Hi,

I would like to introduce myself to the members of the forum.

Is there any way in CoDeSys of defining and maintaining data consistency

on the ProfibusDP while transfering a package of bytes?

STEP7 for example supplies two system functions SFC14 and SFC15, which do the job. I don´t think, that SYNC and FREEZE alone will do it.

Does anyone have any experience?

Greetings,

Andy

I can't see any form for error-checking support natively in the Profibus protocol, but if possible for both master/slave, you could implement your own checking routine using e.g. CRC8 or CRC16. I would recommend using a lookup-table in that case. Example:

Implementation:

SendPacket(pointer to MyPacket to be sent, pointer to profibus packet, sizeof MyPacket, sizeof profibus packet)

  - Copies profibus packet data to custom packet.

  - Generates checksum and adds this to end of custom packet.

ProcessPacket(pointer to received MyPacket, sizeof MyPacket)

  - Returns True if no error, False otherwise.

Hope this helps.