This manual includes hardware details and programming information for the MC68HC000, the MC68HC001, the MC68EC000, and the MC68SEC000. For ease of reading, the name M68000 MPUs will be used when referring to all processors. Refer to M68000PM/AD, M68000 Programmers Reference Manual, for detailed information on the MC68000 instruction set.

The four microprocessors are very similar to each other and all contain the following features:
•  Sixteen 32-Bit Data and Address Registers
•  16-Mbyte Direct Addressing Range
•  Program Counter
•  6 Instruction Types
•  Operations on Five Main Data Types
•  Memory-Mapped Input/Output (I/O)
•  14 Addressing Modes
The following processors contain additional features:
•  MC68HC001/MC68EC000/MC68SEC000
— Statically selectable 8- or 16-bit data bus
•  MC68HC000/MC68EC000/MC68HC001/MC68SEC000
— Low power