Interrupt Question

I am fairly new to arduino and am wondering what is the best way to setup a 1 mSec tick? I really want to do this outside of loop() in more of an interrupt context.

I have spent a lot of timing developing a kernel and would like to reuse some of my work now that I have switched a arduino platform do to cheap hardware and free dev tools.

The built in functions millis() and micros() contain the milliseconds and microseconds since reset and can be accessed for timing purposes. See the "blink witout delay" example in the digital examples in the IDE. You can set up a timer to generate an interrupt every millisecond. Depends on what you are doing, which is the best.

See http://www.gammon.com.au/timers

On that page is code to generate an interrupt every mS.