Z_u Arithmetic logical unit

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ALU\LB The symbol ALU. ABiIyhjRZB Type A and B (operand) R in the operation results. FADoXe[^XB F is controlled from the center of the input, D status of the output.

Z_u ijA ALU ( A rithmetic L ogic U nit)A Rs[^}CNvZbT ( CPU )\i1B Arithmetic logic unit (ZANRONRISOUCHI salt), ALU (A rithmetic L ogic U nit), also known as the computer is equipped with a microprocessor (CPU) one of the parts.

ALUCPUjsjbgB ALU the CPU is the heart of the execution units are part of. ALUlXlZ_ZB ALU a variety of simple arithmetic and logical operations and processes.

Rs[^ALU2\g(Rs[^1g-`g)B ALU's current computer is a complement to use the expression (on the computer early one's complement, or use the code - mantissa form or use).

[ W ] tHEmC} von Neumann's proposal

1945N AwWEtHEmC}EDVACVRs[^bI|[gALUTOB In 1945, mathematician John von Neumann, EDVAC new computer, called the report of ALU basic concept was proposed. 1946N AWvXg (IAS)Rs[^v]AIAS}VRs[^^B In 1946, he proposed to further develop the Institute for Advanced Study (IAS) engaged in the design of the computer in the IAS machine prototype of the many computer. AALUKvMTB In the proposal, ALU and what he believed should be outlined. tHEmC}ARs[^lZ{IwvZ`Ap(ALU)K{qB Von Neumann, a computer containing the simple arithmetic calculation of basic math and to define its own for the organ (ALU) is required.

[ W ] ALU ALU operation

ALUB Many ALU behavior, such as the following.

• Z ( Z A Z A Z ) Integer arithmetic operations (addition, subtraction, multiplication)
• _Z ( AND A NOT A OR A XOR ) Logic (AND, NOT, OR, XOR)
• rbgVtg ([hwrbgE()Vtg([e[g)B g) Bit-shift operation (the specified number of bits-word sentence to the right (or left) shift (or rotates). Coded extension may)

T^IALUZ_sB In a typical ALU Integer division and floating point numbers do not handle. Zs@B These operations as a way to process something like the following.

• \tgEFAG~[V (AZuR[hCu) () Software emulation (in general assembler code libraries are implemented) (the slowest)
• }CNR[hALUG~[V(x) Micro-code emulation ALU operation does not exist (medium speed)
• Z_jbg( FPU )n[hEFAiB Dividers or floating point unit (FPU) as implemented in other parts of the hardware. RvZbT`() Sometimes the coprocessor takes the form of (the fastest)

[ W ] o input and output

ALUf[^( Iyh)A uR[hs(Z)FB ALU should be treated as the input data (operands and the call) to receive and control system should be run on the code from processing (arithmetic) to the type of recognition. oZB The output is the result of the operation.

ALUfUCAXe[^XWX^tOAtZXe[^XWX^tOXB Many in the design of the ALU, as input status register and take the flag on the condition of workers, and other operations as a result of changes the status registers and flags of the condition. A L[AL[oA ZpI[o[t[Xe[^XWX^\A [ZXe[^XWX^\sB For example, Carrie, and as an input, output and carry, or arithmetic overflow, or displayed in the status register, zero division or displayed in the status register and do.

[ W ] A See also

• CPU CPU
• Z Adder
• Z Multiplier

u Z_u vRs[^AB The "arithmetic logic unit," a computer-related items unfinished. LMli Portal:Rs[^ j B This article expanded and people are looking forSARU (Portal: Computer).