Combinational versus sequential logic

• Combinational means no memory

  • Outputs depend only on the present inputs
    • Apply new inputs A, B
    • Wait for delay through logic
    • Observe C
    • C depends only on the current inputs

• Sequential logic has memory

  • Output also depends on previous inputs
    • Apply new inputs A, B
    • Observe C
    • Apply new inputs A, B later
    • C may now be different
    • Logic can remember previous inputs

B

A

C

B

A

C

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