down perfect

local tArgs = { ... }
if #tArgs ~= 3 then
  print( "Uso: down <largo> <ancho> <profundidad>" )
  return
end

local largo = tonumber( tArgs[1] ) - 2
local ancho = tonumber( tArgs[2] ) - 1
local profundidad = tonumber( tArgs[3] )
local pos = 1
local count = 0

function checkFuel()
  if turtle.getFuelLevel() < 20 then
    turtle.select(1)
    turtle.refuel(1)
    print("Refuelling")
  else
    print("No fuel necessary")
  end
end

function start()
  turtle.digDown()
  turtle.down()
end

function forward()
  while turtle.forward() == false do
    turtle.dig()
    turtle.attack()
    sleep(0.25)
  end
end

function back()
  while turtle.back() == false do
    turtle.turnLeft()
    turtle.turnLeft()
    turtle.dig()
    turtle.turnLeft()
    turtle.turnLeft()
    sleep(0.25)
  end
end

function up()
  while turtle.up() == false do
    turtle.digUp()
    turtle.attack()
    sleep(0.25)
  end
end

function down()
  while turtle.down() == false do
    turtle.digDown()
    turtle.attack()
    sleep(0.25)
  end
end

function avanzar()
  for i=0,largo do
    turtle.dig()
    forward()
  end
end

function torcer()
  if count == ancho + 1 then
    count = 0
  else
    if pos == 1 then
      turtle.turnLeft()
      forward()
      turtle.turnLeft()
      pos = 0
    else
      turtle.turnRight()
      forward()
      turtle.turnRight()
      pos = 1
    end
  end
end

function vuelta()
  turtle.turnLeft()
  turtle.turnLeft()
end

start()

  for i=0,ancho do
    avanzar()
    count = count + 1
    torcer()
  end

  if pos == 1 then
    turtle.turnRight()
    for i=0,ancho - 1 do
      forward()
    end
    turtle.turnRight()
    for i=0,largo do
      forward()
    end
    vuelta()
  else
    turtle.turnLeft()
    for i=0,ancho - 1 do
      forward()
    end
    turtle.turnLeft()

  end