Connecting Modbus RTU master to Modbus TCP slave about mbusd HOT 3 CLOSED

Hi @mgalemin
mbusd accesses a modbus RTU instance (i.e. reading its values) and provides a Modbus TCP server (serving the read out values).

For example, can mbusd work as a TCP client and connect to a remote TCP server?

I think that is exactly the other way around - right?

from mbusd.

NO, this won't work. You would need something that creates a map to begin with.
RTU master wants so send something to NODE 1. So it emits an RS-485 packet, addressing NODE 1.

Your gateways should know to listen to NODE 1, then it should know what TCP address NODE 1 is on.

You would need something like a translation map:

Node1, 192.168.11.1:502
Node2, 192.168.11.2:502

No such mapping exists in mbusd. The good news is, that you can put something together like this pretty easily using a library. I achieved a TCP:RTU mapping via j2mod (Java) where the Java host (Raspberry PI) is acting as an RTU slave for (near) real time sensors and acting as a TCP master for "slower" data requests (e.g. what's the temperature in the toilet).

Funny thing is that I use mbusd with this too, so the TCP request goes back to a serial link. The rationale in this, is that I can kill a master and start a developer master without pluggin 2-3 serial dongles over to an other host on the other side of a house.

from mbusd.

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

from mbusd.