MineDown.lua

running = true
while running do
    success, data = turtle.inspectDown()
    if data.name ~= 'minecraft:bedrock' then
        breakDown()
    else
        running = false
    end
end

function breakDown ()
    turtle.digDown()
    turtle.down()
    turtle.dig()
    turtle.turnLeft()
    turtle.turnLeft()
    turtle.dig()
    turtle.turnLeft()
    turtle.turnLeft()
end