Hi, I like this solution, but in this case, what data type are the variables (e.g. idbModbusMaster)? If it is P2P_MB_BASE type, then you don't need #idbModbusMaster".MB_DB" at the end. Could you provide more detailed information about your solution?

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Split from Modbus Comm Load do not accept Modbus Master DB.

I tried to write the script you wrote, but I ran into a syntax error.
My experience is that when querying MODBUS, if there are multiple query blocks, the Modbus_Com_Load_DB block must be executed (Req) always with the current MD_DB reference, which is what I wanted with your solution.
idModbusMaster -> P2P_MB_BASE

Thank you for your help!

Basically I misunderstood your help. I thought you were using that script to cyclically call the MODBUS_Com_Load block with different parameters. 

Of course, it is not customary to call the MODBUS_Com_LOad block cyclically, but due to a wrong line of thought, I tried to do this. 

My problem was the MD_DB reference, because I mistakenly used multiple Modbus_Master_DBs. I wanted to always run a unique Modbus_Com_Load block for these so that the MB_DB reference would be correct for the current MODBUS_Master block.

I solved it correctly by running Modbus_Com_load once (FirstScan) and using only one Modbus_Master_DB, which I re-parameterize before each new query, thus realizing that multiple queries can be sent to multiple slave devices on the same serial line.