Your'e right Dave ( of course !!)
TTL is fitted to the cards in the Trinity Pro, Matrix Pro and Horizon models, as they all have beam table options with gratings etc..
I have a couple of units with this in . When the Cyphrlite software picks up the TTL on the FB3 , it loads the extra module in the software. It alows you to directly access each actuator and diff. wheels as well a program beam chases for bouncing.
If I have one in stock, I'll bring one to the next UK meet, for anyone who wants to play
Regards
Fluff