Chapter 2 Devices The PLC uses four types of values to execute the operation according to different control purposes. The functions of these values are illustrated as follows: 1. Binary number (BIN) The PLC adopts the binary system to operate the values. 2. Decimal number (DEC) The decimal number in the PLC is used as the setting value of the timer (T) or the setting value of the counter (C/HC). For example, TMR C0 50 (constant K). the device number. For example, M10 and T30 (device number) as the number before or after the decimal point. For example, X0.0, Y0.11, and D10.0 (device number). the constant K: It is used as the operand in the applied instruction.
For example, MOV 123 D0 (constant K). 3. Binary-coded decimal (BCD) A decimal value is represented by a nibble or four bits, and therefore sixteen consecutive bits can represent a four-digit decimal value. 4. Hexadecimal number (HEX) The hexadecimal number in the PLC is used as the constant 16#: It is used as the operand in the applied instruction. For example, MOV 16#1A2B D0 (hexadecimal constant). The following is the reference table: 2.2.2 Floating-point Numbers The floating-point numbers are represented by decimal points in ISPSoft. For example, the floating-point number of 500 is 500.0.
2.2.2.1 Single-precision Floating-point Numbers The floating-point number is represented by the 32-bit register. The representation adopts the IEEE754 standard, and the format is as follows.
2-7 Binary number Decimal number Binary-coded decimal number Hexadecimal number (BIN) (DEC) (BCD) (HEX) Internal operation in the PLC Decimal constant, device number Instruction related to the binary-code decimal number Hexadecimal constant, device number 0000 0 0000 0 0001 1 0001 1 0010 2 0010 2 0011 3 0011 3 0100 4 0100 4 0101 5 0101 5 0110 6 0110 6 0111 7 0111 7 1000 8 1000 8 1001 9 1001 9 1010 10 - A 1011 11 - B 1100 12 - C 1101 13 - D 1110 14 - E 1111 15 - F 10000 16 0001 0000 10 10001 17 0001 0001 11