Cisco 831 router password recovery gone wrong

Hello,
I was trying to recover a password on a cisco router that I bought 2nd hand, I typed the command confreg 0x2120 instead of 0x2102 and from that time, all I see from the router is like the stuff what I pasted below, can I recover this router and is this stuff that I am seeing the router boots up?

??*]?W???r?5??QD?h,Y???988?o??(g???$??????? ??j??h????.(.?h?E?l:B?
???B??JJJi[??nN??j.E+!?*??E JJ?zi[??