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VESA bios and VGA Bios are not the same !!

The only document you must refer for VBE is from VESA.org

gedd wrote:VESA bios and VGA Bios are not the same !!
The only document you must refer for VBE is from VESA.org

Wrong and wrong. That is, of course the VESA BIOS of a given video card resides in the BIOS of the video card's ROM, alongside with the legacy CGA/EGA/VGA BIOS, but it's not two separate entities. And yes, you must refer to that document, but we are talking here about the implementation of the VBE BIOS on VirtualPC. No document describes that (well, at least no document available to us).


JAL

Tomaka17 wrote:According to Ralf Brown's interrupts list, interrupt 0x6D is the video BIOS entry point for many video cards

Which seems to mean that the VBE is rejecting the call, thinking it's not for VESA but for the normal BIOS. The problem must be before the call.


JAL

jal wrote: but it's not two separate entities

Ok, but two distinct logical entities that what i mean.

jal wrote:but we are talking here about the implementation of the VBE BIOS on VirtualPC

Which is different from other yes ... each VBE implementation are ifferent. That's why a standard exist, to be able to use these implementation on the same way

I speak by experience, i have used VESA.org docs to implements VBE driver on Virtual PC.
And i thinks many people on this forums do it like me

I would assume the folks who develop VPC implemented a rather functioning emulation of the S3 Trio (just no 15 and 24-bit colour modes), so if that's a VBE-compliant card, there's the ticket.

gedd wrote:I speak by experience, i have used VESA.org docs to implements VBE driver on Virtual PC. And i thinks many people on this forums do it like me

Yes, that would be the right way to go. However, the OP has a bug somewhere (in his code, probably), and assuming he has read the VBE specs, the bug is possibly not directly linked to his VBE code (but could be, of course).


JAL