# 750-8000 Modbus TCP Issue to 750-362 **URL:** \ **Category:** CODESYS\ **Created:** [December 30, 2024, 6:09pm UTC](https://www.wago.community/t/750-8000-modbus-tcp-issue-to-750-362/1451 "2024-12-30T18:09:00Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![AdamKosick](https://avatars.discourse-cdn.com/v4/letter/a/cab0a1/32.png) [@AdamKosick](https://www.wago.community/u/AdamKosick)\ **Post date:** [December 30, 2024, 6:09pm UTC](https://www.wago.community/t/750-8000-modbus-tcp-issue-to-750-362/1451/1 "2024-12-30T18:09:00Z")
I am having an issue getting the 750-8000 basic controller to talk to a modbus fieldbus coupler 750-362. I have used modbus software on my pc and confirmed I can talk to the coupler. I wiresharked the controller and it doesnt even attempt to send out a modbus request. That status of the TCP slave says that it is “running” in codesys 3.5 but that the status is “connecting”. The log shows that I have a Socket\_Recv() error and sometimes reports an error 6. I have tried it with a brand new project too with exactly the same issue. IP addresses are 192.168.1.0 for the controller and 192.168.1.1 for the coupler with a subnet mask of 255.255.255.0 I even tried a gateway of 192.168.1.10 through a couple wago 758-918 gateways. it definitely looks like its the controller thats the issue here. any help would be greatly appreciated. I have tested the fieldbus coupler with another PFC200 that I have and it works fine. There is some issue with the modbus tcp on the Basic Controller. ---
**Author:** ![JohnDitter](https://sea2.discourse-cdn.com/flex016/user_avatar/www.wago.community/johnditter/32/68_2.png) [@JohnDitter](https://www.wago.community/u/JohnDitter)\ **Post date:** [December 31, 2024, 6:48pm UTC](https://www.wago.community/t/750-8000-modbus-tcp-issue-to-750-362/1451/2 "2024-12-31T18:48:47Z")
Change the IP address of the 750-8000 to something like **192.168.1.2** instead of **192.168.1.0**. **192.168.1.0** is not typically a valid IP address for a network device because it is reserved as the **network address** in the **192.168.1.0/24** subnet. Make sure to change the address of the MODBUS master in CODESYS too. It should work then. ---
**Author:** ![AdamKosick](https://avatars.discourse-cdn.com/v4/letter/a/cab0a1/32.png) [@AdamKosick](https://www.wago.community/u/AdamKosick)\ **Post date:** [December 31, 2024, 8:03pm UTC](https://www.wago.community/t/750-8000-modbus-tcp-issue-to-750-362/1451/3 "2024-12-31T20:03:24Z")
Hey John, Thanks! This worked perfectly! I can’t believe I spent so much time on this. Very much appreciated. Adam Kosick