I'm trying to cause a circle drawn in an IMAQ image field to grow for however long the mouse button is held down over the field, then persist at the last size once the mouse button is released. So far all parts of this work except for the circle growing while the mouse is held down. (The function is just supposed to iterate a value for the x,y parameters for the bounding box of the circle). LabView picks up on the Mouse Down event once, then the Mouse up event once, no matter how long I hold down the mouse button. Is there a way to repeatedly trigger an event for Mouse Down while it's being held down (and not clicked repeatedly)? Extra sweet if I can time delay the event trigger rate (say, once every 10ms) without tying up the CPU in wait mode.