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Grub multiboot framebuffer_bpp value
https://forum.osdev.org/viewtopic.php?f=1&t=33832
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Author:  tommasop [ Fri Aug 16, 2019 6:14 am ]
Post subject:  Grub multiboot framebuffer_bpp value

Hi, i don't really understand the value inside framebuffer_bpp in the multiboot info. For every video mode i set the bpp in this field are always different from the one i specified in the header. To make an example:
When i set video mode 1024*768 32bpp, in the multiboot i find 20bpp, at first i tought that maybe the problem was how i wrote pixels on screen, so i tried different colors but they all seems right so i suppose the bpp really are 32 and not 20. So why do grub tells me i have 20?
Thanks.

Author:  Octocontrabass [ Fri Aug 16, 2019 6:17 am ]
Post subject:  Re: Grub multiboot framebuffer_bpp value

Are you sure that's 20 and not 0x20? (0x20 is 32)

Other than that, maybe there's a problem with how you're reading the multiboot info.

Author:  tommasop [ Fri Aug 16, 2019 6:21 am ]
Post subject:  Re: Grub multiboot framebuffer_bpp value

Octocontrabass wrote:
Are you sure that's 20 and not 0x20? (0x20 is 32)

Other than that, maybe there's a problem with how you're reading the multiboot info.


Damn, you're right, thanks. I'm such an idiot...

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