#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

typedef int16_t my_type;

my_type value = 0xFC7F;

int main(int argc, const char * argv[])
{
  printf("0x%" PRId16 "\n", value);
  printf("Type uses %lu bytes\n", sizeof(my_type));
  return 0;
}

0x-897
Type uses 2 bytes