On desktop computers, the selection of an operating system (OS) is largely a matter of taste - Windows vs Apple vs Linux. There is relatively little choice. For an embedded system, the matter is much more complex. The large number of options available reflect the wide diversity of embedded applications.
Do you really need an OS?It is rare nowadays to find an embedded system without an OS. Only the simplest kind of device can be built efficiently without a kernel of some kind. But this possibility should not be dismissed. The whole spectrum of embedded devices can be represented by a chart (Figure 1) of CPU complexity – broadly, data bus width – against software complexity.
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