Questions tagged [framebuffer]
related to Linux `fbdev` abstraction (a.k.a. Linux framebuffer), as well as to accessing the framebuffer (a part of video memory) in general
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Low resolution in the EFI/VGA early boot framebuffer/console (and in GRUB)
When I boot my Linux machine with UEFI and grub2, I get only few graphic modes (resolution modes) available. And both of them are really smaller than my monitor/screen. For example, the boot console ...
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How do I change the framebuffer resolution at runtime without legacy /dev/fb0?
I have a server in production which was booted with a 1080p widescreen monitor attached and it used that when it automatically selected that resolution for the console on boot. Currently, it is ...
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Color range for tty
THIS IS NOT A PROBLEM ABOUT XORG
I have a singleboard PC with Intel N100 with 2 HDMI ports.
When arch boots, the color range changes to limited after i915 takeing over the display from UEFI ...
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Xorg FBDEV refuses to use the specified framebuffer
I'm using Xorg with the FBDEV driver, configuration:
Section "Device"
Identifier "Device0"
Driver "fbdev"
Option "fbdev" "/dev/fb0"
...
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How to return to efifb without reboot (re activate vga console)?
When I boot my Linux machine, I have only efifb framebuffer device available at first:
[ 0.642906] efifb: probing for efifb
[ 0.642954] efifb: No BGRT, not showing boot graphics
[ 0.642957] ...
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Is it possible to get separate framebuffers for displays on Nouveau?
I'm using a simple Nvidia GPU (gt730) to run desktop system on a home server. I'm using nouveau as the GPU driver built-in on the 6.9 latest kernel.
I use FBDEV (on /dev/fb0) to run the X server. /dev/...
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How are framebuffers, graphics cards and window systems connected?
Loose TL;DR: is the framebuffer device still used in Linux today? If so, does (for example) the X window system first write to, say, /dev/fb0, and then to GPU, or does it write to GPU directly, ...
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Linux standalone OpenGL usage
I would like to ask what makes the Linux graphics stack tick and how it all works together.
So far I have understood that it works like this - the Linux kernel exposes GPU drivers through the DRM ...
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Boot linux in text mode and without framebuffer?
This used to be the default some years ago: Linux would boot up on a text console, 80x25 characters. I want to get back to that - this is for a number of servers that boot over the net (with PXE) - ...
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My embedded application doesn't receive keyboard events (Linux framebuffer/Qt+QML application/systemd service/VNC server)
I need to remotely control a Qt / QML application on an embedded ARM instrument. I intended to do that using VNC. This doesn't work. An USB keyboard plugged in the instrument doesn't work either.
NB: ...
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Booting with an NVIDIA GPU, but without nouveau
I am trying to boot a Linux system (Debian 11) with an NVIDIA GPU; I need to avoid loading the nouveau driver, which I can do if I include some options on the linux command line (in grub.cfg):
...
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How does this whole FrameBuffer, DRM, KMS stuff work in todays Linux / Kernel?
I'm confused about what is what nowadays with Linux and video support for the console interface vs X.
Do the /dev/fb* items only relate to the old original framebuffer support?
Does DRM create/support ...
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Display images using fbi on startup using systemd
I can successfully display images using the following command:
sudo fbi -T 1 /home/pi/photo-screen/photos/*.jpg -t 4
I now want to start a slide show of those pictures as soon as the Raspberry PI ...
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Cannot write to /dev/fb0 in systemd-nspawn container
I've created a systemd-nspawn container in which /dev/fb1 from the host is bound as /dev/fb0. I've set PrivateUsers=off in the .nspawn config file, and the file ownership and permissions of /dev/fb0 ...
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What is the definitive (and simplest) way to use fbi on Raspberry OS Buster to display images automatically on startup?
I have made all sorts of modifications to my ACLs and even created a photos.service that starts fbi, but it only starts, and displays 1 image before the screen goes blank.
I have other processes (web ...
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Which service creates /dev/fb0 node?
I want to update the console-setup.service to detect screen resolution using fbset -s and adjust console font size accordingly. For fbset, I need /dev/fb0 to be present, but I don't know which service ...
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Buildroot and framebuffer
I am very new to embedded programming so please have some understanding if i sound dumb.
Recently i have built a linux kernel using buildroot tool.
These are the commands i used:
make ...
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2
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How can I get the number bytes to write per row for FrameBuffer?
Goal: I'm writing a very simple image viewer for framebuffer /dev/fb0 (something like fbi).
Current state:
My software takes the pixel resolution from /sys/class/graphics/fb0/virtual_size (such as ...
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1
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TERM=fbterm causes box-drawing characters (by curses) get scrambled
I'm writing TUI software on fbterm using python-curses library.
To get full color in fbterm, I read it's man page and concluded I need to change environmental variable TERM to fbterm.
Man page: By ...
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Video rom part of iomem usage
Given some x86_64 linux stock kernel running one single GPU embedded into whatever pci-e extension board.
cat-ing /proc/iomem, I can realize that some space is reserved in RAM and associated to the ...
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Relationship between framebuffer and a tty
A framebuffer is a device file which allows for a simplified interface to the screen.
For example running the below code on a RaspberryPi with a HDMI display connected:
cat /dev/urandom > /dev/fb1
...
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How to stream the linux framebuffer as video over http
I have an embedded linux system (yocto based) with a framebuffer UI (no X11) and a running web server.
Now I'm asking how to "mirror" the screen contents to a web page. Think of it like a ...
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153
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Problems enabling HDMI screen framebuffer on startup for ts_calibrate
I'm running EGT on a SAMA5D4 Xplained board. It uses KMS for output to a HDMI screen. I've got a touchscreen that needs to be calibrated on the first use, I'm using ts_calibrate from tslib. I have a ...
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Debian text mode framebuffer issue - Kernel 5.14
I can't fix the startup issue I'm facing since I updated my Debian (bullseye) to backports distribution in order to get the Kernel 5.14
As per my researching it seems to be something related to the ...
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1
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765
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How do I write directly to video memory without xorg?
Kind of an odd question I know, but fifteen years ago I was able to use svgalib on some ancient version of Debian to draw directly to video memory without xorg.
To my dismay I see svgalib was pulled ...
- 487
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97
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Frame buffer driver(altfb) not working with a 24 bit display
I am developing an embedded Linux system with a 24 bit LCD display. I use terasic linux-socfpga to compile the kernel and I want to use the altfb driver to show the desktop in LCD. For that, I copied ...
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413
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Low-Latency method to read Xorg or DRM framebuffer
I am trying to build an application that can measure the latency/processing time of graphics frameworks on Linux.
My idea is to implement simple programs that react to an input event (e.g. mouse click)...
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650
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Got EOS from element "pipeline0" on gst fbdevsink
I'm trying to forward video file to the framebuffer on my device that has no X. I'm using gstreamer with fbdevsink plugin.
When I test it with
gst-launch-1.0 videotestsrc ! fbdevsink
it works ...
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Alpine Linux: Disable switching into framebuffer mode at boot?
We are installing a custom version of Alpine Linux on several embedded elderly PC. The monitor is connected using VGA and may not report the supported resolutions correctly, hence the GPU may choose ...
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qt5 program with "-platform linuxfb" does not reset framebuffer when crashing
We have a qt5 program running under Alpine Linux v3.14 which uses a fragile legacy library which may cause the entire program to crash. Alpine Linux switches to framebuffer mode during start up. We ...
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How to hide firmware logo in GRUB?
I disabled the hidden menu feature of GRUB on Fedora 34 Workstation, which hides GRUB menu and lets the vendor logo remain on the screen during GRUB operation.
$ sudo grub2-editenv - unset ...
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how to not stretch the 4:3 (1024x768) resolution on a wide monitor (1920x1080)?
I need this because my dell notebook video card is only not freezing if I use nomodeset on grub.
But then, I am limited to 4:3 resolutions (right?).
So, I am looking for a way to not stretch the ...
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Is it possible to configure GRUB to remove UEFI vendor logo faster during boot?
I appreciate the flicker free boot feature of Fedora. However, I am a disappointed customer of my laptop manufacturer. I would like to see less of its logo, so that I could dwell less on my regrets. ...
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Write on /dev/fb0 has no effect on GUI console
I run X in this way
/usr/bin/X vt07 -retro
to have the GUI on console 7 and the gray grid as background.
On console 1 I write
while [ 1 ] ; do cat /dev/random > /dev/fb0; done
and I see the ...
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hwinfo --framebuffer shows nothing, can't change grub resolution
I am using a Lenovo Yoga C940 15" with Fedora 34. It has a 4K screen with an nvidia gtx1650 mobile card and integrated intel graphics. I wanted to change the resolution of the GRUB menu because ...
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Is it possible to access the "frame buffer" so I can change the properties of each pixel?
I don't know if my question is technically correct. Here is what I want to do,
I'm running linux with xorg. The colors on my screen is way too dull. Its not my hardware because when I had windows my ...
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2
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4k
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How can I enable TTY console?
I'm running Linux (Debian 10) on a Chromebook (Eve) using a stock Chrome OS kernel (4.4.x) with minor modifications. Everything runs (mostly) fine except that TTY console cannot be accessed via Ctrl+...
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Can't clear /dev/fb0
I have one of those 7" HDMI diplays from eBay, driving it with a Q1900 board running Ubuntu 20. I can write to the display using fbi:
sudo fbi -a -T 1 --noverbose -d /dev/fb0 -t 5 --blend 1000 &...
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cannot run in framebuffer mode. Please specify busIDs
from my previous question empty screen after booting from live persistent usb, I am able after boot to access all files and folders, but the X-server is unable to load (so I get only to tty1). From ...
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Is it possible to run fb on one head and X on anohter, given one card connected to a TV and a monitor?
I would like to set up so that my computer's monitor is connected to it's VGA output, while having a framebuffer on the other head.
Both heads seem to share a card.
They work fine as part of the same ...
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704
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Initializing framebuffer device without udev
I am trying to reduce boot time in a Raspberry Pi 4 using Yocto Linux. The system uses SysV init.
There is psplash that uses framebuffer, and Qt application that uses DRM/eglfs, displayed ...
- 301
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130
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X writing top of screen to random parts of framebuffer - Xorg problem?
I have an ASUS laptop with an SIS graphics card. The default Xorg generated when I installed Debian (well, technically Raspbian Desktop) was at 640x480, yet it can easily do better as it's a 1280x800 ...
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Cannot run in framebuffer mode. error help
I'm using ParrotSec and the system I normally used gave an error last night and I could not solve it.
I start normally, then wait, but the KDE does not start and the screen remains black. I pressed ...
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551
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How do I allocate memory for a framebuffer loadable kernel module (linux)
I'm writing a 'fake' framebuffer device so I can use my e-reader as an external screen for my raspberry pi. The e-reader part is working fine (https://github.com/llandsmeer/inkvt), but now I want to ...
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3k
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Cannot force Debian to start in Framebuffer 640x480 resolution
In order to port an embedded project from an ARM target to Linux/x86, I have to create a Debian VM (I'm using Virtualbox right now) which starts in framebuffer mode with 640x480 resolution.
I used ...
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Debian10: No such file or directory: /dev/dri/card0
I'm installing Debian 10 but I cannot startx nor have a GUI. I think the problem is about some driver.
Here are the errors I've got in /var/log/Xorg.0.log :
[drm] Failed to open DRM device for pci:...
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3
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3k
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How to access and use Linux Frame Buffer without GTK?
I'd like to use /dev/fb0 or whichever other files are provided by the linux.
This in a system specific way as low as possible how to read/write/interpret those device files for GUI frame-buffer non-...
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Can gstreamer fbdevsink output to Xvfb virtual framebuffer? Which device to use?
I learned recently how to use Xvfb virtual Linux framebuffer:
https://www.raspberrypi.org/forums/viewtopic.php?f=66&t=261264
I want gstreamer fbdevsink output into a virtual framebuffer, but that ...
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1
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435
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Displaying a picture on the framebuffer while running a script created with dialog
I have setup scripts that use the dialog command. They are used to prepare embedded servers.
I'd like to display a picture on a edge while a dialog script is running. The problem is, that dialog by ...
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0
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784
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Xfbdev not found after including X (tinyx/kdrive) in Buildroot
I'm trying to add Xorg to an evaluation board for which I've already been provided with a working linux kernel. The evaluation board has an LCD display and I can confirm hardware & drivers are ...
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