Beckhoff TwinCAT2/3 Ethernet Absolute

8 min

Review the following information for setting up and configuring the Beckhoff TwinCAT2/3 Ethernet Absolute driver. This driver replaces the Beckhoff TwinCAT3 Ethernet Absolute (Gen1.3) and Beckhoff TwinCAT2 Ethernet Absolute (Gen1.3) drivers.

Note: This driver is experimental. Some features might not work as expected.

Litmus Edge compatible series

Compatibility parameter	Compatible items
Driver type	Ethernet
Validated devices/series	Beckhoff TwinCAT2 Beckhoff TwinCAT3

The driver connects to the PLC as an ADS client over AMS/TCP. It reads and writes PLC variables, batching requests with ADS sum commands, and can browse the PLC symbol table, including arrays and structure members. Tags can be read in polling or subscribe mode.

To set up and configure this device in Litmus Edge, do the following:

Step 1: Set up and configure the PLC device

Step 2: Set up the PLC device in Litmus Edge DeviceHub

Step 3: Configure the list of registers

Step 1: Set up and configure the PLC device

If the device is configured for Ethernet access, find its network parameters. Otherwise, follow the steps below.

The PLC accepts connections only from systems in its route table. Add a route for Litmus Edge before you connect the device. The PLC rejects a connection whose Local AMS ID does not match a route.

Note: The Beckhoff PLC is also a PC with its own operating system, and you can set up its IP address in the same way as a PC.

To add a route on a TwinCAT3 PLC:

Note down the following information and refer to it as needed. Device: TwinCAT 3 Beckhoff PLC Communication I/F: Ethernet

Launch a new project in TcXaeShell.

Click Routes to add the target Litmus Edge that connects to the PLC.

Click Add... and configure the following parameters: Route Name (Target): Enter a name for the route. AmsNetId: Enter the AMS NetId for the route. If the PLC is running as a soft connection, and Litmus Edge and the panel PC are on the same network, the AmsNetId and Address Info values are the same, with .1.1 at the end. Transport Type: Review and confirm the transport type for the route. Address Info: Enter the IP address of the target Litmus Edge in the network. Target Route: Select Static.

Click the Restart TwinCAT icon. Then, click the Login icon to start the PLC runtime.

Step 2: Set up the PLC device in Litmus Edge DeviceHub

Configure the following parameters when you Connect a DeviceConnect a Device with this driver. Update default values to the specific setup of your device.

Parameter	Value
Device Type	Beckhoff
Driver Name	Beckhoff TwinCAT2/3 Ethernet Absolute
NetworkAddress	The IP address of the PLC you defined in Step 1. Default value 192.168.0.1
NetworkPort	The TCP port of the PLC. This must match the port configured on the PLC. Default value 48898
AdsPort	The ADS port of the PLC runtime: - TwinCAT3: 851 for PLC runtime 1. Use 852, 853, or 854 for runtimes 2 to 4. - TwinCAT2: 801 Default value 851
LocalAmsId	The AMS NetId of the Litmus Edge device: [Litmus Edge IP address].1.1 For example, if the Litmus Edge IP address is 192.168.0.152, enter 192.168.0.152.1.1. This value must match a route on the PLC. Default value 0.0.0.0.1.1

The following parameters are under Advanced Parameters.

Parameter	Value
AmsId	The AMS NetId of the PLC, as six dotted octets, for example 172.16.17.10.1.1. If you leave it empty, Litmus Edge uses the PLC's IP address with .1.1 at the end. This is correct only when the PLC's AMS NetId matches its IP address.
MaxRequestSize	The maximum number of bytes retrieved in one request. Enter a value from 128 to 65536. Default value 4096
ReadTimeout	How long the driver waits for a response, in milliseconds. Enter a value from 1000 to 60000. Default value 5000

For the Meta Data, Status Register, and Optional Settings options, see Connect a DeviceConnect a Device.

Step 3: Configure the list of registers

When you Add a TagAdd a Tag to the connected device, see the following register table and tag parameters.

You can also Browse and Add Tags from a DeviceBrowse and Add Tags from a Device for this device. Browsing is the most reliable way to add tags, because it uses the addresses defined in the PLC.

See the following additional resources if necessary:

Organize Device and Tag Data by Using MetadataOrganize Device and Tag Data by Using Metadata

Tag Formula VariablesTag Formula Variables

Register table

A tag address is a memory class and a 0-based offset. The driver passes the offset to the PLC as you enter it.

A BOOL tag in the M, I, or Q class reads the bit image, so its address is a bit offset.

Every other class and value type uses a byte offset.

Name	Description	Access Type	Address Format	Max Address
D	Data	R/W	DDDDDDDDDD	2147483647
M	Memory	R/W	DDDDDDDDDD	2147483647
R	Retain	R/W	DDDDDDDDDD	2147483647
I	Input	R/W	DDDDDDDDDD	2147483647
Q	Output	R/W	DDDDDDDDDD	2147483647

All five classes support the following value types:

BOOL

SINT

BYTE

WORD

DINT

DWORD

LINT

LWORD

REAL

LREAL

STRING

WSTRING

TIME

LTIME

DATE

DATEANDTIME

TIMEOFDAY

Tag parameters

Name: Select a memory class from the drop-down list: D, M, R, I, or Q. To read symbolic tags with this driver use D - DATA register.

Value Type: Select a data type from the drop-down list.

Address: For I, Q and M registers enter the address for the particular tag as defined in the PLC Software which matches the Index offset number of that tag. For symbolic tags enter Index offset number in the address field. See the Register table section for when to use a bit or byte offset. To avoid incorrect configuration, it is better to browse and add tags. Driver supports browsing

Polling Interval: Enter how often the tag polls for data, in seconds. Enter 0 to disable polling.

Tag Name: Enter a name for the tag.

Description (Optional): Enter a description for the tag.

The following parameters are under Advanced Parameters:

Communication mode: Select Polling or Subscribe. Default value Polling.

Index group: Leave this at 0 to use the default index group for the memory class. Any other value overrides it.