On Sat, Oct 17, 2020 at 07:20:32PM +0200, Eric Auer wrote:

> It basically says there are many ways in which hardware or
> software could fail to handle the year, but you do not say
> WHICH of them affect YOU. In particular, you could give it
> a try and change that "19" to "20" in your CMOS memory :-)
> Maybe your BIOS just fails to store the changed values.
> 
> write register number to port 0x70
> read or write contents via port 0x71
> 
> register number 0x32 contains the century in BCD, e.g. 0x20
> register number 0x09 contains the year, e.g. 0x20 now ;-)
> 
> In some cases, the century might be in another register,
> so you should first check what the current contents are.
> 
> Note that OR-ing the register number with 0x80 blocks NMI
> and that immediately after port 0x70 access you should
> access port 0x71, but messing with year and century will
> probably be quite harmless and not time critical.

So I did the following using debug:

mov al,32
out 70,al
in  al,71
--> AX=0020
mov al,09
out 70,al
in  al,71
--> AX=0094

And indeed: "date" immediately after boot says "Oct 19, 2094"
-- 
regards,
Zbigniew


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