Please help with structure of my program

Question

I am hoping someone can help me with a motor control program that I am
writing.  The program is too large to post here, but I attached a
rough outline of the program.  I think the problem is with the
higher level logic, so hopefully that will provide the necessary
information. 
I have a front panel with lots of buttons to control the motors (eg:
power, stop, start).  There is an event structure that contains
most of those buttons (power, start, etc), but if that structure is
exectuting, the other buttons won't work.  I need to be able to
stop the motors and exit at any time (for safety), so I made another
event structure that contains the stop and exit buttons.  Is this
the right way to do this?
Also, I want all the loops in the program to run continually until the
exit button is pressed.  Since the exit button actually calls
exit.vi and closes the whole program, I just wired a F constant to the
stop on the while loops so they never stop.  Could this be causing
my problems? 
Hopefully I provided enough information here, but if not, please write back and let me know.
Thanks,
Kasey
PS. In case anyone wonders why the whole thing is in a sequence, I need
it for other aspects of the program (safety lights, etc...).  I
doubt it makes a difference, but I wanted to include it.
Attachments:
screenshot.jpg ‏258 KB

Answer 1

This is the first time I have seen a case where it is useful to have two or more event structures in one program.  Since they are in separate parallel loops, I would think there would not be a problem.  I like the idea that the program can be stopped in the middle of an event, for safety reasons.  Great structure, Kasey.  The only thing I would add is to make sure that your exit vi gracefully shuts down the program.  Like if files or references are open, they get closed before terminating the vi.  Just be on the look out for race conditions since you have 3 events that can happen at one time.  One event might affect some indicator that is being handled by another event.  Also, instead of wiring a false to the other loops, maybe you could use local variables of one general stop boolean.  Since your exit vi stops all execution, it may not make much of a difference.
- tbob
Inventor of the WORM Global