Does anyone use Dragon Link telemetry with USB?

The Dragon Link telemetry question is this second.

I operated the Dragon Link telemetry via Bluetooth.
This seemed to work well but was very unstable.

So I thought of USB.
But this is very difficult.
It seems to be a communication, but I can not get any parameters at all.

I think that RX and TX are communicating well, considering that Bluetooth works without any problems.

So if you just enable usb function, you thought you could see the information of fc through MP without problems, but it is not at all.

Are you using the DragonLink telemetry feature via usb?

Please help me.

param rx1