> It's not hard, just tricky because 
>alot of this depends on how exactly FB passes its parameters.

FB pushes all of its parameters on the stack as long integers, left to 
right. The last parameter, however, stays in register D0 and does not get 
put on the stack.

The return value goes in D0, unless the function returns a string, in 
which case the return value is a pointer to the string which goes into A0.

-Mars