Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [embedded]

The use of Unix in embedded computer systems such as networking equipment, mobile phones, media players, set-top boxes, etc.

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Why does sh say "not found" when it's definitely there?

Possible Duplicate: “No such file or directory” lies on Optware installed binaries I'm trying to add ebtables to a little router box. I went and got a binary compiled for the correct architecture, and put it on the box in /sbin/. When I do…
Shawn J. Goff
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Corruption-proof SD card filesystem for embedded Linux?

Recently we had a rather unpleasant situation with our customer - Raspberry Pi based "kiosk" used to display remote sensing data (nothing more fancy than a kiosk mode browser displaying a self-updating webpage from the data-collection server) failed…
SF.
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How to check password with Linux?

I want to check, from the linux command line, if a given cleartext password is the same of a crypted password on a /etc/shadow (I need this to authenticate web users. I'm running an embedded linux.) I have access to the /etc/shadow file itself.
michelemarcon
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Mount zip file as a read-only filesystem

I am looking for a way to mount a ZIP archive as a filesystem so that I can transparently access files within the archive. I only need read access -- the ZIP will not be modified. RAM consumption is important since this is for a (resource…
Grodriguez
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How to extract files from uImage?

Buildroot is generating images for an embedded device where they should run. This is working very well. In those images, the rootfs is included. Due to some research, I'd like to look into that generated file (e.g. different compression modes set by…
user3085931
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Why do embedded systems need device tree while pcs don't?

When booting a kernel in an embedded device, you need to supply a device tree to the Linux kernel, while booting a kernel on a regular x86 pc doesn't require a device tree -- why? As I understand, on an x86 pc the kernel "probes" for hardware…
MOHAMMAD RASIM
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How to list the kernel Device Tree

I am using an embedded Arm with a Debian build. How does one list the compiled devices from the device tree? I want to see if a device is already supported. For those reading this, the "Device Tree" is a specification/standard for adding devices to…
Xofo
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Can I achieve functionality similar to interrupts in Linux userspace?

One of functionalities I miss the most from "small embedded" in Embedded Linux is the interrupts. A signal appears on a specific pin, or other interrupt source is triggered and whatever was done inside the CPU gets interrupted, and my function of…
SF.
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Attaching USB-Serial device with custom PID to ttyUSB0 on embedded

I'm attempting to get an FTDI USB-Serial device with a custom PID to automatically (or even manually) attach to ttyUSB%n, without much success. The device's normal VID/PID is 0403/6001. When programmed this way, it works perfectly and…
trycatch
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How do I have Linux boot with a rootfs in RAM?

The rootfs is a squashfs image and my bootloader is loading it into some address in SDRAM. What parameters do I need to pass to the kernel so It can mount the rootfs from there? Squashfs support is built-in and it already works…
Atilla Filiz
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Shell command to read device registers?

On a single-board computer running Linux, is there a way to read the contents of the device configuration registers that control hardware? I think it would be a wrapper for inw(). I'm looking for something equivalent to the U-boot memory dump (md)…
pingswept
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How can I observe memory bandwidth?

I have an embedded Linux ARM system that is showing significantly less throughput than expected on both Ethernet and USB. I suspect the memory may be contributing. Is there a way to observe the memory bandwidth that is consumed while running a…
Shawn J. Goff
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What are the minimum root filesystem applications that are required to fully boot linux?

It's a question about user space applications, but hear me out! Three "applications", so to speak, are required to boot a functional distribution of Linux: Bootloader - For embedded typically that's U-Boot, although not a hard requirement. Kernel -…
MDMoore313
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Is using a read only root file system a good idea for embedded setup?

I have been tasked with running Linux as an operating system on an embedded device. The target has an x86 processor and has 8 GB CompactFlash device for storage. I have managed to use buildroot to create the kernel image and cross compilation…
mathematician1975
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Is it possible for a daemon (i.e. background) process to look for key-presses from a USB keyboard?

I'm working on an embedded Linux project where I will be developing a program that will run automatically on bootup and interact with the user via a character display and some sort of button array. If we go with a simple GPIO button array, I can…
KyleL
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