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Why my Vesa PM Info Block has the cheksum field filled with a 0 while the sum of the fields is 0xF8 Do your computers have the PM Info Block checksum properly filled?

Do Bochs/VirtualBox support Vesa?
Am I right I have to scan between 0xC0000 and 0xD0000 for the pm info block? The specs don't say that the block has to be 2-byte,4-byte,8-byte aligned etc. Does it mean I shouldn't assume it's 2-byte/etc aligned?

Adek336 wrote:Do Bochs/VirtualBox support Vesa?
Am I right I have to scan between 0xC0000 and 0xD0000 for the pm info block? The specs don't say that the block has to be 2-byte,4-byte,8-byte aligned etc. Does it mean I shouldn't assume it's 2-byte/etc aligned?

I think they support Vesa, but not the VBE3 Protected Mode interface. I wouldn't count on the PMID signature being aligned at all. I've found it at many different places.

Adek336 wrote:Why my Vesa PM Info Block has the cheksum field filled with a 0 while the sum of the fields is 0xF8 Do your computers have the PM Info Block checksum properly filled?

I find that the checksum value is wrong on many boxes - especially ones by Dell, yet they do _have_ a PMI Block. Not sure why they'd provide one but not give a checksum...

I think they support Vesa, but not the VBE3 Protected Mode interface.

That's too bad for them, they won't have the opportunity to run panaLiX It seems my Dell Latitude laptop with broken vbe3 checksum gets all the fun!

Vesa problem: I was aware my interrupt handling wasn't able to service interrupts while the kernel was executing the 16bit vbe-dedicated code segment descriptor selector, but only after 5 hours of stepping with BIOS code without a debugger I found out that two instructions before retf, BIOS does "sti" and a random timer interrupt unleashes hell I was so sure it wouldn't sti I didn't even check

I wish crashes would unleash shell

I am having some troubles with VBE on an ATI card.
I choose to use a mode, I get the mode-information block all right, resolution, physical base address is like 0xE8000000, I switch to the mode, the screen goes blank, I map the phys address in, fill it with data, nothing appears:(
Do I need some init before it draws to the screen like selecting the memory address of the first pixel which I think am doing with a 0x4F07 vbe call.

Adek336 wrote: Do I need some init before it draws to the screen like selecting the memory address of the first pixel which I think am doing with a 0x4F07 vbe call.

I don't think that is needed but I don't actually know. You could try to set the start offset to 0 just to check.