I am resurecting an n gauge layout that has been dormant for about 15 years. I am trying to decide about switching over to dcc. The layout was set up with a single mainling but has a couple of passing sidings so that I could run trains in opposite directions and just put one on a passing siding and cut the power off when I wanted to have one pass. In dcc, is it still possible to have engines running in the opposite direction? or do you have to make special provisions???