Using a USB-Serial adapter to control devices via Wi-fi

I want to be able to plug my Keyspan USB to Serial adapter into my router and control a RS232 deivice over the WiFi using a Windows laptop.

I'm using a GL-iNET router running the current 3.203

I found and installed kmod-usb-serial-keyspan plugin from the repository and it seems to have automatically installed other plugins that I assume it relies on.

Now when I plug it into the router, if I'm in the "Internet" tab, it seems to get detected as a 3G/4G Modem? Not sure if that's right but if I go to manual settup it seems mounted as /dev/ttyUSB0 which I think is right for a serial device??

Then under service, I can only choose LTE/UMTS/GPRS or CDMA/EVDO. I would assume neither of these are correct because it not actually a 3G/4G modem....

I've done lots of Googling and tried searching the forums but I'm just not getting the next step, the most similar I found was this;

But it seemed more about getting the adapter to mount, plus I have no idea how to open a terminal window on the router anyway, I tried via the browser and also using putty.

I also would assume for my laptop to find the adapter via the WiFi I'd need some software running on my laptop to mount it as a device?

What am I missing?

Does that adapter have any linux drivers at all?
Do you have those drivers in OpenWRT?

A lot of knowledge in all digital communication technology that has ever been invented.

This is OpenWRT forum. You are probably not running OpenWRT, since current OpenWRT version is 21.02 and version 3.203 never existed (AFAIK).

As I said, I’ve installed a plugin that seems specifically written for this adapter. Is that not a driver written for openwrt?

Okay, I thought it was a variant of openwrt but I’ll look into that now

it is, but it's not our variant ....

Okay but would that be the reason I’m having trouble with this particular issue?

Should I be expecting the adapter to suddenly appear in device manager when I plug it into the router?

missing sw support, but we wouldn't really know, since it's not our version of openwrt.

No, but you should see it detected in dmesg / kernel log.

Okay, slightly embarrassed as I bricked it when trying to put openwrt on it from this website. I recovered it with uboot, got it back to where I was and when I log in via ssh i see it’s running OpenWrt 19.07.7

I still can get my head around how even once the router has mounted the adapter, how does the windows laptop see the RS232 device over the network?

I’ve had USB network servers in the past that need software running on the laptop to detect and mount the USB device as if it’s locally connected.

Am I missing some accompanying software?

why would the laptop see the adapter ?

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Exactly, that’s why I think I’m missing something

i think you need to tell us what you want to achieve ....

You are expecting to plug in a device into a Linux router and then that device to automatically appear in Device Manager on a Windows laptop? That would be the biggest security / privacy / usability / ownership / control issue in all computing history! :rofl:
But I guess you are at least partially correct. That's where we're heading, seeing how dbus & systemd connects everything in Linux and Windows integrates Linux.
Sorry to dissapoint, we're not there yet. Just wait 10 more years... OpenWRT will have this "feature" too.

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There are various different pieces of equipment that I want to connect to via their own specific control software, all different manufacturers and software from Dolby equipment to Sony equipment that needs null modem adapters etc.

The USB adapter locally works fine with these devices but I want to use the adapter via the USB port in the router.

I was hoping these drivers would somehow allow this.

On the Linux side, it's doable, but the issue will be the serial port drivers in win10, that need to fake a serial port.

Right, so I’d need some Windows software that would detect the adapter connected to the router

no, it will not happen any time soon.

AFAIK there's no technology to serve a serial port towards Win10, and make it usable, and as always, it's a win10 issue :wink:

there are 3rd party solution, doing this, but those are commercial products.

No. You need a Windows driver that creates a virtual serial port and can send/receive data to/from a network connection instead of a physical serial port.

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How can you be so sure? Upnp / ssdp just need a very minor extension...


Currently I have a USB network server that can do this on the LAN and then I access it via the Wi-fi router, I was hoping I could cut down on kit. It must be possible but just not this way, shame.

Thanks for all your help and advice.