Chapter One data storage 1.1 bit and bit storage

1.1.1 Boolean operations

The data in the computer is represented by 0,1, which is called a bit.

A bit represents a symbol, not a numeric value. Because in addition to numbers, characters, sounds, images, and so on are all represented in bits. Bits represent what, to combine the context of the data

The operations that deal with the true and false values are called Boolean operations, and Boolean operations have three basic operations: with and, or, or XOR. They are the same as the subtraction operations, which belong to the two mesh operation. Each side of the operator has an input value of type Boolean, and a Boolean value is finally output.

The not operation is also a Boolean operation, which is a monocular operation. Only one Boolean input, the final output of a Boolean result value opposite to the input

1.1.2 Doors and Triggers

　　The gate is a kind of equipment, realizes the function of Boolean operation, it is the basic component of composing computer. The realization of the door can be realized by gear, relay, optical equipment and so on. The modern computer is realized by micro-circuit, and the bit voltage level is indicated. We do not need to focus on the implementation of the door, knowing that the sign of the door is sufficient:

A trigger is a circuit that can produce a 0 or 1 output, and its value remains constant unless the other circuit comes up with a temporary pulse that changes another value. In other words, the output value is converted between two values in an external stimulus.

Describes the cause of the trigger:

1. Show how the equipment is made by the door, this is the design process of digital circuit.

2. The concept of a trigger provides abstraction. When designing the logic of a digital circuit, it is possible to use a trigger to represent logic without worrying about which circuit to use specifically. The lower level abstraction is provided for the upper design of each layer in the circuit design.

3. Triggers are a way of storing bits in a modern computer. The trigger is set to the output value of 0 or 1, which can be sent to the input by some other circuit to adjust the output value, and some circuits use the output value of the trigger as its input value. As a result, many triggers are built into very small electronic circuitry to store data.

1.1.36 Binary Counting method

　　

Chapter One data storage 1.1 bit and bit storage