The Free On-line Dictionary of Computing (30 December 2018):

Motorola 6800
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)