BECKHOFF CP-Link3 - Manual (Page 8)

Page 8
communication channel (RT Ethernet), so ensuring deterministic cycle times.
Virtual Serial Ports
The client's serial interfaces can also be used through a virtual serial port that is created for this purpose on the host PC.
This allows devices with serial interface to be connected to a client, and to be used by applications or by drivers in the
host PC. Communication between the virtual serial interface on the host PC and the actual serial interface on the client
again takes place here over a normal TCP/IP connection.
Virtual Graphics
One or more virtual graphic adapters are installed in the host PC in order to transmit the screen contents. There is a
distinction to be made between CP-Link 3 - Mirror Devices and CP-Link 3 - Extended Desktop Devices. A CP-Link 3 -
Mirror Device captures the screen content from the standard display device, and transmits it to one or more clients. The
standard display device is the one that is used initially when the Windows operating system boots up. A CP-Link 3 -
Extended Desktop Device extends the host PC's Windows desktop with an additional display device, whose screen
content can be transmitted to one or more clients. An application's program window can be moved to the additional
screens of the extended desktop. A CP-Link 3 client can thus either display the content of any of the CP-Link 3 -
Extended Desktop Devices or the contents of the standard display device. The contents of other display devices (e.g. of
additional graphics cards) cannot be displayed on CP-Link 3 clients.
The image data may optionally be transmitted via TCP/IP or via UDP/IP (Multicast). The advantage of Multicast is that
data can be transmitted simultaneously to a number of clients, without multiplying the transmitter bandwidth by the
number of receivers.
Note
A maximum of 10 display devices is possible under Windows 7 / Windows XP
The total number of 10 display devices cannot be exceeded, and this includes the
graphics cards installed in hardware, to which one or more display devices, depending
on the type (single or dual head) can be connected. A CP-Link 3 - Extended Desktop
Device corresponds to a single head graphics card, and thus to one display device.
Up to nine CP-Link 3 - Extended Desktop Devices can therefore be installed when a single head graphics card is used. If
a dual head graphics card is used, only eight CP-Link 3 - Extended Desktop Devices can be installed.