Real Time Ethernet with Fast ADS

The Fast ADS protocol is based on Ethernet. In combination with TwinCAT, this bus system has real-time capability and reaches cycle times of < 1ms. The real-time Ethernet driver was developed for Windows 2000, Windows XP and Intel Ethernet chips.

Further information can be found at http://www.pc-control.net/pdf/022002/pcc_ethernet_e.pdf.

BK9000

On the BK9000 from firmware version B8 the Fast ADS protocol is implemented in parallel to the existing protocols. Simultaneous utilization is only possible, if the function ADS was selected in the System Manager (IP Address tab). If the function NoRealTimeFlag is not selected, communication is exclusively via Fast ADS.

With Fast ADS, the watchdog is set to 100 ms. If it is triggered (e.g. if TwinCAT stops), all other Ethernet services are usable again. The K-Bus works synchronous with the Fast ADS.

B900

RT-Ethernet respectively Fast ADS is implemented on all B900 modules. The task cycle time of the TwinCAT has to be smaller than 10ms. Otherwise the missing telegram will be interpreted as error and the outputs will be set to zero!

Settings at the System Manager

BK9000 tab

No Real Time Flag

With activated flag TCP/IP or UDP telegrams are also able to be received. But the Jitter of the real time telegrams increases!

K-Bus Reset

On the K-Bus a reset is released.

Data Exchange

This defines, after how many task cycles a telegram is to be sent to the Fieldbus Station (Bus Coupler / Fieldbus Box)
Modulo sets, in witch Task the telegram is to be sent. This enables to optimize the system performance.

Example: Divider 5 and Modulo 3 - after each 5th Task (in fact the 3rd) a telegram is sent.

VLAN

VLAN (virtual LANs) supporting Switches are able to prioritize incoming telegrams by this.

IP Address tab

Host Name

The name of the fieldbus station (Bus Coupler / Fieldbus Box) can be edited here.

IP Address

The IP-Address of the fieldbus station (Bus Coupler / Fieldbus Box) is to be set here.

GetHostByName

With this button, an IP address can (BK9000: from Firmware-Version B2) be taken from a DHCP-Server (Dynamic Host Configuration Protocol Server).

Set IP Address

With this button, the IP address is set via ARP.

AMS Address

Shows the AMS-Net ID of the fieldbus station (Bus Coupler / Fieldbus Box). It is automatically generated, by adding two extra byte values (".1.1") to the IP address.

BootP

This Checkbox is selectable, if the Beckhoff BootP Server is installed and started (from TwinCAT Version 2.8).

New MAC Addresses

With started Beckhoff BootP Server, the new MAC addresses (Media Access Controller addresses) can be displayed by clicking this button.
The new addresses are displayed in the field under the button.

If only one new fieldbus station was connected, accordingly only one new MAC address is displayed.
To this new MAC address a desired IP-address can be allocated in the field IP Address mentioned above.

If further fieldbus stations are connected, you can repeat this procedure on the tabs IP Address of this stations.

Communication Settings

Settings about communication via ADS or RAW.