Restore BIOS to factory settings using programming

[p***@nospicedham.gmail.com]

Hello,
I`m beginner assambly programmer.I would like to know how to restore BIOS to factory settings using programming. I read the forums and try to find a solution, unfortunately unsuccessfully.
Has anyone from this forum ever done anything like that? Maybe it is possible to simulate "no CMOS batteries"? And this way you can restore BIOS? I would like to know how to program it.

[wolfgang kern]

Post by p***@nospicedham.gmail.com
Hello,
I`m beginner assambly programmer.I would like to know how to restore BIOS to factory settings using programming. I read the forums and try to find a solution, unfortunately unsuccessfully.

there are tiny buttons on recent motherboards:"RESET/CMOS-CLR".
older PCs had a jumper near the CMOS battery (lift it for a second).
very old machines need a temporary remove of the battery.

Post by p***@nospicedham.gmail.com
Has anyone from this forum ever done anything like that? Maybe it is possible to simulate "no CMOS batteries"? And this way you can restore BIOS? I would like to know how to program it.

I haven't seen any software simulation for this, and I hope hardware
remain stubborn on this matter in future too.

There are (device-specific) bits in the flash-ROM control-port which
could be connected to a (fictive yet) CMOS=RESET-gate.

But it may be good advice to not play around with the Flash-Rom as long
you're not absolutely sure to know all details about your hardware.
__
wolfgang

[JJ]

Post by p***@nospicedham.gmail.com
Hello,
I`m beginner assambly programmer.I would like to know how to restore BIOS to factory settings using programming. I read the forums and try to find a solution, unfortunately unsuccessfully.
Has anyone from this forum ever done anything like that? Maybe it is possible to simulate "no CMOS batteries"? And this way you can restore BIOS? I would like to know how to program it.

Zeroing CMOS' standard checksum (and extended checksum) will basically
invalidate the CMOS data. After a cold boot, the BIOS will complain about
CMOS checksum error, which in turns will reset all BIOS settings to factory
default.

[R.Wieser]

Persky,

Post by p***@nospicedham.gmail.com
I would like to know how to restore BIOS to factory settings
using programming

Erase the contents of the CMOS chip. Next time you boot the 'puter will
complain about the setup info being damaged and load its defaults (you can
also force the 'puter to reboot afterwards ofcourse).

Though I hope you do realize that going back to "factory settings" doesn't
mean your computer will always be in a runnable state (just imagine using a
USB keyboard on a bios which does not have "legacy devices" enabled by
default), or that that state is anywhere near optimum (like having (very)
slow settings for memory speed).

In other words: chances are that you will still need to modify the BIOS
setup settings after rebooting, making a reset-by-program much less usefull.

Regards,
Rudy Wieser