From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frederic Marmond Subject: Re: Using framebuffer device under Linux Date: Tue, 18 Nov 2003 14:11:26 +0100 Sender: linux-assembly-owner@vger.kernel.org Message-ID: <3FBA1A7E.6010405@eprocess.fr> References: <3FBA137E.7000108@hotpop.com> Reply-To: fmarmond@eprocess.fr Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <3FBA137E.7000108@hotpop.com> List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Lawrence Cc: linux-assembly@vger.kernel.org (re)Hi Lawrence! ;) I don't know about the FB managment in linuxassembly, but here is some points you can have a look regarding FB: - kernel may have support for FB already compiled in (see the kernel .config, and check that FB_ options are correctly setted) - if kernel has the FB support, have a look at the kernel parameters (append="video=something" in your lilo.conf) - you can also have a look at /var/log/messages - to see if FB is already working, have a look at the '/proc' (mount /proc;cat /proc/fb) - to access FB, open/write to /dev/fb0 - to use kernel driver fb routines, use ioctl to /dev/fb0 - read documentation about the driver in /usr/src/linux/Documentation (if the kernel sources are installed, and if the kernel you run was compiled there) - you can use the VESA driver (less optimised than a specific FB driver, but often work). Use the "vga=mode" parameter in your lilo to activate it. To access the frame buffer as a large memory, you must use *mmap* in C. I don't know how it may be called in assembly under Linux, but this may be a start for you. mmap will be used to map the device /dev/fb0 into memory. So, you may access the FB with assembly mov, very easily, as a 'standard' memory region. Regards, Fred Lawrence wrote: >Hi All, > >I am planning to do graphic with asm under Linux without X11. I am try >to use framebuffer as the "drawing plane". > >I've reached the article entitled "Using the framebuffer device under >Linux" within http://linuxassembly.org and I've extracted and compiled >fb.n according to the instruction. However, when I run "fb" under the >console in RH9, I only got a refresh and then back to the text console. > >I've tried fb under the installation environment of Debian 3.0, with I >thought it is already in framebuffer mode, but still got a failure. > > >I've tried ald fb, but when it is going to switch to framebuffer mode, >Linux squeeze and I have to telnet into my linux box using another >machine and issue a reboot... > >I can successfully run "leaves" under a-linux however, but I don't know >how to put fb under a-linux so as to see if it works, as there seems no >way to mount a floppy or access ethernet under a-linux. > >Would anyone be so kind as to tell me how could I access linux >framebuffer correcely using assembly, or point me out the forgettable >steps in order to run 'fb' successfully? > >my 'nasm -r' command spit out: > >NASM version 0.98.22 compiled on Sep 19 2003 > >Thanks >Lawrence > > >- >To unsubscribe from this list: send the line "unsubscribe linux-assembly" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html > > >