How to initialize global variables using CCS

You have to clear memory with a user function.  Use something like this:

int _system_pre_init( void )
/**
 * Set RAM to zero.
 * This is a lowlevel initialization routine of the runtime!
 *
 * \note
 *    the runtime of the CCE20 does not do that on its own!
 */
{
   extern uint8_t __bss__;
   extern uint8_t _stack;

   // turn watchdog off
   watchdog_init();

   //lint -e(946)
   memset( &__bss__, 0, &_stack - &__bss__ );
   //lint -e(419)
   memset( &_stack, LOW_STACK_PATTERN, MM_STACKSIZE - 32 );
   return 1;
}   // _system_pre_init

Hardy

If you don't initialize global variables with a definition and just declare them, I'm not sure whether the standard defines a pre-initialization with 0. It is usually done, but I don't think it is a neccessity by the C standard. So it works only coincidentally, based on the compiler.

So if you have a global variable X then do not just declare it with e.g. unsigned char X; but do define it in one of the code files with unsigned char X = 0; Then it will (must) be initialized. It depends on the compiler whether this variable will initialized by copying the 0 from the init data flash area or placing it in an area which is initialized with 0 with a code loop.

My guess is that you might be able to force CCS to init the variables by either putting them all into a segment that is initialized (but then you can as well just define an init value to them) or maybe by altering the linker scripts, so the linker will consider all uninitialized variables to fall into an initialized data segment rather than an uninitialized.

Unfortunately, I don't know the CCS linker scrips well enough to tell you how this might work.