[jacquesgt]

There's a large block of memory that's easy to slice up on your own. It's called the BSS section, which is where global and static variables without an initial value are stored. BSS gets zeroed before main() is called.

This isn't possible in all cases, but for embedded software especially it's often possible to create all data structures as global or static variables. The compiler takes care of alignment concerns for you, and you're guaranteed not to have heap issues because you never use the heap. Of course, you can run out of the objects you pre-allocated in BSS, but that's an easier problem to diagnose and fix.