The arithmetic unit is composed of arithmetic components - Arithmetic Logical Unit (ALU), accumulators and registers. The role of the ALU is to perform arithmetic or logical operations on the incoming data, and the input source is two 8-bit data, which come from the accumulator and the data register. The ALU can complete the operations of adding, subtracting, and, or, comparing the size of these two data, and finally stores the result in the accumulator.
The operator has two functions:
(1) Perform various arithmetic operations.
(2) Perform various logical operations and perform logical tests, such as zero-value tests or comparisons of two values.
All operations performed by the arithmetic unit are commanded by control signals sent by the controller, and an arithmetic operation produces an operation result, and a logical operation produces a decision.
