I use Schneider M241 PLC with IDE SoMachine based on CODESYS v3.
For communication with PLC Modbus TCP and Codesys V3 ETH protocols are in use.
In PLC documentation I found that embeded Modbus TCP server is async with program execution. This mean that eny network variable can be changed in the middle of user program cycle. Small test confirm this. When I try to use Codesys V3 ETH protocol (via symbol export) simultaneously with Modbus TCP in my test - strange result produced. Via Modbus HMI sometime read variable value from the middle of the scan, but at the same time this HMI return value only between scan via Codesys V3 protocol.
When I try to ask Schneider support - they answer is "This is not our development, and we don't know is this protocol sync or async."
In documentation I don't find any decription or notes about this.
Question: Does any body know: is Codesys V3 ETH protocol for HMI/SCADA sync or async, or this is runtime dependet?
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I use Schneider M241 PLC with IDE SoMachine based on CODESYS v3.
For communication with PLC Modbus TCP and Codesys V3 ETH protocols are in use.
In PLC documentation I found that embeded Modbus TCP server is async with program execution. This mean that eny network variable can be changed in the middle of user program cycle. Small test confirm this. When I try to use Codesys V3 ETH protocol (via symbol export) simultaneously with Modbus TCP in my test - strange result produced. Via Modbus HMI sometime read variable value from the middle of the scan, but at the same time this HMI return value only between scan via Codesys V3 protocol.
When I try to ask Schneider support - they answer is "This is not our development, and we don't know is this protocol sync or async."
In documentation I don't find any decription or notes about this.
Question: Does any body know: is Codesys V3 ETH protocol for HMI/SCADA sync or async, or this is runtime dependet?
Does anybody use this protocol (Codesys IEC vars access) ?