Read variable using symbols

Collaboration diagram for Read variable using symbols:

Functions
MLPIRESULT	mlpiLogicReadVariableBySymbolBool8 (const MLPIHANDLE connection, const WCHAR16 *symbol, BOOL8 *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolChar (const MLPIHANDLE connection, const WCHAR16 *symbol, CHAR *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolUchar (const MLPIHANDLE connection, const WCHAR16 *symbol, UCHAR *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolShort (const MLPIHANDLE connection, const WCHAR16 *symbol, SHORT *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolUshort (const MLPIHANDLE connection, const WCHAR16 *symbol, USHORT *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolLong (const MLPIHANDLE connection, const WCHAR16 *symbol, LONG *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolUlong (const MLPIHANDLE connection, const WCHAR16 *symbol, ULONG *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolLlong (const MLPIHANDLE connection, const WCHAR16 *symbol, LLONG *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolUllong (const MLPIHANDLE connection, const WCHAR16 *symbol, ULLONG *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolFloat (const MLPIHANDLE connection, const WCHAR16 *symbol, FLOAT *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolDouble (const MLPIHANDLE connection, const WCHAR16 *symbol, DOUBLE *data)
MLPIRESULT	mlpiLogicReadVariableBySymbolString (const MLPIHANDLE connection, const WCHAR16 *symbol, WCHAR16 *data, const ULONG numElements)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayBool8 (const MLPIHANDLE connection, const WCHAR16 *symbol, BOOL8 *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayChar (const MLPIHANDLE connection, const WCHAR16 *symbol, CHAR *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayUchar (const MLPIHANDLE connection, const WCHAR16 *symbol, UCHAR *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayShort (const MLPIHANDLE connection, const WCHAR16 *symbol, SHORT *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayUshort (const MLPIHANDLE connection, const WCHAR16 *symbol, USHORT *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayLong (const MLPIHANDLE connection, const WCHAR16 *symbol, LONG *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayUlong (const MLPIHANDLE connection, const WCHAR16 *symbol, ULONG *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayLlong (const MLPIHANDLE connection, const WCHAR16 *symbol, LLONG *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayUllong (const MLPIHANDLE connection, const WCHAR16 *symbol, ULLONG *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayFloat (const MLPIHANDLE connection, const WCHAR16 *symbol, FLOAT *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayDouble (const MLPIHANDLE connection, const WCHAR16 *symbol, DOUBLE *data, const ULONG numElements, ULONG *numElementsRet)
MLPIRESULT	mlpiLogicReadVariableBySymbolArrayVoid (const MLPIHANDLE connection, const WCHAR16 *symbol, void *data, const ULONG dataSize, ULONG *dataSizeRet)

Detailed Description

The following functions provide symbolic read access to logic variables.

Attention

The addresses of the variables of the symbolic access might change on every download, reset origin or online change of the PLC application, so you have to stop each variable access before you load or change the PLC application!

The table shows the PLC data types within the IEC61131 environment 'IndraLogic' and the corresponding data types within the C/C++ environment (e.g. 'Workbench OEM') of the MLPI. On reading variables by symbols, on default, you use the functions below named after the MLPI data type like mlpiLogicReadVariableBySymbolUlong. If you include the header mlpiLogicHelper.h, you can also use the equivalent functions named after the IEC61131 data types like mlpiLogicReadVariableBySymbolDword or like mlpiLogicReadVariableBySymbolUdint.

Number of Bits	Data types of PLC	Data types of MLPI
8	BOOL	BOOL8
8	SINT	CHAR
16	INT	SHORT
32	DINT	LONG
64	LINT	LLONG
8	USINT	UCHAR
16	UINT	USHORT
32	UDINT	ULONG
64	ULINT	ULLONG
8	BYTE	UCHAR
16	WORD	USHORT
32	DWORD	ULONG
64	LWORD	ULLONG
32	REAL	FLOAT
64	LREAL	DOUBLE
8n	STRING	WCHAR16
16n	WSTRING	WCHAR16

Function Documentation

MLPIRESULT mlpiLogicReadVariableBySymbolBool8	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		BOOL8 *	data
	)

This function reads a boolean value (BOOL, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
BOOL8 data = FALSE;
MLPIRESULT result = mlpiLogicReadVariableBySymbolBool8(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolChar	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		CHAR *	data
	)

This function reads an 8 bit signed value (SINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
CHAR data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolChar(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolUchar	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		UCHAR *	data
	)

This function reads an 8-bit unsigned value (BYTE, USINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
UCHAR data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolUchar(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolShort	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		SHORT *	data
	)

This function reads a 16-bit signed value (INT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
SHORT data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolShort(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolUshort	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		USHORT *	data
	)

This function reads a 16-bit unsigned value (WORD, UINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
USHORT data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolUshort(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolLong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		LONG *	data
	)

This function reads a 32-bit signed value (DINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
LONG data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolLong(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolUlong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		ULONG *	data
	)

This function reads a 32-bit unsigned value (DWORD, UDINT, TIME, DATE, DATE_AND_TIME, ..., MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
ULONG data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolUlong(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolLlong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		LLONG *	data
	)

This function reads a 64-bit signed value (LINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
LLONG data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolLlong(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolUllong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		ULLONG *	data
	)

This function reads a 64-bit unsigned value (LWORD, ULINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
ULLONG data = 0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolUllong(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolFloat	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		FLOAT *	data
	)

This function reads a 32-bit floating point value (single precision, REAL, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
FLOAT data = 0.0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolFloat(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolDouble	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		DOUBLE *	data
	)

This function reads a 64-bit floating point value (double precision, LREAL, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value will be stored.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
DOUBLE data = 0.0;
MLPIRESULT result = mlpiLogicReadVariableBySymbolDouble(connection, L"Application.PlcProg.x1", &data);

MLPIRESULT mlpiLogicReadVariableBySymbolString	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		WCHAR16 *	data,
		const ULONG	numElements
	)

This function reads a character string value (STRING, MlpiLogicType) from a variable by symbolic access. You can use this function not only for string variables, but also for other simple types and arrays of simple types. In this case, the function returns a string representation of the given value. The values of a string represented array will be separated by spaces. The reading of values as a string can be useful if you only want to display the variable as a string and you don't need to know the type of the variable.

Hint:

From version 1.4.0.0 of the MLPI server this function supports arrays of simple types and furthermore different display types to show the string represented values in hexadecimal, decimal, binary or boolean format. To use the display extension you have to add a prefix to your symbol. The prefixes are defined in the helper header "mlpiLogicHelper.h". Hint: From Version 1.11.8.0 of the MLPI server this function supports data types TIME, DATE, DATE_AND_TIME, and TIME_OF_DAY

Data types of PLC	Valid prefixes for argument 'symbol'	Example of argument 'symbol'	Example of result 'data'
BOOL	none	L"Application.PlcProg.locVarBool"	L"TRUE"
	MLPI_READ_VAR_DISPLAY_TYPE_BOOLEAN	L"BLN:Application.PlcProg.locVarBool"	L"TRUE"
	MLPI_READ_VAR_DISPLAY_TYPE_DEC	L"DEC:Application.PlcProg.locVarBool"	L"1"
	MLPI_READ_VAR_DISPLAY_TYPE_HEX	L"HEX:Application.PlcProg.locVarBool"	L"0x01"
	MLPI_READ_VAR_DISPLAY_TYPE_BIN	L"BIN:Application.PlcProg.locVarBool"	L"0b0000.0001"
BYTE, WORD, DWORD, LWORD	none	L"Application.PlcProg.locVarByte"	L"222"
	MLPI_READ_VAR_DISPLAY_TYPE_DEC	L"DEC:Application.PlcProg.locVarByte"	L"222"
	MLPI_READ_VAR_DISPLAY_TYPE_HEX	L"HEX:Application.PlcProg.locVarByte"	L"0xDE"
	MLPI_READ_VAR_DISPLAY_TYPE_BIN	L"BIN:Application.PlcProg.locVarByte"	L"0b1101.1110"
USINT, UINT, UDINT, ULINT	none	L"Application.PlcProg.locVarUint"	L"42"
	MLPI_READ_VAR_DISPLAY_TYPE_DEC	L"DEC:Application.PlcProg.locVarUint"	L"42"
	MLPI_READ_VAR_DISPLAY_TYPE_HEX	L"HEX:Application.PlcProg.locVarUint"	L"0x2A"
	MLPI_READ_VAR_DISPLAY_TYPE_BIN	L"BIN:Application.PlcProg.locVarUint"	L"0b0010.1010"
SINT, INT, DINT, LINT	none	L"Application.PlcProg.locVarInt"	L"-16982"
	MLPI_READ_VAR_DISPLAY_TYPE_DEC	L"DEC:Application.PlcProg.locVarInt"	L"-16982"
	MLPI_READ_VAR_DISPLAY_TYPE_HEX	L"HEX:Application.PlcProg.locVarInt"	L"0xBDAA"
	MLPI_READ_VAR_DISPLAY_TYPE_BIN	L"BIN:Application.PlcProg.locVarInt"	L"0b1011.1101.1010.1010"
REAL, LREAL	none	L"Application.PlcProg.locVarReal"	L"3.141592"
STRING, WSTRING	none	L"Application.PlcProg.locVarString"	L"Don't panic!"
TIME	none	L"Application.PlcProg.locVarTime "	L"5d12h34m15s12ms"
DATE	none	L"Application.PlcProg.locVarTime "	L"2010-03-29"
DATE_AND_TIME	none	L"Application.PlcProg.locVarTime "	L"2010-03-29-15:36:30"
TIME_OF_DAY	none	L"Application.PlcProg.locVarTime "	L"15:36:30.123"

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the value(s) will be stored.
[in]	numElements	Number of WCHAR16 elements in 'data' available to read.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the value of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
WCHAR16 data[4096] = L"";
MLPIRESULT result = mlpiLogicReadVariableBySymbolString(connection, L"Application.PlcProg.x1", data, _countof(data));

MLPIRESULT mlpiLogicReadVariableBySymbolArrayBool8	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		BOOL8 *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of Boolean values (BOOL, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of BOOL8 elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
BOOL8 data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayBool8(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayChar	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		CHAR *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 8-bit signed values (SINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of CHAR elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
CHAR data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayChar(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayUchar	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		UCHAR *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 8-bit unsigned values (BYTE, USINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of UCHAR elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
UCHAR data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayUchar(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayShort	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		SHORT *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 16-bit signed values (INT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of SHORT elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
SHORT data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayShort(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayUshort	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		USHORT *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 16-bit unsigned values (WORD, UINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of USHORT elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
USHORT data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayUshort(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayLong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		LONG *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 32-bit signed values (DINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of LONG elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
LONG data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayLong(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayUlong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		ULONG *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 32-bit unsigned values (DWORD, UDINT, TIME, DATE, DATE_AND_TIME, ..., MlpiLogicType) from a variable. by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of ULONG elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
ULONG data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayUlong(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayLlong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		LLONG *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 64-bit signed values (LINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of LLONG elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
LLONG data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayLlong(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayUllong	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		ULLONG *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 64-bit unsigned values (LWORD, ULINT, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of ULLONG elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
ULLONG data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayUllong(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayFloat	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		FLOAT *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 32-bit floating point values (single precision, REAL, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of FLOAT elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
FLOAT data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayFloat(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayDouble	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		DOUBLE *	data,
		const ULONG	numElements,
		ULONG *	numElementsRet
	)

This function reads an array of 64-bit floating point values (double precision, LREAL, MlpiLogicType) from a variable by symbolic access.

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	numElements	Number of DOUBLE elements in 'data' available to read.
[out]	numElementsRet	Number of elements used.

Returns

Return value indicating success (>=0) or error (<0).

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
DOUBLE data[10];
ULONG numElementsRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayDouble(connection, L"Application.PlcProg.x1", data, _countof(data), &numElementsRet);

MLPIRESULT mlpiLogicReadVariableBySymbolArrayVoid	(	const MLPIHANDLE	connection,
		const WCHAR16 *	symbol,
		void *	data,
		const ULONG	dataSize,
		ULONG *	dataSizeRet
	)

This function reads user-defined data type values from a variable by symbolic access (raw reading).

Parameters

[in]	connection	Handle for multiple connections.
[in]	symbol	Symbol variable of PLC application.
[out]	data	Pointer to variable where the values will be stored.
[in]	dataSize	Number of bytes in 'data' available to read.
[out]	dataSizeRet	Number of bytes used.

Returns

Return value indicating success (>=0) or error (<0).

Note

It's highly recommended to use MLPI IEC data types (like MLPI_IEC_LREAL, MLPI_IEC_USINT, ... see mlpiGlobal.h) for an user defined structure.

Example:

// Read the values of the variable 'x1' in the program 'PlcProg' in an application called 'Application'.
DUT data;
ULONG dataSizeRet = 0;
memset(data, 0, sizeof(data));
MLPIRESULT result = mlpiLogicReadVariableBySymbolArrayVoid(connection, L"Application.PlcProg.x1", &data, sizeof(data), &dataSizeRet);