Motorola 68010

It is largely similar to the Motorola 68000 CPU with the exception of the addition of several instructions for breakpoint[?] and register control, as well as the ability to save all of the processor state on an interrupt. This made it far easier to use for virtual memory applications, for which the 68000 was unsuited. The idea appears to have been to allow the 68010 to be used with the 68551[?] MMU, but problems with the design made this impractical. (like what?)

The 68010 was never as popular as the 68000 as the added complexity and cost turned out to not be worthwhile in practice. Most vendors looking for the MMU functionality waited for the 68020 instead. However due to a small speed boost over the 68000, it can be found in a number of Unix workstations and research machines. In addition, a special version was produced that was pin-compatible with the 68000, and was used in a number of Amiga machines in the 1980s.