Embedded Systems Architecture

Shared libraries

Suppose that there is a small library providing general-purpose utilities or device drivers, which is in use by both the bootloader and the application. Even when the footprint is small, it is preferable not to have duplicate definitions of the same functions in the flash memory. The library can instead be linked in a dedicated section of the bootloader, and referred to in a later stage. In our preceding two-stage example, we can safely place the API function pointers in an array starting at address 0x400, which is past the end of the interrupt vector we are currently using. In a real project, the offset must be high enough to be after the actual vector table in memory. The .utils section is placed in the linker script in ...