Wow, Maybe the question was phrased incorrectly.

I now have an interrupt being fired by timer1 at approx. 1 second. I had to keep guessing at the value I loaded into the timer until I got close to what I needed.

I would rather understand the formula for determining how to get the proper value to load into the timer. Can anyone shed some light on this?

How to take the clock speed, determine the prescaler value, and the counts that need to be preloaded in order for the timer to overflow and cause an interrupt.