Firmware opentx (2.3) on both.
When X7 connected via USB cable, QX7 is determined, assigned, works well.
When I connect the Jumper T12 via USB cable, there is no reaction from the computer OS.
On another "driver skilled"

Questions:
I checked the connection of SOME (not all) contacts from the cable to the soldering points of the USB connector on the T12 board.
But I didn't have time to check everything. Show most go on at evening.
1. what could be?
My versions are -
A. damage of USB protection circuits
B. damage of relevant ports of the MCU
2. I am looking for a connection diagram from USB to STM32F205VE5 for a generic case.
3. Looking for a circuit diagram from the USB connector to the MCU ports for this T12 radio