This paper presents expectations, results, and comments on a project that used the N. mPc register transfer simulation package as a functional simulator to develop models for the MC68000 and MC68010. Several models that were developed to help determine both advantages and disadvantages of various levels of ~unctionality are described. It is shown that ~unctional level simulations do indeed serve a valuable purpose in the design cgcle as an additional, although by no means the only, tool ~or system level design verification.