PLC data storage type - Solutions - Huaqiang Electronic Network

Probe domestic switch needle KG-300K needle head diameter is 3.0mm normally open switch needle

SMD aluminum electrolytic capacitor

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Huaqiang Square crystal original spot stock

1. The length of the data is a binary number used in the computer. The most basic storage unit is a bit. The 8-bit binary number is composed of 1 byte (Byte), and the 0th bit is the lowest bit (LSB). ), the 7th bit is the highest bit (MSB), as shown in Figure 2-7. Two bytes (16 bits) make up one word (Word), and two words (32 bits) form one double word (Doubleword), as shown in Figure 2-7. The number of consecutive bits occupied by bits, bytes, words, and double words is called length.
The "bit" of the binary number has only two values ​​of 0 and 1. The switching quantity (or digital quantity) has only two different states, such as the opening and closing of the contact, the loss of power and the power of the coil. In the S7-200 ladder diagram, they can be described by “bits”. If the bit is 1, the corresponding coil is in the power-on state, and the contact is in the transition state (normally open contact closed, normally closed contact open) If the bit is 0, it means the corresponding coil, and the state of the contact is opposite to the former.
2. Data type and data range
The data type of the S7-200 series plc can be string, boolean (0 or 1), integer and real (floating point). Boolean data refers to byte-type unsigned integers; integer numbers include 16-bit signed integers (INT) and 32-bit signed integers (DINT). Real data is represented by a 32-bit single precision number. The data type, length, and data range are shown in Table 2-7.
Table 2-7 Data Type, Length, and Data Range

Constant
Constants are often used in many instructions of the S7-200. The data length of a constant can be byte, word, and double word. The CPU stores constants in binary form, and the writing constants can be in binary, decimal, hexadecimal, ASCII, or real numbers. The writing format is as follows:
Decimal constant: 1234; Hexadecimal constant: 16#3AC6; Binary constant: 2#1010000111100000 ASCII code: "Show"; Real number (floating point number): +1.175495E-38 (positive number), -1.775495E-38 (negative number )