Programming Embedded Systems, 2nd Edition

Initialize the Hardware

The final step in getting to know your new hardware is to write some initialization software. This is your best opportunity to develop a close working relationship with the hardware, especially if you will be developing the remainder of the software in a high-level language.

During hardware initialization, it may be impossible to avoid using assembly language. However, after completing this step, you will be ready to begin writing small programs. ^[5]

Tip

If you are one of the first software engineers to work with a new board—especially a prototype—the hardware might not work as advertised. All processor-based boards require some amount of software testing to confirm the correctness of the hardware design and the proper functioning of the various peripherals. This puts you in an awkward position when something is not working properly. How do you know whether the hardware or your software is causing the problem? If you happen to be good with hardware or have access to a simulator, you might be able to construct some experiments to answer this question. Otherwise, you should probably ask a hardware engineer to join you in the lab for a joint debugging session.

The hardware initialization should be executed before the startup code described in Chapter 4. The code described there assumes that the hardware has already been initialized and concerns itself only with creating a proper runtime environment for high-level language programs. Figure 2-7 provides an overview ...