Pic List, Is the internal osc. of the 12C508/9 stable and accurate enough for RS-232? It seems to work, but can I depend on it? Microchip says resonators are too variable for serial work, and so I have always used crystals. Is the internal osc on these chips stable enough for reliable indoor operation? Thanks, John __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com