Turtle

local modem = peripheral.wrap("right")
modem.open(5)
while true do
    local event, modemSide , senderChannel, replyChannel, message, senderDistance = os.pullEvent("modem_message")
    local m = message
    turtle.refuel()
    if m == "start" then
        turtle.dig()
        turtle.forwards()
    elseif m == "stop" then
        lock = true
    end
end