Not even I know what it is for!

t = 0.5
while true do
    if rs.getInput("right", true) then
        rs.setOutput("back", false)
        sleep(t)
        rs.setOutput("top", true)
    else
        rs.setOutput("top", false)
        sleep(t)
        rs.setOutput("back", true)
    end
    sleep(t)
end