ComputerCraft NZ Branch mining

-- NZ miner

local function dforward()
  while turtle.detect() == true do
    turtle.dig()
        os.queueEvent("")
        coroutine.yield()
  end
  turtle.forward()
end

local function digUD()
  while turtle.detectUp() == true do
    turtle.digUp()
        os.queueEvent("")
        coroutine.yield()
  end
  turtle.digDown()
end

local function digShort()
  for toMove = 1,3 do
    dforward()
        digUD()
  end
end


local function digTunnel()
  for toMove = 1,6 do
    dforward()
        digUD()
  end
end

local function LorR( _x )
  if (math.fmod(_x,2) == 0) then
    turtle.turnRight()
  else
    turtle.turnLeft()
  end
end

local function makeCC()
  turtle.turnLeft()
  dforward()
  digUD()
  turtle.turnLeft()
  turtle.turnLeft()
  dforward()
  dforward()
  digUD()
  turtle.turnLeft()
  turtle.turnLeft()
  turtle.forward()
  turtle.turnRight()
end

-- main, assumed to be starting just outside of the area you want to mine
-- move forward for the starting leg
digShort()
-- setup the first crosscut
dforward()
digUD()
turtle.back()
-- face the correct direction
turtle.turnRight()

-- for now, 7 iterations deep.  That's a good starting point.
for x = 1,7 do
  for y = 1,x do
    -- already facing the correct direction.
        digTunnel()
        if (math.fmod(x,2) == 0) then
          if (y == (x/2)) then
            makeCC()
          elseif (y == math.floor(x/2)+1) then
            makeCC()
          end
        end
  end
  -- if X is even, turn right, forward, right.  Else turn left, forward, left
  LorR(x)
  digShort()
  LorR(x)
end