USB Serial over VPN
With "Expose a local USB device to VPN" the controller makes a connected USB serial adapter available as a TCP port. This lets you remotely program bus systems whose configuration software needs direct serial access — just as if the adapter were plugged into your own computer.
The share is reachable via the Direct-VPN, the Support VPN and on the local network.
Enable the share
Open the VPN page and click "Expose a local USB device to VPN".
Select the serial port (the USB adapter), the baudrate (must match the connected hardware) and the TCP port (default: 3001).
After saving, the overview shows the state of the share: Running, Connected or Adapter not connected.
Set up the client on Windows
On Windows you create a virtual COM port that points at the controller's TCP port — for example with the free HW VSP3 (single-port edition, hw-group.com):
Download and install HW VSP3 (the "Standalone" edition).
On the "Virtual Serial Port" tab choose a free COM port (e.g. COM5), enter the controller's VPN IP address as IP Address and the configured TCP port (default: 3001) as Port.
On the "Settings" tab disable "NVT enabled" — the connection uses raw TCP.
Click "Create COM" to create the virtual COM port.
Then select the new COM port in your programming software and configure the same baudrate as in the share (data format 8N1).
Set up the client on macOS / Linux
On macOS and Linux, socat does the job (macOS: install with brew install socat):
While the command is running, /tmp/ttyNOMOS is available as a serial port and can be selected in the programming software.
Notes
One connection at a time — disconnect the client before another one connects.
The baudrate of the share must match the connected hardware (data format 8N1).
The USB adapter must be plugged into the controller — the status indicator in the overview shows the current state.
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