Posted by Jonathan Stanley on 8, 2000 at 3:31 AM:
I use my own frontend program that I have written that waits for the user to select a game before launching MAME (DOS). I was thinking how in my program I could easily toggle one of the keyboard LED's ON/OFF. What I'd like to do is have the LED cause a 12V "police" light or 12V strobe light mounted on the top of my cabinet to "light up". So if nobody had played anything in like 15 minutes I would make the (for example) CAPS LOCK key light up for 30 seconds thus causing the cabinet mounted light to come on and then turn off after the 30 seconds expires.
So what I'm thinking is I need some sort of relay to do this but I don't know what. I'd like something I don't have to mail order (Radio Shack???) One thing I have that might make this project easier is the IPAC keyboard encoder which has the optional LED controller so maybe I could wire it in from there - or perhaps just wire the relay (if that's what I should be using) directly to the appropriate LED controller pins on the IPAC board and not even need the LED controller??
I would imagine this same idea could also be used for other possible purposes such as activating a powered ticket dispenser or credit counter for custom applications. Toggle the CAPS LOCK light on/off = dispense a ticket/add a credit.
Thanks for your ideas!