cjh
Member
Question about MODBUS TCP gateways:
If you send a unit identifier value of 0 to a MODBUS TCP gateway, should you wait for a reply?
The spec. is kind of confusing here to me. I know that in a serial MODBUS RTU network, you don't wait for a reply when you do a broadcast but the MODBUS TCP spec. says that a unit identifier of 0 is valid either when you are sending a message to a gateway or to a standard MODBUS TCP server device.
It probably seems trivial but the throughput will definitely be affected if I wait for a reply and no reply is forthcoming (have to wait the entire timeout period). I know that I can buy a gateway to find this out but I was hoping someone here might know the answer and save me a few bucks...
If you send a unit identifier value of 0 to a MODBUS TCP gateway, should you wait for a reply?
The spec. is kind of confusing here to me. I know that in a serial MODBUS RTU network, you don't wait for a reply when you do a broadcast but the MODBUS TCP spec. says that a unit identifier of 0 is valid either when you are sending a message to a gateway or to a standard MODBUS TCP server device.
It probably seems trivial but the throughput will definitely be affected if I wait for a reply and no reply is forthcoming (have to wait the entire timeout period). I know that I can buy a gateway to find this out but I was hoping someone here might know the answer and save me a few bucks...