Memory areas provide your application with dynamic allocation of fixed sized memory blocks. Memory areas should be used in preference to the standard C library malloc and free functions if the calling task (or interrupt service routine) cannot block.

You allocate a memory area by declaring it as a C variable

    CTL_MEMORY_AREA_t m1;

A message queue is initialised using the ctl_memory_area_init function.

    unsigned mem[20];
    …
    ctl_message_queue_init(&m1, mem, 2, 10);

This example uses an 20 element array for the memory. The array is split into 10 blocks of each of which two words in size.

You can allocate a memory block from a memory area using the ctl_memory_area_allocate function. If the memory block cannot be allocated then zero is returned.

    unsigned *block = ctl_memory_area_allocate(&m1);
    if (block)
      // block has been allocated
    else
      // no block has been allocated

When you have finished with a memory block you should return it to the memory area from which it was allocated using ctl_memory_area_free:

    ctl_memory_area_free(&m1, block);