embedded-linux

I am trying to run Yocto Image in qemu on my Ubuntu laptop with the following command. qemu-system-arm -M overo -m 256 -sd ./test.img -clock unix -serial stdio -device usb-mouse -device usb-kbd Qemu works fine and the image is booted pretty clean, but I am unable to use my keyboard and Mouse. On any key press I get this warning. usb-kbd: warning: key event queue full Any workaround for this unresponsive keyboard? Zafrullah Syed The problem was, I need to specify USB bus number with device number for USB Pass-Through. Get the list of USB's by this command lsusb and it will list them as

I installed gcc-arm-linux-gnueabihf cross-compiler on Ubuntu 12.04, and now I am able to build a program for embedded device. Where can I find cross gdb for debugging? gcc-arm-linux-gnueabihf reference contains gdb-arm-linux-gnueabihf in the Related Packages list, which seems to be the debugger that I am looking for. But this package is not available. I recommend getting gdb from the Linaro toolchain rather than the Ubuntu repositories. Download gcc-linaro-arm-linux-gnueabihf-4.7-2012.10-20121022_linux.tar.bz2 from here and you'll find: bin/arm-linux-gnueabihf-gdb arm-linux-gnueabihf/debug

This one is a basic question related to u-boot. Why does the u-boot code relocate itself ? Ok, it makes sense if u-boot is executing from NOR-flash or boot ROM space but if it runs from SDRAM already why does it have to relocate itself once again ? Joe Kul This question comes up frequently. Good answers sometimes too. I agree it is handy to load the build to SDRAM during development. That works for me, I do it all the time. I have some special boot code in flash which does not enable MMU/cache. For my u-boot builds I switch CONFIG_SYS_TEXT_BASE between flash and ram builds. I run my

In embedded devices such as printer, switches, I am confused what the difference between the firmware and the operating system is. Are embedded devices operating systems similar to PCs (Linux and Windows)? For example, I have a printer which has an embedded web server that allows me to manage the printer remotely. When I open the manufacturer website, I find that the OS is: OS 9.86. What kind of OS is this? See: Phaser 8560 Support & Drivers JosephH Firmware refers to a small piece of code that resides in non-volatile memory. In hardware peripherals that are commonly found in offices these

I work with the Yocto Project quite a bit and a common challenge is determining why (or from what recipe) a file has been included on the rootfs. This is something that can hopefully be derived from the build system's environment, log & meta data. Ideally, a set of commands would allow linking a file back to a source (ie. recipe). My usual strategy is to perform searches on the meta data (e.g. grep -R filename ../layers/* ) and searches on the internet of said filenames to find clues of possible responsible recipes. However, this is not always very effective. In many cases, filenames are not

On my embedded system I usually use /dev/ttyS0 as a main console. This is achieved by passing kernel parameter console=/dev/ttyS0 and when init takes its part, getty is fired on the same device as specified in inittab by eg. ttyS0::respawn:/sbin/getty -L ttyS0 115200 vt100 . Is there any possibility to change these settings without restart and switch the console to another terminal like ttyS1 , ttyUSBx or even some pseudo tty? It seems that perhaps you don't actually want the console log messages on another device, but are only proposing to redirect them there to stop them from interfering

I can use hcitool lescan with the --duplicates flag to capture periodic LE Advertising Reports (proximity beacons) from two nearby BLE devices: $ sudo hcitool lescan --duplicates LE Scan ... C8:0F:10:29:4D:98 MI1S C8:0F:10:29:4E:75 MI1S C8:0F:10:29:4E:75 MI1S C8:0F:10:29:4D:98 MI1S C8:0F:10:29:4E:75 MI1S C8:0F:10:29:4D:98 MI1S <snip> Here is that scan again, with timestamps added to show the periodicity: $ sudo stdbuf -i0 -o0 -e0 hcitool lescan --duplicates | perl -nle 'print scalar(localtime), " ", $_' Wed Apr 13 13:46:45 2016 LE Scan ... Wed Apr 13 13:46:46 2016 C8:0F:10:29:4E:75 MI1S Wed

As discussed in this question, i am reserving a memory chunk at the boot time using a kernel boot parameter memmap=8G$64G I have written a character driver kernel module which , during initialization does a ioremap of this reserved memory chunk. As explained here , in my driver mmap all i need to do is remap_pfn_range for this memory chunk pointer returned by the ioremap . I am running this on 3.0 linux kernel . My user space application opens this memory chunk as a device mounted by the driver. When i do mmap from the use space application i see a system hang. my dmesg don't provide me much