Someone asked me for pictures. Not only does it fly, but if you ask too much of it it crashes, too! http://www.ccwebster.net/robintim/cap_232/cap232.html -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Do you need to implement control loops in software? "Applied Control Theory for Embedded Systems" gives you just what it says. See details at http://www.wescottdesign.com/actfes/actfes.html