Programming Embedded Systems in C and C++

102 Chapter 8: Operating Systems

Spanish farewell), which is an acronym for “A Decent Embedded Operating Sys-

tem.” I think that name really sums it up nicely. Yes, it is an embedded operating

system; but it is neither the best nor the worst in any regard. In all, there are less

than 1000 lines of source code. Of these, three quarters are platform-independent

and written in C++. The rest are hardware- or processor-specific and, therefore,

written in assembly language. In the discussion later, I will present and explain all

of the routines that are written in C++ along with the theory you need to under-

stand them. In the interest of clarity, I will not present the source code for the

assembly language routines. Instead, I will simply state their purpose and assume

that interested readers will download and examine that code on their own.

If you would like to use ADEOS (or a modified version of it) in your embedded

system, please feel free to do so. In fact, I would very much like to hear from any-

one who uses it. I have made every effort to test the code and improve upon the

weaknesses I have uncovered. However, I can make no guarantee that the code

presented in this chapter is useful for any purpose other than learning about oper-

ating systems. If you decide to use it anyway, please be prepared to spend some

amount of your time finding and fixing bugs in the operating system itself.

Tasks

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