Beckhoff CX8190, Manual

Page: 57 / 72

Ethernet X001 Interface
CX8190 57 Version: 1.5
8.3 ADS-Communication
The ADS protocol (ADS: Automation Device Specification) is a transport layer within the TwinCAT system. It
was developed for data exchange between the different software modules, for instance the communication
between the NC and the PLC. This protocol enables communication with other tools from any point within
the TwinCAT. If it is necessary to communicate with another PC or device, the ADS protocol is used on top
of TCP/IP. Within a networked system it is thus possible to reach all data from any point.
Fig. 15: The ADS protocol as a transport layer within TwinCAT.
The ADS protocol runs on top of the TCP/IP or UDP/IP protocols. It allows the user within the Beckhoff
system to use almost any connecting route to communicate with all the connected devices and to
parameterize them. Outside the Beckhoff system a variety of methods are available to exchange data with
other software tools.
Software interfaces
ADS-OCX
The ADS-OCX is an Active-X component. It offers a standard interface to, for instance, Visual Basic, Delphi,
etc.
ADS-DLL
You can link the ADS-DLL (DLL: Dynamic Link Library) into your C program.
OPC
The OPC interface is a standardized interface for communication used in automation technology. Beckhoff
offer an OPC server for this purpose.
Protocol
The ADS functions provide a method for accessing the Bus Coupler information directly from the PC. ADS
function blocks can be used in TwinCAT for this. The function blocks are contained in the
Tc2_System.lib
library. It is also equally possible to call the ADS functions from AdsOCX, ADSDLL or OPC.