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What is the difference between arithmetic and logic unit (ALU) ? |
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Answer» ARITHMETIC AND LOGIC UNIT (ALU) • An ALU is a combinational circuit that performs arithmetic and logical operation on the data stored in accumulator. • Results of operation by ALU are placed back in the accumulator. • Typical operations performed by ALU includes add, shift/rotate, compare, increment, decrement, AND, OR, XOR, complement, clear, pre-set etc. • Apart from performing these operation, ALU also contains important information about certain conditions that occur during these mathematical operation. • These conditions i.e. occurrence of carry, borrow, zero, negative or even parity results are stored in register called flag register and the individual bits are called flag bits. • The number of bits is the most important factor determining the capabilities of the processor. Hence the size of ALU defines the size of the microprocessor. |
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