error writing to value.value: Bad_GatewayCommOff
how to solve this issue for HR8.1 write
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i did the changes as mentioned in the video but still same issue
This indicates that you are in read-only mode in the designer.
i changed to read/write in the designer. can you please provide the steps if any to cross verify ?
What does the message say now? Perhaps show a screenshot?
Error writing to value.value: Bad
Show us how you have set up your tag. This above is incorrect.
Consider the below OPC Address:
ns=1,s=[device]1.HR8 this would get you the whole word, you cannot get one bit out of a holding register unless you have a specific type of modbus device.
Either use the Siemens Driver with your S7-1200, or read up on how to use the Modbus driver.
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[MB]HR8.0 this was the OPC address in this same format i am able to read the bool data but write bool date to PLC throwing the above error
Siemens does not support writing to the Holding Registers in this way. I suggest you use the Siemens driver instead.
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I understand but I wanted to use Mobbus TCP for Modbus TCP simulation attack.
is any other way to write bool tag in S71200?
Use Coils (Modbus calls Booleans Coils thanks to a bunch of history)
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it meant both coil and HR cannot be use for writing ?
I believe you are right.
I don't understand what you mean by this?
Modbus is not native for talking to this PLC, why not use a normal method?
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