Ok... I am back with a similar issue. I've decided to place a flag in the callback function that I will clear upon execution. I have the flag as a private member of the class. When I attempt to clear it inside the callback function with:

pulsing=false;

I get:

illegal reference to data member 'FOO:ulsing' in a static member function

The error makes sense because the this pointer is not passed along. I figured declaring the flag as

static bool pulsing;

would solve this issue... but that generates an unresolved external symbol.

Any help?