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Hello fellow developers,

I've encountered a problem while getting time from CMOS in QEMU

The problem is converting BCD time to plain binary.

(bcd >> 1) + (bcd >> 3) + (bcd & 0xf), this doesn't work , optimized version doesn't work either.

Any help?

The problem is not related to QEMU, but to your BCD conversion formula. As pointed out in this post, it should be

((bcd & 0xF0) >> 1) + ((bcd & 0xF0) >> 3) + (bcd & 0x0F)

That didn't work either

You say it doesn't work. Mind describing how it doesn't work?

I am not an expert on this, but if the problem is that the time showing up isn't correct, are you even sure that QEMU has the right time in the CMOS?

Well if I display the time, seconds for example, as hexademical it shows the right time, when I use the code above it just shows some well, crap, pardon my French

This could have one of these reasons:

• The input data is not BCD coded.
• The number you get out of this formula is wrong (unlikely).
• The printf function for decimal numbers does not work properly.

Have you checked step by step whether any of these applies to your problem?

Print for numbers works, but I think that the format is not BCD coded, because the formula produces the wrong output >_>

This is a QEMU problem and has been fixed in version 0.14.