Remote LED with erlang

net_led.erl

-module(net_led).
 
-export([start_light/0,  switch/2, light/1, decouple/1]).
 
decouple(Light_Node) ->
  {light, Light_Node} ! decouple,
  io:format("Switch is decoupled~n", []).
 
switch(Light_Node, Action) ->
  {light, Light_Node} ! {switch, self(), Action},
  receive
    Resp ->
      io:format("switch received response ~p ~n", [Resp])       
  end.

light(LedPin) ->
  receive
    {switch, Switch_PID, decouple} ->
      io:format("light decouple~n", []),
      LedPin ! stop,
      Switch_PID ! decoupled;
    {switch, Switch_PID, on} ->
      io:format("Light received on~n", []),
      LedPin ! on,
      Switch_PID ! on,
      light(LedPin);
    {switch, Switch_PID, off} ->
      io:format("Light received off~n", []),
      LedPin ! off,
      Switch_PID ! off,
      light(LedPin);
     {switch, Switch_PID, X} ->
       io:format("Unknown command ~p~n", [X]),
       Switch_PID ! error,
       light(LedPin)
    end.
 
start_light() ->
    LedPin = led:start(27),
    register(light, spawn(net_led, light, [LedPin])).