Here's a quickie user interrupt demo program I wrote. testint installs it, and remove uninstalls it when you get pissed at it. :) Oh yeah, if you use jmv or memedit or something and set bytes at C408 and C409 to 0 it uninstalls any user fonts, interrupt routines, etc. Good for killing off the tidemo prog. and stuff like that without taking out the batteries. --Joshua