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Modbus communication not working after firmware downgrade
Dears All ,
We had a stand alone AC 800M controller with software version 5.1.0/1 , in order to integrate it is the 800xa DCS version 5.0.1/1 , we had to downgrade the firm ware and write a new logic in the 800XA version .
After the download of application the I/O cards are reading properly but the communication cards CI853 and CI867 are not working , the program and the settings are the same as written in the stand alone program of 5.1.0/1 ,
please advice how to bring CI853 back in service