framebuffer bit depth

Felix Miata mrmazda at
Sat Nov 3 08:25:15 PDT 2007

On 2007/11/03 22:42 (GMT+0800) zhengyi apparently typed:

> IBM T30 laptop computer,
> I use kernel param vga=0317 to load kernel with framebuffer console 
> at resolution 1024x768 and the depth=16. The driver is vesafb in the
> kernel source package.

> If vga=0318 is set, the console refuse to show anything, but the 
> kernel can boot correctly ( I can login it with SSH ).

> But the KDE can run at a resolution of 1024x768 and with 32bit depth.
> when KDE run , it use Radeon driver( the one in the kernel source tree).
> Who can tell me why? Why I can't use 32bit depth in console?

> Suppose I have no enough Video memory, It is reasonable that the console
> refuse to display anything when vag=0318 is set at grub.conf.
> But why kde can run at a 32bit depth ?

> In KDE, i use pseudo tty, I check th /dev/fb0, and using some code 
> to test it.
> I found that by /dev/fb0, I can contol the top half of screen.

> What push me into fuzz is : when the system run KDE, why the /dev/fb0 
> not change to  enough size ?
Do you have some idea why you think you should have more than 8 bit color on
the consoles? I'm unaware of any console apps capable of using more than 16
colors. I find vga=0x317 or vga=0x314 more than adequate for any console apps
I've used.
"   A patriot without religion . . . is as great a
paradox, as an honest man without the fear of God."
	                             John Adams

 Team OS/2 ** Reg. Linux User #211409

Felix Miata  ***

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