RS-485
An industrial-oriented serial standard, RS-485 operates on two wires using half-duplex signal. The wires are called A and B, sometimes also - and +. Very similar to RS-232 except for voltage and resistance tolerances, which are much higher on RS-485 making it ideal for harsh conditions that the bikes might experience outdoors.
The bikes use the protocol to communicate between battery BMS, motor controller and dashboard.
This protocol was used on all older models such as CUX, TC and TSX.
Service cable
Super Soco provides an official service cable to connect to both motor controller and battery. This official cable has two USB connectors, one Battery connector#Gen 1 and one female 30pin connector for the controller (with only 4 pins used).
One of the USB connectors leads to U-TEK UT-890A USB-serial converter that is responsible for the RS-485 communication while the other is just used to provide 5V power to the controller. The data pins on it are not connected.
Since the whole cable is just 5V power and RS-485 interface, it could easily be replaced by something like this, which could provide both the RS-485 and the 5V power from a single USB connector, provided that you end it by the correct Super Soco connectors.