CardRand is old unmaintained code, it worked well at the time it was written but I've replaced it with something more stable, more maintainable and more widely usable. You can read more about it at the TokenTools repository.
You can read more about why CardRand is being deprecated here.
A simple wrapper around libopensc for retrieving random data from a smart card HWRNG and feeding it into the kernel random pool using an ioctl. This makes it available to any application using /dev/random