Option #1: You try to figure it out by yourself. Hours, days, months, weeks, loss of hair, new keyboard, etc, etc,...

Option #2 You rely on our resident genius to have already done it for you..;o}

Link to option #2. http://www.picbasic.co.uk/forum/showthread.php?t=1942

It may not be a full working code snippet for your specific application, but the
answer is there...;o}