Real Number (E) - Mitsubishi Electric MELSEC-Q00U(J)CPU User Manual

5.3

Real Number (E)

The real number (E) is a device used to specify real numbers in sequence programs.
In sequence programs, specify it as E
(1) Specification range
(a) Real number setting range
• For single-precision floating-point data
128
-2 < Device
• For double-precision floating-point data
1024
-2 < Device
(b) When an overflow or underflow has occurred
The following table shows the operation of the CPU module when an overflow or underflow has occurred
during arithmetic operation.
OPERATION ERROR (error code: 4141)
(c) When a special value
If operation is performed with input data that contains a special value, "OPERATION ERROR" (error code:
4140) occurs.
*1 The special values are -0, unnormalized numbers, nonnumeric characters, and ±
(2) Specification method
Real numbers can be specified in sequence programs by the following expressions.
• Normal expression ••• A numeric value can be specified as it is.
10.2345 can be specified as E10.2345.
Ex.
• Exponential expression ••• A numeric value is specified by (Value) × 10
1234 is specified as E1.234 + 3.
Ex.
*1 + 3 represents 10
416
(example: E1.234). (
X1
EMOVP
-126 -126
-2 , 0, 2 Device < 2
-1022 -1022
-2 , 0, 2 Device < 2
Overflow
*1
is input
*1
3
in E1.234 + 3.
Page 497, Appendix 4.4)
E1.234 D0
128
1024
Underflow
Turned to 0 without any error
n
.
.