In message , Cast_Iron
writes
And if your going into the
city its pointless having semi-fast services as a stopping service
comes in and you don't know whether when (or IF) the semi-fast service
is coming so you either let it go only to have the next train a
stopping service. Or get on the stopping service to have a semi-fast
speed past you at Northwick Park

And it is that very complexity which makes installation at such a place more
difficult to achieve successfully.

Perhaps what they need is a database showing the expected times of the
trains, and run the displays from that. You could call it a time
"table". Nah, it would never work.
--
Roland Perry