# Assignment 4 for CSCI 255

## Due date

This assignment *must* be submitted
as a single file gcd.s
for Assignment 4
of the CSCI 255 section
on UNCA moodle
by 11:00 PM on Wednesday, 17 November.

## The task

Write *in PIC assembly language* the following recursive routine:

uint16 GCD(uint16 n, uint16 m) {
if (n==m)
return n ;
else if (n<m)
return GCD(m, n) ;
else
return GCD(n-m, m) ;
}

Also, write a little "main" program to call your GCD.

Your program should used the stack frame format discussed on
pages 192 to 196 and should have some strong similarities with
the `fib`

program of Figure 6.31.