# Sensing more than one train on same track



## rva1945 (Feb 11, 2016)

Hi:

I built a couple of IR sensors that detect the arrival of the train so the microcontroller knows it has to gradually decrease the train speed to a halt.

But if I let two trains on the same track (DCC), how do I tell which train is detected? I want that train to stop, not the other one!

Thanks.


----------



## DonR (Oct 18, 2012)

Most do it using a block system and signalling which
can then be fed to your computer for control.

But it occurred to me that using the new RFi (?)
chips attached to the loco, each with a different
ID. (I'm way over my pay scale on this).

Don


----------



## dwagn (Mar 21, 2016)

I thought about using nfc tags once but figured that the delay in read time meant that the train would be long gone before the read completes.... So i didn't give it much thought.


----------

