modem = peripheral.wrap("right")
modem.open(1024)
modem.open(2048)
function listen()
 event,modemside,senderch,replych,msg,senderdist = os.pullEvent("modem_message")
end

while true do
 listen()
 if senderch == 1024 and replych == 2048 and msg == "need power" then
  print("power was requested!")
  turtle.place()
  while true do
   listen()
   if senderch == 2048 and replych == 1024 and msg =="over" then
    print("power was cut")
    break
   end
  end
  turtle.dig()
 end
end
