Linux on embedded systems
Operating systems based on Linux kernel are used in embedded systems — such as consumer electronics (i.e. set-top boxes, smart TVs, in-vehicle infotainment (IVI), networking equipment (such as wireless routers), machine control, industrial automation, navigation equipment, spacecraft flight software, and medical instruments in general.
Thanks to their nature of versatility, operating systems based the Linux kernel can be also found in mobile devices that are actually touchscreen-based embedded devices — such as smartphones and tablets, together with personal digital assistants (PDAs) and portable media players that also include a touchscreen.
Linux kernel has been ported to a variety of CPUs which are not only primarily used as the processor of a desktop or server computer, but also ARM, AVR32, ETRAX CRIS, FR-V, H8300, IP7000, m68k, MIPS, mn10300, PowerPC, SuperH, and Xtensa processors. Linux is also used as an alternative to using a proprietary operating system and its associated toolchain.
Due to its low cost and ease of customization, Linux has been shipped in many consumer devices. Devices covering PDAs (like the Sharp Zaurus family), TomTom GPS navigation devices, residential gateways like the Linksys WRT54G series or smartphones such as the Motorola exz series, Openmoko handsets, and the Nokia N900 and Nokia N9.
A Linux kernel–based operating system known as Android, developed by Google, has become a highly competitive platform for smartphones and tablets. First introduced in 2008, in July 2012, Android's smartphone market share in the United States was 52%.
With the availability of consumer embedded devices, communities of users and developers were formed around theses devices: Replacement or enhancements of the Linux distribution shipped on the device has often been made possible thanks to availability of the source code and to the communities surrounding the devices. Due to the high number of devices, standardized build systems have appeared like OpenEmbedded, Buildroot, OpenWrt, and LTIB.
The advantages of embedded Linux over proprietary embedded operating systems include multiple suppliers for software, development and support; no royalties or licensing fees; a stable kernel; the ability to read, modify and redistribute the source code. The technical disadvantages include a comparatively large memory footprint (kernel and root filesystem); complexities of user mode and kernel mode memory access; and a complex device drivers framework.
Career opportunities for embedded software developers are also to be considered. When an embedded software development effort is completed, the developers often need to find another job. On 13 November 2013, an online search for jobs in Los Angeles for "VxWorks programmer" found zero job openings, whereas a search for "Linux kernel programmer" found 12 job openings, with annual salaries of $80,000 to $140,000.
- "Migrating VxWorks applications to Linux" (PDF). Monta Vista Software. 2008. Retrieved 2013-11-13.
- Fingas, Jon (2012-09-04). "ComScore: Android tops 52 percent of US smartphone share, iPhone cracks the 33 percent mark". Engadget.com. Retrieved 2012-11-24.
- Weinberg, Bill (July 2008). Uniting Mobile Linux Application Platforms. LinuxPundit.com. p. 18.
- Embedded Linux at the Open Directory Project
- "News and technical articles concerning embedded Linux". Archived from the original on 3 January 2013.
- Embedded Linux mailist list archive
- Complete Embedded Linux system in RJ-45
- Embedded Debian Project
- VxWorks to Embedded Linux: a Success Story