ADS device identification

ADS-AmsNetId

It is not only possible to exchange data between TwinCAT modules on one PC, it is even possible to do so by ADS methods between multiple TwinCAT PC's on the network.

Every PC on the network can be uniquely identified by a TCP/IP address, such as "172.1.2.16". The AdsAmsNetId is an extension of the TCP/IP address and identifies a TwinCAT message router, e.g. "172.1.2.16.1.1". TwinCAT message routers exist on every TwinCAT PC, and on every Beckhoff BCxxxx bus controller (e.g. BC3100, BC8100, BC9000, ...).

Configuration:

The ADS-AmsNetId of a TwinCAT-PC can be set in the TwinCAT system service: A menu appears after the system service icon has been selected. By selecting "Properties" you reach the "TwinCAT System Properties" dialogue.

After the "AMS router" page has been selected, the desired identifier can be read or modified in the "AMS Net Id" field. By default, the TwinCAT installation constructs the AMSNetId from the TCP/IP address of the PC with an extension of ".1.1" (as if it were a "sub-net mask" for field busses, target bus controllers,..).

The AMSNetId can in fact be freely chosen.

When the services of an ADS device in the network are called on, its message router, or, more precisely, its AMSNetId, must be known. This is achieved through insertion of the target PC, because of which TwinCAT can establish the connection between the TCP/IP address of the target PC and the AMSNetId of the target message router address.

ADS-Port

The ADS devices in a TwinCAT message router are uniquely identified by a number referred to as the ADS-PortNr. For ADS devices this has a fixed specification, whereas pure ADS client applications (e.g. a visualization system) are allocated a variable ADS port number when they first access the message router.

The following ADS port numbers are already assigned: