Turtle Farm

local tArgs = { ... }
local wait_time = 30
local placed = false

if #tArgs > 0 then
  wait_time = tonumber(tArgs[1])
end

while true do
  sleep(wait_time)

  for d=1,4 do
    turtle.select(1)
    turtle.dig()

    placed = false
    for i=1,16 do
      turtle.select(i)
      if (not placed) then
        placed = turtle.place()
      end
      turtle.dropDown()
    end
    turtle.turnRight()
  end
end