NAME
    ReadExpansionByte - read a byte nybble by nybble.

SYNOPSIS
    byte = ReadExpansionByte( board, offset )
    D0                        A0     D0

FUNCTION
    (Not typically called by user code)

    ReadExpansionByte reads a byte from a new-style expansion
    board.  These boards have their readable data organized
    as a series of nybbles in memory.  This routine reads
    two nybbles and returns the byte value.

    In general, this routine will only be called by ReadExpansionRom.

    The offset is a byte offset, as if into a ExpansionRom structure.
    The actual memory address read will be four times larger.
    The macros EROFFSET and ECOFFSET are provided to help get
    these offsets from C.

INPUTS
    board - a pointer to the base of a new style expansion board.
    offset - a logical offset from the board base

RESULTS
    byte - a byte of data from the expansion board.

EXAMPLES
    byte = ReadExpansionByte( cd->BoardAddr, EROFFSET( er_Type ) );
    ints = ReadExpansionByte( cd->BoardAddr, ECOFFSET( ec_Interrupt ) );

SEE ALSO
    WriteExpansionByte, ReadExpansionRom