A microcontroller family from Motorola descended from the Motorola 6800 microprocessor.
The 68HC11 devices are more powerful and more expensive than the 68HC05 family.
There is an opcode simulator for the 68HC11, by Ted Dunning <email@example.com>. Interrupts, hardware I/O, and half carries are still outside the loop. Adding interrupts may require simulating at the clock phase level. Version 1.