void * p = (void *)0x28ff44;
Or if you want it as a
char * p = (char *)0x28ff44;
If you’re pointing to something you really, really aren’t meant to change, add a
const void * p = (const void *)0x28ff44; const char * p = (const char *)0x28ff44;
…since I figure this must be some kind of “well-known address” and those are typically (though by no means always) read-only.