Internal static variables in C, would you use them?

Question

In C you can have external static variables that are viewable every where in the file, while internal static variables are only visible in the function but is persistent

Answer 1

In writing code for a microcontroller I would use a local static variable to hold the value of a sub-state for a particular function. For instance if I had an I2C handler that was called every time main() ran then it would have its own internal state held in a static local variable. Then every time it was called it would check what state it was in and process I/O accordingly (push bits onto output pins, pull up a line, etc).