I tried searching, but the search page is busted.
Yesterday I tried setting the lock bits of my t2313 to 0xFC, zeroing LB1 and LB2. Avrdude wouldn't set the bits and just kept complaining that the verification didn't match. Then I just got desperate and tried changing them to anything, and they wouldn't change.
I changed lfuse earlier to the 8Mhz clock with no problems, but I just can't change the lock bits. I'm using a SPI programmer hooked up to my parallel port.
I see in the datasheet that lock bits may be set by serial programming mode, but that the last byte in the programming command is: 11iiiiii, where i are input bits. Does this partial byte throw off avrdude somehow? Have you guys set lock bits on the t2313 using avrdude?
Also, I've read online about a high voltage serial mode that can recover chips if the reset pin is disabled. I can't find anything in the datasheet about a high voltage serial mode, only a parallel one. Is there any truth to this?