Building and running the boot code
The example provided here is one of the simplest executable images that can be run on the target. To assemble, compile, and link everything together, we can use a simple makefile that automates all the steps and allows us to focus on our software life cycle.
When the image is ready, we can transfer it to the real target or alternatively, run it using an emulator.
The makefile
A very basic makefile to build our startup application describes the final target (image.bin) and the intermediate steps required to build it. Makefile syntax is, in general, very vast, and covering all the functions provided by Make is outside the scope of this book. However, the few concepts explained here should be sufficient to get up and running on automating the build process.
Defining the targets for our makefile, in this case, is quite simple. The startup.c source file, containing the IV, some exception handlers, and the main and the global variables we used...
