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Problem with ModBus on S7-222


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Posted
Hi to all, i wrote a slave instruction on S7-222, the program downloaded to PLC without any problem. when im try to use modscan as master the messages i get are "MODBUS message TIME-OUT" and "Recieved Invalid Response to MODBUS Query", when im checking the BIT and byte for Done and error the results are: for Done=1 for Init block=5(5 Holding registers overlap Modbus Slave symbols) and for slave block=10(10 Slave function not enabled). i can see that modscan send request but PLC wont response. what does it mean every one of this errors? i attach the program i wrote if someone could check it and instruct me what to do, or to correct the problem. I'll keep trying to make it work!. Thank in advance for help. I very appreciate your help. Best Regards, Greg. mahteshim_Dryer_left_TEST.zip

Posted
You reserved memory VB69...VB848 for library, so you cant use these registers for data. in MODBUS_INIT put the first data byte at last input "HoldStart", not in the range of library memory; i.e. if your holding registers are VW1024, VW1026, ... put "&VB1024.
Posted
Hi, I already figured it out with exploring the Error description, but Thanks any way for paying attention and answering. Best Regards, Greg.

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