# Sequential Logic

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A **Sequential Logic** is a digital circuit where one or more outputs are boolean functions of multiple inputs and the history of the outputs. In contrast to combinatorial logic, a sequential logic requires memory to somehow feed the history of the outputs back to the inputs. Usually, for deterministic and reliable behavior considering internal latencies and propagation delays, a sequential logic is synchronous, that is the memory only change their content on the edge of a clock signal.

## Contents

# Applications

Sequential logic, that is combinatorial logic combined with memory, is the base of Finite-state machines, Turing machines as well as digital computers.

# Sequential Rook Attack

As an further example, a sequential logic may perform the same task as mentioned in Combinatorial Attack and Defend Map, but with less gates in up to seven cycles - similar to the bitboard techniques like Dumb7Fill:

+-------+ +------+ | | o--/64/-- empty(square) -/64/--| 64:1 |---->| |-----o result reliable / otherwise processing after reset +------+ | Comb. |-----o A8 is attacked by white rook from south ^ | Logic | +------+ | | o--/64/-- wrook(square) -/64/--| 64:1 |---->| |-->--+ +-----.+ | | | ^ o->| | | /6| | +-------+ | | | v +--------------+ | | | | | Latch |<----------+ reset o----| | +---^----------+ | clk

# See also

# Publications

- Alan H. Bond (
**1987**).*Broadcasting Arrays - A Highly Parallel Computer Architecture Suitable For Easy Fabrication*. pdf - Alan Clements (
**2005**).*Sequential Logic*. pdf

# External Links

- Finite-state machine from Wikipedia
- Harry Porter's Relay Computer
- Passport - Infinity Machine, YouTube Video

- 1976 lineup: Klaus Doldinger, Curt Cress, Wolfgang Schmid, Kristian Schultze