Additional Configuration for PLC-Task Synchronisation

CANopen® allows the generation of a synchronized process image by using the standard CANopen® SYNC-Telegram. The functionality described below is available from:

PLC Version:            V1.3.0

Communication Module Version:       V1.100 10.02.2009

A dedicated PLC-Task can be synchronized to the CAN-SYNC cycle. Any CANopen® process image used by this task is synchronized as well. The process flow is represented by the image below:

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The SYNC cycle time has to be large enough to accommodate

  • all synchronized data-exchanges on the bus (only applies to the synchronized master and slaves).
  • the PLC-Task program execution time. The time duration required by the task can be checked online in the CoDeSys task configuration.

Note

The tasks which are triggered with the CANsync interrupt have to be a higher priority than tasks which are running cyclically.

Note

If other communication modules are attached to the same CPU, the MIN_UPDATE_TIME of those communication modules must be larger than the MIN_UPDATE_TIME of the CANsync communication module.

Note

The online overview of the task configuration within CoDeSys will display implausible values of the CANsync task. This will not influence the functionality.

These additional steps have to be taken in configuring the PLC:

  1. Set the MIN_UPDATE_TIME for the specific Communication Module to 0 418de4f7e38b8d080a33139000473a6a_5aad49a2e38b825e0a33139000eba54e

  2. Configure a PLC-Task to run as interrupt task controlled by the specific Communication Module: Ext_Communication ModuleX_InputAny, where X is the CANopen®Communication Module slot. 418de4f7e38b8d080a33139000473a6a_17039037e38b82ac0a33139000eba54e