USR-TCP232-304 Serial RS485 to TCP/IP Ethernet Server Converter Module with Built-in Webpage DHCP/DNS Supported

I use these to master Modbus-RS485 devices. Note it is a simple converter device - so it doesn't convert Modbus-TCP to Modbus-serial. This meant I had to code a Modbus-TCP-RTU master - which has some problems as responses in Modbus-RTU do not contain a transaction ID. If I repeat the same function code to the same slave with the same register count, the responses could get mixed up - my solution was to never do this (interleave requests with different register counts & checking response length resolves this issue). (This is a limitation of the Modbus protocol - not this device).I currently have two communicating to two different Modbus networks using different serial comms parameters - both have been running for prolonged periods without issue.

I would love to give this product 5 stars but the reality is that I have spent 7 hours trying to get it to work and still can't. 1. There are no instructions on the amazon page, why not provide a link to some? 2. I finally did find the manufacturers page and the product they provide, but the instructions simply don't work. I followed what they said and could not connect to the device either via Ethernet cable, or via Serial connection. I wrote to their "hotline" on whatsapp to get some help but received no response. So, in all, it seems I've wasted a bit of money and a lot of time.

Spent a while getting this working.. it's not well documented at all, as another poster mentioned.I bought it because it advertised AT command set but what it supports is utterly unlike anything you would call that,, resembling AT commands only in that they start with the letters 'AT'. There's not even a dial function.. Not managed to connect this to anything but that might be because the documentation is trash.Alas wasted money.

Have used many of the USR-TCP232-304 and TCP232-302 devices over the past 6 years for systems connected to cloud based servers.