how to create cmos checksum error

Hot-swapping and Boot-Block flash & Boot block flash and floppy support
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snp
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Joined: Wed Jun 16, 2004 2:41 pm

Hello!

I've accidentaly flashed MVP3 BIOS into VP3. As the boards are similiar, PC booted up but ended POST on memory test without any possibility to enter BIOS setup. I've got two possibilities - hot flash or bootblock recovery. But the only way to start bootblock recovery is the CMOS checksum error, which is possible to happen when shorting chip pins (as the BIOS is OK to bootblock). I've got AT29C010 - which pins should I short to recieve chcecksum error and start bootblock?
edwin
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Got no other board to perform hotflash procedure then?
edwin/evasive

Do not assume anything

System error, strike any user to continue...
snp
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Posts: 2
Joined: Wed Jun 16, 2004 2:41 pm

It seems that hotflash is an obsolete solution and absolutly not needed. I've tried Rainbow's method of shorting two topmost address pins and it worked. i think, that 90% of hotflashed chips could be recovered by this method an it should be promoted as a first resort method.
PeteV
BIOS Rookie
Posts: 51
Joined: Wed Apr 07, 2004 8:22 am

Hi!

OK, I think you have solved the problem already, probably by shorting the pins 2 and 3, the next down from the marked pin 1.

Regards,

Pete V.
Rainbow
The UniFlasher
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The shorting method is NOT a replacement for hot-flash. It can be only used if the bootblock is not damaged and works on that board. There is also a risk of damaging the board. However, this method can be used even if the flash ROM is soldered to the board.
Patched and tested BIOSes are at http://wims.rainbow-software.org
UniFlash - Flash anything anywhere
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