i have a vt pro bought about 10-12 years ago and it recently started displaying the countdown screen then "alt" would flash 5 times, the flash the "8" countdown screen and back to alt. r&r battery does nothing. buttons dont seem to do anything, except interrupt the sequence unless i hold the front button down and then hold the side button down as well. it then displays the "sn 002 399" and "r1a" (prolly the s/n and revision number. can i recover the computer. losing dive data is ok.