Source : Free On-Line Dictionary of Computing

Motorola 6800
     
         A {microprocessor} released shortly after the
        {Intel 8080}, in about 1975.  It had 78 instructions,
        including the undocumented HCF ({Halt and Catch Fire}) bus
        test instruction.  The 6800 evolved into the {Motorola 6801}
        and 6803.
     
        The {6502} was based on the design of the 6800 but had one
        less data register and one more index register.
     
        (1994-10-31)