accumulator

accumulator

A hardware register used to hold the results or partial results of arithmetic and logical operations.

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accumulator

1. a rechargeable device for storing electrical energy in the form of chemical energy, consisting of one or more separate secondary cells

2. Horse racing Brit a collective bet, esp on four or more races, in which the stake and winnings on each successive race are carried forward to become the stake on the next, so that both stakes and winnings accumulate progressively so long as the bet continues to be a winning one

3. 

a. a register in a computer or calculator used for holding the results of a computation or data transfer

b. a location in a computer store in which arithmetical results are produced

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accumulator [ə′kyü·myə‚lād·ər]

(aerospace engineering)

A device sometimes incorporated in the fuel system of a gas-turbine engine to store fuel and release it under pressure as an aid in starting.

(chemical engineering)

An auxiliary ram extruder on blow-molding equipment used to store melted material between deliveries.

(computer science)

A specific register, in the arithmetic unit of a computer, in which the result of an arithmetic or logical operation is formed; here numbers are added or subtracted, and certain operations such as sensing, shifting, and complementing are performed. Also known as accumulator register; counter.

(electricity)

storage battery

(engineering)

air vessel

(mechanical engineering)

A device, such as a bag containing pressurized gas, which acts upon hydraulic fluid in a vessel, discharging it rapidly to give high hydraulic power, after which the fluid is returned to the vessel with the use of low hydraulic power.

A device connected to a steam boiler to enable a uniform boiler output to meet an irregular steam demand.

A chamber for storing low-side liquid refrigerant in a refrigeration system. Also known as surge drum; surge header.

(petroleum engineering)

A tank or chamber for receiving and temporarily storing a liquid used in a gas processing plant during a continuous process.

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(processor)

accumulator - In a central processing unit, a register in which intermediate results are stored. Without an accumulator, it would be necessary to write the result of each calculation (addition, multiplication, shift, etc.) to main memory and read them back. Access to main memory is slower than access to the accumulator which usually has direct paths to and from the arithmetic and logic unit (ALU). The canonical example is summing a list of numbers. The accumulator is set to zero initially, each number in turn is added to the value in the accumulator and only when all numbers have been added is the result written to main memory. Modern CPUs usually have many registers, all or many of which can be used as accumulators. For this reason, the term "accumulator" is somewhat archaic. Use of it as a synonym for "register" is a fairly reliable indication that the user has been around for quite a while and/or that the architecture under discussion is quite old. The term in full is almost never used of microprocessor registers, for example, though symbolic names for arithmetic registers beginning in "A" derive from historical use of the term "accumulator" (and not, actually, from "arithmetic"). Confusingly, though, an "A" register name prefix may also stand for "address", as for example on the Motorola 680x0 family. 2. A register, memory location or variable being used for arithmetic or logic (as opposed to addressing or a loop index), especially one being used to accumulate a sum or count of many items. This use is in context of a particular routine or stretch of code. "The FOOBAZ routine uses A3 as an accumulator."