--- title: "WIZ125SR how to differentiate the two UART" url: "https://maker.wiznet.io/forum/12282" markdown_url: "https://maker.wiznet.io/forum/12282/md" type: "Forum topic" category: "Serial-to-Ethernet & ConfigTool" author: "mat" created: "2017-05-12T08:24:36+09:00" last_activity: "2017-05-15T01:26:27+09:00" language: "en" views: 894 replies: 1 source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)" --- # WIZ125SR how to differentiate the two UART ## Question Asked by mat on 2017-05-12 in Serial-to-Ethernet & ConfigTool. Hello everyone ! I’m using an WIZ125SR to interfacing my computer with RS232 devices. I send the command through TCP with the computer, the WIZ125SR convert it into RS232, send it to the device, and I receive the response by the reverse path. My problem is: I do I differentiate the two UARTs ? Because when the connection begin with the computer, the sockets are ok, I can send data through the two sockets, but I don’t know to who I send the command ! And my two RS232 device are not the same. When I configure the wiznet with the tool given by wiznet, I set the port and address of each device, the IP address is the same, no choice, but the port not. And that is what I want. But when I check the two sockets, the two port are random at every new connection. Thank you for your help by advance ! ## Replies ### Reply 1 by irina, 2017-05-15 Hi Mat, ![](https://avatars.discourse-cdn.com/v4/letter/m/e9c0ed/48.png) mat: > I set the port and address of each device, the IP address is the same, no choice, but the port not. And that is what I want. But when I check the two sockets, the two port are random at every new connection. In general, for products supporting multiple UARTs such as WIZ120 / 125SR, it is possible to distinguish by setting different port numbers for each UART. If the UART has different port numbers but the data seems to be mixed, try performing a firmware update. The latest firmware of WIZ125SR is v1.4. --- Source: https://maker.wiznet.io/forum/12282