NAME
        ReadCardStatus -- read credit card status register

   SYNOPSIS
        status=ReadCardStatus()
        d0

        ubyte readcardstatus( void );

   FUNCTION
        Returns current state of the credit card status register.

        See card.h/i for bit definitions.

        Note that the meaning of the returned status bits may vary
        depending on the type of card inserted in the slot, and
        mode of operation.  Interpretation of the bits is left
        up to the application.

   RETURNS
        A ubyte value to be interpreted as status bits.

   NOTES
        This function may be called from within a task, or from any level
        interrupt.

   SEE ALSO
        resources/card.h, resources/card.i