Controlling model tram

[anon57585045]

@michaelasc

I need to be able to turn the power on and off in all four blocks.

Blocks two and three always have the same direction but they need to be energized and connected to the power from blocks one and four at different times, such that for the first part of the run, blocks one and and three; and blocks two and four are connected to each other; then this switches such that blocks one and two, and blocks three and four are connected to each other.

How can I set this? Do I need another logic gate of some sort?

You could just use some relays for that.