Atmega8 lock bit setting issue

[ark5230]

In an attempt to get reliable firmware for 89S51/52 USBASP programmer I tried to copy hex file from a ready made programmer as I could not find what firmware to use from the thread
https://www.edaboard.com/threads/157151/
In that process I copied the lock bits also.
Later I realised that it might be locked for further use.
Now the question is that the Atmega8 which is programmed with lock bits 0xFC shown in attachment is there any chance of using this Atmega8 or it is lost and cant be used????

 

[alexan_e]

All it takes to clear the lock bits is a chip erase

The ATmega8 provides six Lock Bits which can be left unprogrammed (“1”) or can be pro-
grammed (“0”) to obtain the additional features listed in Table 86. The Lock Bits can only be
erased to “1” with the Chip Erase command.

 

[ark5230]

Thanks for the information.
I hope I can erase those bits by writing '1' using serial programmer.
I was worried as I had read some where on the forum regarding parallel erasing is only possible.
I will try this and hope it works.

 

[alexan_e]

you can't write 1 to the lock fuses that are set, you have to perform a chip erase and they will be cleared automatically, the flash will also be cleared.

 

[ark5230]

Yes true, I will do chip erase using serial programmer.
You are so specific and clear in guiding, you taught me many things here.
Thanks a lot. Please correct me if i am mistaken about clearing bits by chip erase!

 

[alexan_e]

you can only change the security fuses to a higher lock level when using individual fuse programming , not to a lower one
The security fuses are cleared after a chip erase, their purpose is to protect the flash content and after a chip erase everything is deleted so there is nothing to protect.