How can I implement an attract loop without a show controller?
You can use a looping playlist that contains the attract loop followed by your main show. The playlist would look like this:
L1, U, 2, I, ;
In the above example, file 1 is the attract loop and file 2 is the main show video. Your trigger can simply close a contact on the play input of the discrete control connector. Each time the trigger is hit (maybe by a motion detector) during the attract loop, the playlist will advance to the main show video. The U and I surrounding the main show entry ensure that the show itself cannot be interrupted by the trigger. Be sure to number your playlist 0 so the attract loop will start when you turn on the DVM2. You can learn more about the power of playlists in the http://www.alcorn.com/products/dvm2/manual.html]DVM2 manual.