5.5    68000 Instruction Set

The 68000 instruction set contains 56 basic instructions. Table 5.3 lists them in alphabetical order. Table 5.4 lists those affecting the condition codes. The repertoire is very versatile and offers an efficient means to handle high-level language data structures (such as arrays and linked lists). Note that in order to identify the operand size of an instruction, the following is placed after a 68000 mnemonic: .B for byte, .W or none for word, .L for long word. For example:

ADD.B       D0, D1   ;   [D1]8 ← [D0]8 + [D1]8

ADD.W or ADD   D0, D1   ;   [D1]16 ← [D0]16 + [D1]16

ADD.L       D0, D1   ;   [D1]32 ← [D0]32 + [D1]32

TABLE 5.3 68000 Instruction Set



Length (words)


ABCD − (Ay), ...

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