[Jay Lundy]

Yeah, I think the hardware stack is 32 bytes, so subtract a few from already nested CALLs and you can get about 28 recursions. I doubt you'd need or use that many though.

For your second question, it depends on what modifier the variables have in front of them. See the compiler docs in your mcc18/docs folder.

The auto modifier is the default one (it's default by default, you can make static default if you want). Auto variables are the ones you are used to. They just get shoved somewhere in memory when you declare them and go away when they lose scope. So with recursive functions if you have a bunch of auto variables you allocate new memory for them each recursive call. That way when you leave the recursive function the original varaibles are still intact.

The static modifier defines them globally, but they have the same scope as an auto variable. So if you define them in a function you can only access them in that function, but the variable never gets deallocated, so you can transfer the same value from one function call to the next.

The above 2 are the same as ANSI specs. The compiler also adds one called overlay, which is like static except you can reinitialize it each time the function is called. If you have "static int a = 1;" in a function, a is only given the value 1 when it is declared, and not every time the function is called. "overlay int a = 1;" will set a to 1 each time. There is more stuff on overlay in MPLAB-C18-Users-Guide.pdf. Note that overlay cannot be used in functions called recursively (from the docs).