Common embedded system Linux, uClinux, WinCE, PalmOS, Symbian, eCos, uCOS-II, VxWorks, pSOS, Nucleus, ThreadX, Rtems, QNX, INTEGRITY, OSE, C Executive. .
In addition to real-time WinCE somewhat less, and most embedded real-time operating systems are very strong, so it can be called a real-time operating system Real Time Operating System. Embedded in the people required to master at least an embedded operating system (of course, master the better of the two), which is the most critical in the technology embedded in all. The most important RTOS include:
The first category, the traditional classical RTOS: the most important is Vxworks operating system, as well as its Tornado development platform. Vxworks because Earlier, strong real-time appearance (said to be in response to external events within 1ms request), and the kernel can be very slightly (reportedly minimum 8K), high reliability and so on, so in North America, Vxworks occupy embedded systems most Jiang Shan. Particularly at higher communication device like real-time systems, the non-Vxworks almost perfectly. Vxworks many of the concepts and technologies and Linux are similar, mainly C-language development. Like Bell- alcatel, Lucent, Huawei and other telecommunications companies in the development of products, Vxworks used a lot. But Vxworks due to high prices, so some small companies or small products often can not afford. At present, many companies are transferred to the embedded Linux (I heard that Huawei is currently so turn). Nevertheless, Vxworks over a period of time remains unshakable. And Vxworks slightly similar name as well as real-time operating system pSOS, QNX, Nucleus and other RTOS.
The second type, embedded Linux operating system: Linux's future except as a server operating system, is the most successful in the embedded field, because of course, is free, open-source, multi-support software, call owned by the public, so embedding type product cost will be lower. Linux itself is not an operating system designed for embedded, not micro-kernel, and real-time performance is not strong. Currently used in the field of embedded Linux system, there are two categories: one is the Linux system that has been cut off specifically for embedded designs, the most commonly used is uClinux (without MMU function), now account for a larger share of the application, can be run on the ARM7; the other is run on an ARM9, typically the Linux kernel 2.4.18 transplanted thereon, Linux can be used more features (of course more can be run on uClinux ARM9). Many people predicted that embedded Linux is expected to account for more than 50% share of the embedded operating system, is very important. The disadvantage is that too few people are familiar with Linux, developed slightly more difficult. At present, many textbooks and many universities to ucOS / II for teaching with real-time operating system, which is mainly due to ucOS / II is relatively simple, and open source, very suitable for beginners to learn real-time operating system works, but the disadvantage ucOS / II is limited functionality practical use less, so they should learn to direct practical learning, such as uClinux very practical. Moreover familiar with the Linux development, it is useful not only in the embedded field, to develop Linux applications for a better understanding of the operating system also helped, has multiple purposes. It is said that the current Intel, Philip are vigorously ARM + LINUX in embedded development, Fujitum is vigorously developing Linux on your processor. Currently in the field of embedded Linux, the following aspects are particularly hard to find people, one Linux can be ported to a new model of development version; the second is to write Linux drivers for the people; the third is familiar with the Linux kernel reduction and optimization of people.
The third category, WindowsCE embedded operating systems: Microsoft also seized a huge market embedded, WinCE out only a few years, but has now occupy a large market share, especially in the PDA, mobile phone, display instruments and other interface requirements or higher required for rapid development of applications, WinCE has been very popular (it is said that a sale of IPC board of the company selling good, as well as a chance for customers to reduce WinCE). WinCE mainly for version 4.2 (.NET), mainly as a development platform WinCE Platform Builder, sometimes some of the more developed the upper application with EVC environment, due to the WinCE development are familiar VC ++ environment, so learning Windows programming courses will not how much more difficult, and this is likely to be the cause WinCE accepted to facilitate the rapid development environment, Microsoft's strong technical support, well below the embedded WinCE difficult to develop Linux. For hurry to complete, do not want to take the adventure of embedded Linux developers occasions, WinCE is the most appropriate (find embedded Linux people can not so good looking), after all, the company did not try as students, to ensure the successful development is more important. The different focus, WinCE there are two special versions, one is dedicated to the MS PocketPC operating system on the PDA (PDA), and the other is a system for operating MSSmartPhone smart phones (mobile phone with PDA functionality), both also belong to WinCE platform. On the PDA and mobile phone market, in addition to WinCE, PDA famous embedded operating system as well as Palm OS (due to appear very early, very famous), Symbian, etc., but in the strong impact of WinCE, Palm and Symbian also to Japan how long? It was observed that, at present in the embedded platform, LINUX is the loudest, but still WinCE actual use even more. Embedded LINUX may be some more long-term product plans of the company, to reduce costs and carry out long-term consideration. WinCE and multimedia (such as MPEG technology) is one of Microsoft Asia Academy of Engineering currently doing more projects in the field, they need people proficient in WinCE.
