LabVIEW™ VIs

The TwinCAT 3 Interface for LabVIEW™ provides controls and VIs for use in LabVIEW™.

The VIs are located in the block diagram in the functions palette: Functions > User Libraries > Beckhoff-LabVIEW-Interface.

The main folder contains the basic VIs that can be used to build a program for reading via ADS, writing via ADS, TypeResolving and releasing the ADS client. In addition, the main folder contains the subfolders: Low-Level, With TypeResolving and Utilities.

Low-Level

The Low-Level subfolder contains Low-Level-VIs. The low-level VIs operate based the same principle as the basic VIs. The low-level VIs involve a little more programming effort but offer higher performance (in terms of data throughput) than the basic VIs and more flexibility for realizing complex programs. Reading with Polling Cycle is an example that uses low-level VIs for fast reading via ADS. Writing with polling cycle is a similar example. Not only reading and writing can be accelerated in this way, but also TypeResolving, see Continous Read, for example.

The table describes the subfolders and their contents and function:

Subfolder	VIs	Function
Init	Base Init	Initializes the ADS client.
	Get List of ReadWrite Symbols	Creates a list of ADS read and write symbols.
	Get List of Registered Targets	Creates a list of registered ADS target systems.
Read	Init Reader	Initializes the ADS Reader.
	Send Reader-Request	Sends a request to the ADS server.
	Register Notification	Registers the notification on the ADS server.
	TryReadData	Checks the response from the server and reads the data stream.
	Release Reader	Releases the reader from memory.
Write	Init Writer	Initializes the ADS Writer.
	Send Writer Request	Sends a request to the ADS server.
	CheckWriteStatus	Checks for the response from the ADS server to ascertain whether the data packet was received.
	Release Writer	Releases the writer from memory.
SumUp	Init SumUp	Initializes the ADS-SumUp.
	Add SubCommand	Adds a new command to the SumUp.
	Put Data	Puts new data to the initialized command that is to be written to TwinCAT.
	Get Data	Gets data from a SumUp command that was read from TwinCAT.
	Enable Autosend	Enables automatic sending of SumUp commands.
	Send SumpUp	Sends all SumUp commands to the TwinCAT runtime.
	Release SumUp	Releases the SumUp handle in the memory.
TypeResolver	Init Type	Initializes the TypeResolver.
	Resolve From TC Type	Converts the TwinCAT 3 data type to a LabVIEW™ data type variant.
	Resolve To TC Type	Converts the LabVIEW™ data type variant into a TwinCAT 3 data type.
	Release Type	Releases the TypeResolver from memory.

With TypeResolving

The With TypeResolving subfolder contains two VIs for reading and writing via ADS with integrated TypeResolver block.

Utilities

The Utilities subfolder contains additional VIs for the following purposes:

Subfolder	VIs	Function
Notification	ADS To LabVIEW Timestamp	Converts ADS timestamps to LabVIEW™ timestamps.
	Notification Data To Variant Array	Builds an array of LabVIEW™Variant from the notification data stream.
	Stop Notification	Stops the ADS notifications.
	Start Notification	Starts the ADS notifications.
	Unregister Notification	Unregisters the notification on the server.
LVBuffer	Init LVBuffer Handle	Initializes a handle for reading an ADS notification using the LabVIEW™-side data buffer.
	Read From LVBuffer	Reading data from the data buffer
	LVBuffer status	Reading the number of samples in the data buffer
	Release LVBuffer Handle	Releases the handle to the data buffer
Routes	Get Routes	Reads all target systems that are connected to the local TwinCAT system.
Routes	Get Route Info	Specifies all subsystems and ports for a target system.
CoE	Read CoE List	Reads a CoE directory of a terminal and lists the available CoE objects.
	Read CoE Description	Reads the description of a CoE object and specifies the sub-elements.
	Read CoE Entry	Reads an entry from a CoE directory and outputs the properties.
	Read CoE Value	Reads the value of a CoE entry.
	Write CoE Value	Writes the value of a CoE entry.
Project Automation	Init Project	Initializes a TwinCAT 3 engineering project. Either an existing project is opened or a new one is created.
	Create Task	Creates a task in a TwinCAT 3 project or changes the task parameters.
	Scan IO	Checks existing inputs and outputs on the target system and adds them to the project tree.
	Create PLC	Creates a PLC within a TwinCAT 3 project.
	Activate Solution	Activating a TwinCAT 3 project.
	Release Project	Releases the handle to the TwinCAT 3 project.
Heartbeat	Init Heartbeat	Creates a Heartbeat instance with a handle.
	Run Heartbeat	Starts connection monitoring.
	Stop Heartbeat	Stops connection monitoring.
	Release Heartbeat	Releases the handle to the Heartbeat instance from memory.
	Get RTD Estimate	Indicates the current estimate of the Round Trip Delay.
	Heartbeat	Initializes, starts and stops connection monitoring in a VI.
	Generate Type	Generates a corresponding constant or control with the LabVIEW™ data types for a symbol using the TypeInfo of the TypeResolver.
	Check License	Checks the license state on a given target system.
	Set Device State, Get Device State	Reads or changes the state of an ADS device.
	Get Version Info	Provides information regarding the product version.

Controls

The controls are located in the front panel in the controls palette under: User Controls > Beckhoff-LabVIEW-Interface.

The Notification subfolder contains controls that are required when initializing the LabVIEW™ event for ADS notifications.

Furthermore, the subfolder “TypeGenerator” contains TypeGenerator class objects to convert TwinCAT types into LabVIEW™ types (see Generate LabVIEW™ type).

The following table describes the function of the controls:

Subfolder	Controls	Function
Notification	Single User-Event Data	Control for initializing a LabVIEW™ event for Single ADS notifications.
Notification	Buffered User-Event Data	Control for initializing a LabVIEW™ event for Buffered ADS notifications.
TypeGenerator	CBase	Class object; base class of the TypeGenerator
	CBool	Class object; Boolean class of the TypeGenerator.
	CNumeric	Class object; numeric class of the TypeGenerator.
	CString	Class object; LabVIEW™ string class of the TypeGenerator.
	CArray	Class object; array class of the TypeGenerator.
	CTimestamp	Class object; LabVIEW™ timestamp class of the TypeGenerator.
	CCluster	Class object; LabVIEW™ cluster class of the TypeGenerator.

Further Information