Quarry Turtle (Computer Craft)

-- Code by Kaffefilter - 1/1-13
-- Quarry turtle
-- 10 by 10
-- Slot 1 er til kul
-- Slot 16 til Enderchest
function trip1()
   for i = 1, 10 do
      while not turtle.forward() do
         turtle.dig()
      end
   end
   turtle.turnLeft()
      while not turtle.forward() do
         turtle.dig()
      end
   turtle.turnLeft()
      for i = 1, 10 do
         while not turtle.forward() do
        turtle.dig()
         end
      end
   turtle.turnRight()
      while not turtle.forward() do
         turtle.dig()
      end
   turtle.turnRight()
      if turtle.getFuelLevel() <= 64 then
         turtle.select(1) -- Coal slot
     turtle.refuel(1)
      end
end

function trip2()
   for i = 1, 10 do
      while not turtle.forward() do
         turtle.dig()
      end
   end
   turtle.turnRight()
      while not turtle.forward() do
         turtle.dig()
      end
   turtle.turnRight()
      for i = 1, 10 do
         while not turtle.forward() do
        turtle.dig()
         end
      end
   turtle.turnLeft()
      while not turtle.forward() do
         turtle.dig()
      end
   turtle.turnLeft()
      if turtle.getFuelLevel() <= 64 then
         turtle.select(1) -- Coal slot
     turtle.refuel(1)
      end
end

print("How deep?")
print("Do note, each letter equals 2 blocks")
deep = read()
if turtle.getFuelLevel() <= 64 then
   turtle.select(1) -- Coal slot
   turtle.refuel(1)
end

for i = 1, deep do
   for i = 1, 5 do
      trip1()
   end
turtle.turnRight()
turtle.forward()
turtle.turnLeft()
turtle.digDown()
turtle.down()
   for i = 1, 5 do
      trip2()
   end
turtle.turnLeft()
turtle.forward()
turtle.turnRight()
turtle.digDown()
turtle.down()
turtle.select(16) -- Enderchest slot
turtle.placeUp()
   for i = 2, 15 do
      turtle.select(i)
      turtle.dropUp()
   end
turtle.select(16) -- Enderchest slot
turtle.digUp()
turtle.select(1) -- Coal slot
end
print("Fuel level is now: "..turtle.getFuelLevel())