String Operations for IEC

ASCII To INT

Operator – Perform conversion of ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. to a INT Integer - [Data Type INT] - A 16-bit signed value. Integers are used where the value of the data is expected to be in the range of -32,768 to +32,767. value.

Inputs

Outputs

Q : (TYPE : INT) - The ASCII value converted to Int value.

Remarks

The value at the SRC[] array is separate ASCII value. Ex: SRC[0]- has the first ASCII value, Q – ASCII converted to Int Value.

ST Language

Q := AsciiToInt (Src[]) ;

FBD Language

LD Language

IL Language

Not Available.

Return to the Top: String Operations for IEC

ASCII to DINT

Operator – Perform conversion of ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. to a DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647. value.

Inputs

Outputs

Q : (TYPE :DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647.) - The ASCII value converted to Dint value.

Remarks

The value at the SRC[] array is separate ASCII value. Ex: SRC[0]- has the first ASCII value, Q – ASCII converted to Dint value.

ST Language

Q := AsciiToDint (Src[]) ;

FBD Language

LD Language

IL Language

Not Available.

Return to the Top: String Operations for IEC

ASCII To REAL

Operator – Performs conversion of ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. to a REAL REAL: Single precision floating point value - Real constant expressions must be valid number, and must include a dot ("."). If the user needs to enter a real expression having an integer value, add ".0" at the end of the number. The user can use "F" or "E" separators for specifying the exponent in case of a scientist representation. REAL is the default precision for floating points: such expressions do not need any prefix. value.

Inputs

Outputs

Q : (TYPE : REAL REAL: Single precision floating point value - Real constant expressions must be valid number, and must include a dot ("."). If the user needs to enter a real expression having an integer value, add ".0" at the end of the number. The user can use "F" or "E" separators for specifying the exponent in case of a scientist representation. REAL is the default precision for floating points: such expressions do not need any prefix.) - The ASCII value converted to Real value.

Remarks

The value at the SRC[] array is separate ASCII value. Ex: SRC[0]- has the first ASCII value, Q – ASCII converted to Real Value.

ST Language

Q := AsciiToReal (Src[]) ;

FBD Language

LD Language

IL Language

Not Available.

Return to the Top: String Operations for IEC

INT to ASCII

Operator – Perform conversion of INT to ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. value.

Inputs

SRC: (TYPE : INT Integer - [Data Type INT] - A 16-bit signed value. Integers are used where the value of the data is expected to be in the range of -32,768 to +32,767.) - This is the Input in Int format for conversion in ASCII value.

DST[ ] : (TYPE : USINT Unsigned Short Integer - [Data Type USINT] - An 8-bit unsigned value. Unsigned Short Integers are used where the value of the data is expected to be in the range of 0 (zero) to 255.[]) - The converted Dint into ASCII is placed in this array of DST. Converted INT to ASCII is terminated with Null character, so DST [] variable must have array size of maximum number of digits + 1.

Ex: #MAXLEN+1 .

Ex: if maximum number of digits allowed for conversion is 2 then DST [] variable must have array size of 3.

#POINT : (TYPE : INT) - This specifies the place of the point from right of the maximum length allocated.

#MAXLEN: (TYPE : INT) - The maximum number of digits allowed for conversion.

#FILL0: (TYPE : BOOL Boolean- [Data Type BOOL] - A single bit, binary value, or register/variable. Boolean points have only two possible values, 'TRUE' or 'FALSE'.) - Fills the vacant place after conversion from Dint to ASCII with zeroes.

Outputs

Q : (TYPE : BOOL) - The output is TRUE if the Dint value is converted to ASCII successfully.

Remarks

The value at the SRC are separate ASCII value. Ex: DST[0] - has the first ASCII value & so on.

ST Language

Q := IntToAscii (Src, Dst [], #Point, #MaxLen, #Fill0);

FBD Language

LD Language

IL Language

Return to the Top: String Operations for IEC

DINT to ASCII

Operator – Perform conversion of DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647. to ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. value.

Inputs

SRC: (TYPE : DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647.) - This is the Input in Dint format for conversion in ASCII value.

Ex: #MAXLEN+1

Ex: If maximum number of digits allowed for conversion is 2 then DST [] variable must have array size of 3.

#POINT : (TYPE : INT Integer - [Data Type INT] - A 16-bit signed value. Integers are used where the value of the data is expected to be in the range of -32,768 to +32,767.) - This specifies the place of the point from right of the maximum length allocated.

#MAXLEN: (TYPE : INT) - The maximum number of digits allowed for conversion.

Outputs

Q : (TYPE : BOOL) - The output is TRUE if the Dint value is converted to ASCII successfully.

Remarks

The value at the SRC are separate ASCII values. x: DST[0] - has the first ASCII value & so on.

ST Language

Q := DintToAscii (Src, Dst[], #Point, #MaxLen, #Fill0);

FBD Language

LD Language

IL Language

Return to the Top: String Operations for IEC

Hex To ASCII

See also: Enhanced IEC 61131 Guide

Function - Converts integer to string using hexadecimal A base-16 numbering system which uses the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F for numeral. basis.

Inputs

IN : DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647. - Integer value.

Outputs

Q : STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length. - String representing the integer in hexadecimal format.

Truth Table (examples)

In	Q
0	'0'
18	'12'
160	'A0'

Remarks

ST Language

HextoASCIIOP := HEXTOASCII ( HextoASCIIIP );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

IL Language

Not available.

Return to the Top: String Operations for IEC

REAL to ASCII

Operator – Perform conversion of REAL REAL: Single precision floating point value - Real constant expressions must be valid number, and must include a dot ("."). If the user needs to enter a real expression having an integer value, add ".0" at the end of the number. The user can use "F" or "E" separators for specifying the exponent in case of a scientist representation. REAL is the default precision for floating points: such expressions do not need any prefix. to ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. value.

Inputs

SRC: (TYPE : REAL) - This is the Input in Real format for conversion in ASCII value.

Ex: #MAXLEN+1

Ex: If maximum number of digits allowed for conversion is 2 then DST [] variable must have array size of 3.

#MAXLEN: (TYPE : INT) - The maximum number of digits allowed for conversion.

Outputs

Q : (TYPE : BOOL) - The output is TRUE if the Dint value is converted to ASCII successfully.

Remarks

The value at the SRC are separate ASCII value. Ex: DST[0] - has the first ASCII value & so on.

ST Language

Q := RealToAscii (Src, Dst [], #Point, #MaxLen, #Fill0);

FBD Language

LD Language

IL Language

Return to the Top: String Operations for IEC

ASCII To Hex

See also: Enhanced IEC 61131 Guide

Function - Converts string to integer using hexadecimal A base-16 numbering system which uses the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F for numeral. basis.

Inputs

Sin: (Type: STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length.) - String representing an integer in hexadecimal format.

Outputs

Q: (Type: DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647.) - Integer represented by the string.

Truth table (examples)

IN	Q
"	0
'12'	18
'A0'	160

Remarks

The function is case insensitive. The result is 0 for an empty string. The conversion stops before the first invalid character. In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the input must be loaded in the current result before calling the function.

ST Language

AsciiToHexOP := ASCIITOHEX ( AsciiToHexIP );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

IL Language

Not Available

Return to the Top: String Operations for IEC

CHAR ASCII Code

See also: Enhanced IEC 61131 Guide

Function - Get the ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. code of a character within a string.

Inputs

S1: (Type: STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length.) - Input string

POS: (Type: DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647.) - Position of the character within the string. (The first valid position is 0).

Outputs

Q: (Type: DINT) - ASCII code of the selected character or 0 if position is invalid.

Remarks

In LD language, the input rung (EN) enables the operation, and the output rung keeps the same value as the input rung. In IL language, the first parameter (IN) must be loaded in the current result before calling the function. The other input is the operand of the function.

ST Language

CharcacterASCIIcodeQ := CHARASCIICODE ( CharcacterASCIIcodeIP, CharcacterASCIIcodePos );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO is equal to EN.

IL Language

Not available.

Return to the Top: String Operations for IEC

Array To String

See also: Enhanced IEC 61131 Guide

Function - Copy an array of SINT Short Integer [Data Type SINT] - An 8-bit signed value. Short Integers are used where the value of the data is expected to be in the range of -128 to +127. to a STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length..

Inputs

SRC []: (Type: SINT) - Source array of SINT small integers

@DST: (Type: STRING) - Destination STRING.

COUNT: (Type: DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647.) - Numbers of characters to be copied.

Outputs

Q: (Type: DINT) - Number of characters copied.

Remarks

In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. This function copies the COUNT first elements of the SRC array to the characters of the DST string. The function checks the maximum size of the destination string and adjust the COUNT number if necessary.

ST Language

ArrayToStringQ := ARRAYTOSTRING ( ArrayToStringS, ArrayToStringD, ArrayToStringCount );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

Return to the Top: String Operations for IEC

String To Array

See also: Enhanced IEC 61131 Guide

Function - Copies the characters of a STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length. to an array of SINT Short Integer [Data Type SINT] - An 8-bit signed value. Short Integers are used where the value of the data is expected to be in the range of -128 to +127..

Inputs

SRC : STRING - Source STRING.

DST : SINT - Destination array of SINT small integers.

Outputs

Q : DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647. - Number of characters copied.

Remarks

In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the input must be loaded in the current result before calling the function. This function copies the characters of the SRC string to the first characters of the DST array. The function checks the maximum size destination arrays and reduces the number of copied characters if necessary.

ST Language

StringToArrayQ := STRINGTOARRAY ( StringtoArrayIP, StringToArrayDest );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

Return to the Top: String Operations for IEC

String To UArray

This block is supported in enhanced IEC only.

See also: Enhanced IEC 61131 Guide

Function - Copies the characters of a STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length. to an array of USINT Short Integer [Data Type SINT] - An 8-bit signed value. Short Integers are used where the value of the data is expected to be in the range of -128 to +127..

Inputs

SRC : STRING - Source STRING.

DST : USINT - Destination array of USINT small integers.

Outputs

Remarks

ST Language

StringToArrayQ := STRINGTOUARRAY ( StringtoArrayIP, StringToArrayDest );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

Return to the Top: String Operations for IEC

UArray To String

This block is supported in enhanced IEC only.

See also: Enhanced IEC 61131 Guide

Function - Copy an array of USINT Short Integer [Data Type SINT] - An 8-bit signed value. Short Integers are used where the value of the data is expected to be in the range of -128 to +127. to a STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length..

Inputs

SRC [] : (TYPE: USINT Unsigned Short Integer - [Data Type USINT] - An 8-bit unsigned value. Unsigned Short Integers are used where the value of the data is expected to be in the range of 0 (zero) to 255.) - Source array of USINT Unsigned Short Integer - [Data Type USINT] - An 8-bit unsigned value. Unsigned Short Integers are used where the value of the data is expected to be in the range of 0 (zero) to 255. small integers.

@DST : (TYPE: STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length.) - Destination STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length..

COUNT : (TYPE: DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647.) - Numbers of characters to be copied.

Outputs

Remarks

In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the input must be loaded in the current result before calling the function. This function copies the COUNT first elements of the SRC array to the characters of the DST string. The function checks the maximum size destination string and adjust the COUNT number if necessary.

ST Language

Output := UARRAYTOSTRING ( Src1, STRINGTOCOPY, 20);

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

NOTE:

On Debug (Watch) Window

As long the data is ASCII, it is displayed correctly, but if there are any numeric values (not ASCII) it is represented as $ followed by the respective numeric value. For example - string has "ABC" followed by numeric 0123 (not ASCII) values, then it displays as ABC$00$01$02$03.

On Graphics

In graphics, we have an ASCII object, which will only display ASCII and not numeric values. For example –

If the data is "ABC" followed by 0123 numeric, it will display ABC only.

If the data is 0123 numeric followed by "ABC", no string will be displayed.

Return to the Top: String Operations for IEC

String Left

See also: Enhanced IEC 61131 Guide

Function - Extracts characters of a string on the left.

Inputs

IN : STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length. - Character string.

NBC : DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647. - Number of characters to extract.

Outputs

Q : STRING - String containing the first NBC characters of IN.

Remarks

In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the first input (the string) must be loaded in the current result before calling the function. The second argument is the operand of the function.

ST language

StringLeftOut := STRINGLEFT ( StringInput, StringLeftCount );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

IL Language

Not available.

Return to the Top: String Operations for IEC

String Mid

See also: Enhanced IEC 61131 Guide

Function - Extracts characters of a string at any position.

Inputs

POS : DINT - Position of the first character to extract (first character of IN is at position 0).

Outputs

Q : STRING - String containing the first NBC characters of IN.

Remarks

The first valid position is 0. In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the first input (the string) must be loaded in the current result before calling the function. Other argument are operands of the function, separated by commas.

ST Language

StringMidOut := STRINGMID ( StringInput, StringMidCount, StringMidPos )

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

IL Language

O1: LD IN

MID NBC, POS

ST Q

Return to the Top: String Operations for IEC

String Right

See also: Enhanced IEC 61131 Guide

Function - Extracts characters of a string on the right.

Inputs

IN : STRING - Character string.

NBC : DINT - Number of characters to extract.

Outputs

Q : STRING - String containing the last NBC characters of IN.

Remarks

ST Language

StringRIghtOut := STRINGRIGHT ( StringInput, StringRightCOunt );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

IL Language

Return to the Top: String Operations for IEC

String Find

See also: Enhanced IEC 61131 Guide

Function - Finds position of characters in a string.

Inputs

STR : STRING - String containing searched characters.

Outputs

POS : DINT - Position of the first character of STR in IN, or 0 if not found.

Remarks

The first valid character position is 1. A return value of 0 means that the STR string has not been found. Search is case sensitive. In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the first input (the string) must be loaded in the current result before calling the function. The second argument is the operand of the function.

ST Language

StringFindPos := STRINGFIND ( StringInput, StringFind1 );

FBD Language

LD Language

IL Language

Not available.

Return to the Top: String Operations for IEC

String Replace

See also: Enhanced IEC 61131 Guide

Function - Replaces characters in a string.

Inputs

STR : STRING - String containing the characters to be inserted in place of NDEL removed characters.

NDEL : DINT Double Integer - [Data Type DINT] - A 32-bit signed value. Double Integers are used where the value of the data is expected to be in the range of -2,147,483,648 to +2,147,483,647. - Number of characters to be deleted before insertion of STR.

POS : DINT - Position where characters are replaced (first character position is 0).

Outputs

Q : STRING Modified string.

Remarks

The first valid character position is 0. In LD language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung. In IL, the first input (the string) must be loaded in the current result before calling the function. Other arguments are operands of the function, separated by commas.

ST Language

StringReplaceOut := STRINGREPLACE ( StringInput, StringReplaceInsert, StringReplaceCount, StringReplacePos );

FBD Language

LD Language

The function is executed only if EN is TRUE.

ENO keeps the same value as EN.

IL Language

Return to the Top: String Operations for IEC

String Concatenate

See also: Enhanced IEC 61131 Guide

Function - Concatenate or link together in strings.

Inputs

S2: (Type: STRING) - Any string variable or constant expression.

Outputs

Sout: (Type: STRING) - Concatenation of all inputs.

Remarks

In FBD or LD language, the block may have up to 16 inputs. In IL or ST, the function accepts a variable number of inputs (at least 2). NOTE: The user can also use the "+" operator to concatenate strings.

ST Language

StringConacatOP := STRINGCONCAT ( StringConcatIp1, StringConactIp2 );

FBD Language

LD Language

IL Language

Not available.

Return to the Top: String Operations for IEC

Variable String Length

Operator – Length of a given input string.

Inputs

S[ ] : (TYPE : USINT Unsigned Short Integer - [Data Type USINT] - An 8-bit unsigned value. Unsigned Short Integers are used where the value of the data is expected to be in the range of 0 (zero) to 255.[]) - S is the source string ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. value.

Outputs

LEN : (TYPE :INT Integer - [Data Type INT] - A 16-bit signed value. Integers are used where the value of the data is expected to be in the range of -32,768 to +32,767.) - Length of the elements in array S.

Remarks

En is the Enable input & Eno is the enable output. En & Eno will be in same state.

ST Language

LEN := StringLen (S[]);

FBD Language

LD Language

IL Language

Not Available.

Return to the Top: String Operations for IEC

Constant String Length

Operator – Length of a given input string.

Inputs

S : (TYPE : STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length.) - S is the string in ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. value.

Outputs

ST Language

LEN:= StringLen ( 'Test' );

FBD Language

LD Language

IL Language

Return to the Top: String Operations for IEC

Compare Strings

Operator – Perform comparison of String variables.

Inputs

S1[ ] : (TYPE : USINT Unsigned Short Integer - [Data Type USINT] - An 8-bit unsigned value. Unsigned Short Integers are used where the value of the data is expected to be in the range of 0 (zero) to 255.[]) - S1 is the array of ASCII values placed to compare with the input at S2.

S2[ ] : (TYPE : USINT[]) - S2 is the array of ASCII values to which input S1 is compared with.

#COUNT : (TYPE : INT Integer - [Data Type INT] - A 16-bit signed value. Integers are used where the value of the data is expected to be in the range of -32,768 to +32,767.) - The number of characters to be compared.

Outputs

Q : (TYPE :BOOL) - Output goes high if the input ASCII values are equal for a given count.

Remarks

Each element of array S1[] is compared with each element of array S2[]. Ex: S1[0] is compared with value at S2[0], till the given count at #COUNT input.

ST Language

Q := CmpStringVar (S1[], S2[], #Count) ;

FBD Language

LD Language

IL Language

Not Available.

Return to the Top: String Operations for IEC

Compare String with Constant Data

Operator – Perform comparison of String with a constant.

Inputs

S1[ ] : (TYPE : USIN Unsigned Short Integer - [Data Type USINT] - An 8-bit unsigned value. Unsigned Short Integers are used where the value of the data is expected to be in the range of 0 (zero) to 255.T[]) - S1 is the array of ASCII values placed to compare with the input at S2.

S2: (TYPE : STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length.) - S2 is the string to which input S1 is compared.

Outputs

Q : (TYPE : BOOL Boolean- [Data Type BOOL] - A single bit, binary value, or register/variable. Boolean points have only two possible values, 'TRUE' or 'FALSE'.) - Output goes high if the inputs are equal.

Remarks

The value at the S1[] array is character wise ASCII value. Ex: S1[0]- has the first alphabet’s ASCII value, S1[1]- has the second alphabet’s ASCII value & so on.

ST Language

Q: = CmpStringConst (S1[] , S2) ;

FBD Language

LD Language

IL Language

Not Available.

Return to the Top: String Operations for IEC

Set String

Operator – Sets the ASCII ASCII - American Standard Code for Information Interchange - ASCII-coded characters are single-byte values in the range of 0 (zero) to 127. Codes in the range 128 to 255 are not defined by the ASCII standard, but rather by the equipment manufacturer. value of the source at the destination array.

Inputs

SRC : (TYPE : STRING String - [Data Type STRING] - A variable-length succession of characters. Each character is represented by one byte. a. Cscape strings are delimited by the Single Quote character ('). b. Cscape strings may be zero characters in length.) - SRC is the source string.

Outputs

Q : (TYPE :BOOL Boolean- [Data Type BOOL] - A single bit, binary value, or register/variable. Boolean points have only two possible values, 'TRUE' or 'FALSE'.) - Output goes high if the SetString is successful.

Remarks

The value at the DST[] array is character wise ASCII value. Ex: DST[0]- has the first alphabet’s ASCII value, DST[1]- has the second alphabet’s ASCII value & so on.

ST Language

Q := SetString(Src, Dst[]);

FBD Language

LD Language

IL Language

Return to the Top: String Operations for IEC

Calculate CRC16

See also: Enhanced IEC 61131 Guide

Function - Calculates a CRC16 on the characters of a string.

Inputs

Outputs

Q : DINT CRC16 calculated on all the characters of the string.

Remarks

In LD language, the input rung (EN) enables the operation, and the output rung keeps the same value as the input rung. In IL language, the input parameter (IN) must be loaded in the current result before calling the function. The function calculates a MODBUS CRC16, initialized at 16#FFFF value.