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Have a look in the link below:
https://kunbus-gmbh.atlassian.net/servicedesk/customer/portal/1/article/2379186179?src=-1420129237

Is there …?

Is there a practical example of putting a Modbus client into operation?

Take a look at this wonderful troubleshooting as an example of how it works:

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Is there an industrial switch I can use with a Revolution Pi module?

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