about frame buffer

yugandhar · 06-02-2006, 03:38 AM

Hi,
I write a program to test the frame buffer but by program is not working because /dev/fb0 is not there in /dev then i created /dev/fb0 using mknod but that too is not working
what i feel is while creating /dev/fb0 you have to know both major and minor number i know only major number from /proc where can i get minor number could you guys please help.

i am using fedora core 2.6.9 kernel. Also just me that it is right to test the framebuffer or not.

juanbobo · 06-02-2006, 03:39 AM

It probably needs to be enabled in your kernel.

jayjwa · 06-03-2006, 05:07 PM

I usually look in devices.txt in the kernel Docs for these numbers. I have this, althought the fb0 one is the only one I've actually seen in use.

Code:

crw-rw-rw- 1 root tty 29, 0 2002-04-16 00:49 /dev/fb0
crw-rw---- 1 root tty 29, 1 2002-04-16 00:49 /dev/fb1
crw-rw---- 1 root tty 29, 2 2002-04-16 00:49 /dev/fb2
crw-rw---- 1 root tty 29, 3 2002-04-16 00:49 /dev/fb3
crw-rw---- 1 root tty 29, 4 2002-04-16 00:49 /dev/fb4
crw-rw---- 1 root tty 29, 5 2002-04-16 00:49 /dev/fb5
crw-rw---- 1 root tty 29, 6 2002-04-16 00:49 /dev/fb6
crw-rw---- 1 root tty 29, 7 2002-04-16 00:49 /dev/fb7
crw-rw---- 1 root tty 29, 8 2002-04-16 00:49 /dev/fb8
crw-rw---- 1 root tty 29, 9 2002-04-16 00:49 /dev/fb9

And you're right, it does need to be added in-kernel, and for your specific video card as well.

CONFIG_FB=y
CONFIG_FB_CFB_FILLRECT=y
CONFIG_FB_CFB_COPYAREA=y
CONFIG_FB_CFB_IMAGEBLIT=y
CONFIG_FB_MODE_HELPERS=y
CONFIG_FB_VESA=y
CONFIG_FB_INTEL=y

The framebuffer is nice when you don't want to fire up X11 for every little thing. I've had Xine, Links, w3m, and a little viewer called 'fbv' all running on it.