AH Motion Controller – Operation Manual 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). 5.2.17. Floating-point Numbers (F, DF) The floating-point numbers are represented by decimal points in ISPSoft. For example, the floating-point number of 500 is 500.0. 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. b 31 b 0 Sign bit 0: Positive 1: Negative Equation:
( ) 127 ; .1 2 1 = Ч Ч − − B M B E S The single-precision floating-point numbers range from ±2 -126 to ±2 +128 , and correspond to the range from ±1.1755Ч10 -38 to ±3.4028Ч10 +38 . The AH500 series PLC uses two consecutive registers to form a 32-bit floating-point number. Take (D1, D0) for example. _5 D1(b15~b0) D0(b15~b0) 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 b0 b1 b2 b3 b4 b5 b6 b20 b21 b22 b23 b24 b28 b29 b30 b31 Exponent ( 8 bits) Mantissa (23bits) The position w here the d eci mal point is hid den Mantissa sign bit (0: Positive; 1: Negative) W hen b0~b31 are zeros, the content is zero. Double-precision Floating-point Numbers The floating-point number is represented by the 64-bit register.
The representation adopts the IEEE754 standard, and the format is as follows. 11-bit 52-bit b 63 b 0 Sign bit 0: Positive 1: Negative 5-12 8-bit 23-bit S Exponent Mantissa S E7 E6 E5 E1 E0 A22 A21 A20 A6 A5 A4 A3 A2 A1 A0 E S Exponent Mantissa