I'm not sure if this is normal behavior, but when I spin my Happs 3" trackball in Centipede, Millipede and Missile Command (the only three games I tested) and then suddenly stop the trackball spin with my hand, the cursor moves an additional half an inch or so on the screen before coming to rest. (Note: the cursor is not backspinning).
Funny thing is, when I exit Mame and go into windows and try the same thing with the mouse pointer it stops on a dime when the trackball stops spinning.
Please try this on your cabinets, especially in Centipede and let me know if this is also happening to you. It might just be part of the game.
Let me know what you find out. If you do not encounter this condition, please provide the following details:
1. trackball type (Happs, suzo, etc.)
2. encoder brand (opti-pac, hagstrom, etc.)
3. OS (Win98, win2k, etc.)
4. Analog controls setting in mame: both speed and sensitivity.
Thanks everyone,
Marco