ALU

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Related to Arithmetic logic unit: Memory Unit

ALU

(computer science)

ALU

(processor)

ALU

(body)

ALU

(Arithmetic Logic Unit) The high-speed CPU circuit that does calculating and comparing. Numbers are transferred from memory into the ALU for calculation, and the results are sent back into memory. Alphanumeric data are sent from memory into the ALU for comparing. The results are tested by GOTOs; for example, IF ITEMA EQUALS ITEMB GOTO UPDATE ROUTINE.

Some chips have multiple ALUs that allow for simultaneous calculations. For example, Chromatic Research's Mpact media processor chip had 450 of them. It allowed audio, video and other multimedia processes to be performed simultaneously. See control unit and Mpact chip.


An ALU in 1957
This was an arithmetic logic unit you sit back and admire. It was part of Honeywell's Datamatic 1000 computer. (Image courtesy of Honeywell, Inc.)







Thirty Years Later
The ALU embedded within this 386 chip would fit on the end of a pencil eraser with room to spare. (Image courtesy of Intel Corporation.)
References in periodicals archive ?
The SC140 uses parallelism, with four multiply-accumulate units, four arithmetic logic units, four bit field units, two arithmetic address units and a five-stage pipeline.
The device features a MIPS32[R] 4KEc([R]) CPU core for system tasks, a DSP coprocessor subsystem that contains a second MIPS32 4KEc CPU core and a high-performance data-parallel unit (DPU) with eight lanes that have five 32-bit arithmetic logic units (ALUs) each.
The coprocessor adds three arithmetic logic units (ALUs) operating in parallel, improving performance by enabling one arithmetic operation and two address calculations on every clock cycle.
instruction-level parallelism (ILP) via very long instruction word (VLIW) driving multiple arithmetic logic units (ALUs) per lane
Silicon Objects are 16-bit medium grained devices like Arithmetic Logic Units, Multiply-Accumulators, Pattern-matching CAMs, Register Files, CRCs and Truth Functions.
Aimed at voice-over-IP and wireless base station applications, the 200 MHz LSI402ZX is a quad-issue machine with dual multiply-accumulate units and dual arithmetic logic units (ALUs) and includes two time division multiplexed (TDM) serial ports that support H.
The 40 Gbps capable iAC is a unique marriage of memory and networking technology, combining high-density 24MB special-purpose memory arrays -- an industry first -- with on-chip arithmetic logic units (ALUs) and policing circuitry.