Control unit

hardwiredhardwired controlHardwired control unitcontrol modulecontrol unit (CU)hard wiredhard-wiredhardwired programhardwiringlogic
The control unit (CU) is a component of a computer's central processing unit (CPU) that directs the operation of the processor.wikipedia
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Central processing unit

CPUprocessorprocessors
The control unit (CU) is a component of a computer's central processing unit (CPU) that directs the operation of the processor.
Traditionally, the term "CPU" refers to a processor, more specifically to its processing unit and control unit (CU), distinguishing these core elements of a computer from external components such as main memory and I/O circuitry.

Von Neumann architecture

von Neumannvon Neumann bottleneckvon Neumann machine
John von Neumann included the control unit as part of the von Neumann architecture.

Instruction unit

Instruction Fetch Unit
On some processors, the Control Unit may be further broken down into additional units, such as an instruction unit or scheduling unit to handle scheduling, or a retirement unit to deal with results coming from the instruction pipeline.
It is a part of the control unit, which in turn is part of the CPU.

Instruction set architecture

instruction setinstructionsinstruction
The CU is normally the first CPU unit to accept from an externally stored computer program a single instruction (based on the CPU's instruction set).
There are two basic ways to build a control unit to implement this description (although many designs use middle ways or compromises):

John von Neumann

von NeumannJ. von NeumannNeumann, John von
John von Neumann included the control unit as part of the von Neumann architecture.

Register-transfer level

RTLregister transfer levelhigh-level languages
The CU receives external instructions or commands which it converts into a sequence of control signals that the CU applies to the data path to implement a sequence of register-transfer level operations.

Plugboard

control panelplug boardcontrol panel wiring
This results in a computer that could run a complete program and require no human intervention to make hardware changes between instructions (as had to be done when using only punch cards for computations before stored programmed computers with CUs were invented).

Instruction pipelining

instruction pipelinepipelinepipelined
On some processors, the Control Unit may be further broken down into additional units, such as an instruction unit or scheduling unit to handle scheduling, or a retirement unit to deal with results coming from the instruction pipeline.

Combinational logic

combinationalcombinatorial logiccombinational circuit
Hardwired control units are implemented through use of combinational logic units, featuring a finite number of gates that can generate specific results based on the instructions that were used to invoke those responses.

Reduced instruction set computer

RISCreduced instruction set computingreduced instruction set
This architecture is preferred in reduced instruction set computers (RISC) as they use a simpler instruction set.

Flowchart

flow chartflowchartsflow charts
The algorithm for the microprogram control unit, unlike the hardwired control unit, is usually specified by flowchart description.

DIGIC

DIGIC 4DIGIC 6CHDK
Digital Imaging Integrated Circuit (often styled as "DiG!C") is Canon Inc.'s name for a family of signal processing and control units for digital cameras and camcorders.

Microcode

microprogrammicroprogrammingmicroprogrammed
Microcode is used in general-purpose central processing units, although in current desktop CPUs it is only a fallback path for cases that the faster hardwired control unit cannot handle.

Control store

Writeable Control Storecontrol storagewritable control store
A control store is the part of a CPU's control unit that stores the CPU's microprogram.

Computer data storage

main memorystoragememory
This distinction was extended in the Von Neumann architecture, where the CPU consists of two main parts: The control unit and the arithmetic logic unit (ALU).

AMD Am2900

Am2901AMD 29012901
They were constructed with bipolar devices, in a bit-slice topology, and were designed to be used as modular components each representing a different aspect of a computer control unit (CCU).

MikroSim

Since MikroSim operability starts on the basis of microcode development, defined as a sequence of micro instructions (microcoding) for a virtual control unit, the software's intention is on first approach a microcode simulator with various levels of abstractions including the ability of CPU simulators and instruction set emulators.

Dedicated console

dedicateddedicated consolesdedicated video game console
Unlike almost all later consoles, these systems were typically not computers (in which a CPU is running a piece of software), but contained a hardwired game logic.

Computer hardware

hardwarepersonal computer hardwaredevice
This describes a design architecture for an electronic digital computer with subdivisions of a processing unit consisting of an arithmetic logic unit and processor registers, a control unit containing an instruction register and program counter, a memory to store both data and instructions, external mass storage, and input and output mechanisms.

MIC-1

It consists of a very simple control unit that runs microcode from a 512-words store.