W_INT_REAL: Type conversion (WORD -> INT -> REAL) (W_INT_REAL: Type conversion (WORD -> INT -> REAL))

Function description

This converts an input value with data type to data type and then data type .

As opposed to the WORD_TO_REAL conversion module (standard library), the W_INT_REAL module performs a conversion to an INT value prior to output of the REAL value. The result is, for example, that the input value FFFF is output as output value -1.0. (Not as with the WORD_TO_REAL module, for which the output value 9.183409e-41 is set).

As additional parameters, and are projected.

Representation in FBD

Representation:

Representation in LD

Appearance:

Representation in IL

Appearance:

LD WordValue 
W_INT_REAL 
ST RealValue

Representation in ST

Appearance:

RealValue := W_INT_REAL (WordValue);

Parameter description

Description of input parameters:

Parameter	Data type	Description
INP	WORD	Input value

Description of output parameters:

Parameter	Data type	Description
OUTP	REAL	Output value

EF is the abbreviation of Elementary Function.

This is a block used in a program which performs a predefined logical function.

A function does not have any information on the internal state. Several calls to the same function using the same input parameters return the same output values. You find information on the graphic form of the function call in the "[functional block (instance)]". Unlike a call to a function block, function calls include only an output which is not named and whose name is identical to that of the function. In FBD, each call is indicated by a unique [number] via the graphic block. This number is managed automatically and cannot be modified.

You position and configure these functions in your program in order to execute your application.

You can also develop other functions using the SDKC development kit.

EN stands for ENable; it is an optional block input. When the EN input is enabled, an ENO output is set automatically.

If EN = 0, the block is not enabled; its internal program is not executed, and ENO is set to 0.

If EN = 1, the block's internal program is run and ENO is set to 1. If an error occurs, ENO is set to 0.

If the EN input is not connected, it is set automatically to 1.

ENO

ENO stands for Error NOtification; this is the output associated with the optional input EN.

If ENO is set to 0 (because EN = 0 or in case of an execution error):

the status of the function block outputs remains the same as it was during the previous scanning cycle that executed correctly;
the output(s) of the function, as well as the procedures, are set to "0".

WORD

The type WORD is encoded in a 16 bit format and is used to perform processing on series of bits.

This table shows the upper/lower limits of each of the bases that can be used:

Base	Lower limit	Upper limit
Hexadecimal	16#0	16#FFFF
Octal	8#0	8#177777
Binary	2#0	2#1111111111111111

Examples of representation

Data	Representation in one of the bases
0000000011010011	16#D3
1010101010101010	8#125252
0000000011010011	2#11010011

REAL

The REAL type is encoded in a 32 bit format.

The possible value ranges are shown in the figure below:

When a result is:

between -1,175494e-38 and 1,175494e-38, it is considered to be a DEN;
less than -3.402824e+38, the symbol -INF (for - infinity) is displayed;
greater than +3.402824e+38, the symbol INF (for + infinity) is displayed;
undefined (square root of a negative number), the symbolNAN is displayed.

NOTE: The IEC 559 standard defines two classes of NAN: the silent NAN (QNAN) and the signaling NAN (SNAN). A QNAN is a NAN with a most significant fraction bit while an SNAN is a NAN without a most significant fraction bit (bit number 22). QNANs can be propagated via most arithmetic operations without throwing an exception. As for SNANs, they generally indicate n invalid operation when they are used as operands in arithmetic operations (see %SW17 and %S18).

NOTE: When a DEN (non-standardized number) is used as an operand, the result is not significant.