1. An improved microcontroller for use in an emulation circuit that externally controls execution of instructions by said microcontroller, said microcontroller having a CPU and internal memory and providing no direct external access to internal buses connecting said CPU and internal memory and wherein said microcontroller has at least two externally controlled alternative circuit configurations, one of said alternative circuit configurations including said internal memory and another one of said alternative circuit configurations not including said internal memory, said microcontroller also having a sleep mode of operation and at least one non-sleep mode of operation, said microcontroller further operating in accordance with a series of machine cycles each comprising a plurality of machine states, said improved microcontroller comprising: means for outputting on a dedicated first pin of said microcontroller, whenever said microcontroller is not in said sleep mode, a first pulse occurring once each machine cycle and synchronized with a predetermined single one of said machine states of each said machine cycle for use by said emulation circuit to synchronize said emulation circuit with each of said machine cycles of said microcontroller; and means for outputting on a dedicated second pin of said microcontroller, whenever said microcontroller is not in said sleep mode, a second pulse occurring once each machine state and synchronized with each of said machine states of each said machine cycle for use by said emulation circuit to synchronize said emulation circuit with each of said machine states of said microcontroller.