and when you press a button on the test equipment it will start sending data to the PC via serial port.  Once the test is completed, you will select the next test setup in the PC, which will change the test configuration, then press the button on the test equipment again to start the test.  Again data will be fed to the PC from the serial port for logging.

If this is correct, let me look at your VI and see if I can explain the changes needed to do this. 

Things have been a bit hectic around here the last couple of days, and our network is having issues as well, so I apologize for my slow response the last couple of days.  Thanks for the paitence.

[Printerman]

Hi Troy,.

thanks for helping me with this. Let me give you more detail as its still not quite right. The Insertion loss(IL) string is short. Once the string is sent i would like it to automatically switch over for return loss(RL). Once that string has been captured i'd like it to auto-switch back again. This is a singlemode(SM) test only.

The multimode(MM) test only requires the insertion loss test hence no switch over required.

The string example for MM/SM insertion loss looks like;

ABS 28/01/09 10:27:28
0850nm -51.17dBm

The string example for the SM return loss looks like;

RT1 02/02/09 14:29:09
0850nm (1) +69.00dB

So i need to do repetative insertion loss tests for MM product but  would like an auto switch over to RL after insertion loss test. 

Hope that makes sense.!

Thanks

G.

[Troy]

I am beginning to get the idea.  Are the strings you show are the data returned from the test equipment or the data the PC needs to send to initiate the test?

You know what would really help us (me ) here is drawing a flow chart of how the test should run from beginning to end, including how to start and stop the testing and the decision points. In essence when we build the state machine code, we are going to follow that flow.  A state machine is a while loop around a case structure, where each case is a step in the process.

[Printerman]

They are the strings from the Test kit. The strings to control the machine are the write strings i have included on the VI...i think they sre correct.

G

[Printerman]

Hi been looking at this! Driving me crackers.

Couldn't i use a stacked sequence structure to execute the insertion loss test then switch to return loss test and back again. I'm trying to get this to work but i'm truggling to get it going....arrgghh!!