Unfortunately it's been a couple years since I touched flash, and while I've sort of kept up with things, I'm having trouble doing something the "Right" way.

I'm updating an old flash program of mine which timed a users reaction. The old way I did it was to crank up the framerate to 120 frames/second (the highest flash 5 could go) displaying the start graphic as close as possible to when I wanted (I really wanted 1/250 of a second accuracy) and on each onClipEvent(enterframe) check to see if the button had been pressed.

I remember reading somewhere a year or so ago about a newer actionscript command which would redraw the stage even in between frames, and thinking that would let me set the flash movie to a "sane" framerate and still keep the accuracy I was looking for. However I can't remember the name of the command, and searching everything I can think of has turned up nothing. What is the correct (or at least MX2004 and above) method of doing this?