Hi Hank,
I'm not sure I can give you a general way of doing it.

One (obvious but not elegant) way is to simply check the flag several times as you go thru the main loop.

Another way, assuming you're using some kind of counter/index variable to "step" thru the individual states of each pattern, is to also reset that counter in the ISR thus forcing the "cycle" to start over. If the first thing you do in the "cycle" is to check the "pattern variable" then you'll get an imidiate switch of patterns.

I'm sure there are several other ways of handling it.

/Henrik.