Turtle Redstone Elevator

-- set redstone back and left and right
-- back floor 1
-- right floor 2
function Menu()
	term.clear()
	local n=1
	while true do
		local x, y=term.getCursorPos()
		term.clearLine()
		if n==1 then write(">APPELER ASCENSEUR<   DESCENDRE") else write (" APPELER ASCENSEUR   >DESCENDRE<") end
		term.setCursorPos(x, y)
		a, b=os.pullEvent()
		while a~="key" do a, b=os.pullEvent() end
			if b==203 and n==2 then n=1 end
			if b==205 and n==1 then n=2 end
			if b==28 then print("") break end
		end
		if n==1 then
			redstone.setOutput("right", false)
			redstone.setOutput("back", true)
		end
		if n==2 then
			redstone.setOutput("back", false)
			redstone.setOutput("right", true)
		end
		return false

end


Menu()
os.sleep(6)
os.shutdown()