NAME
        ReadBattMem -- read a bitstring from nonvolatile ram.  (v36)

   SYNOPSIS
        Error = ReadBattMem( Buffer, Offset, Len )
        D0                   A0      D0      D1

        ULONG ReadBattMem( aptr, ulong, ulong );

   FUNCTION
        read a bitstring from nonvolatile ram.

   INPUTS
        Buffer          Where to put the bitstring.
        Offset          Bit offset of first bit to read.
        Len             Length of bitstring to read.

   RESULTS
        Error           Zero if no error.

   NOTES
        The battery-backed memory is checksummed. If a checksum error
        is detected, all bits in the battery-backed memory are
        silently set to zero.

        Bits in the battery-backed memory that do not exist are read
        as zero.

        Partial byte reads (less than 8 bits) result in the bits read
        being put in the low-order bits of the destination byte.

   SEE ALSO

   BUGS