This problem is solved now. The following instruction needs to be updated: https://docs.m5stack.com/#/en/quick_start/unitv/v_function The instruction does not specify what driver is needed to communicate with hardware. It came out that the user needs a different driver than the one used for M5Stack core products. In case anyone has the same problem, please make sure you have the newest VCP driver by FDTI installed on your machine. My advice is to use their website to check out the latest version: https://www.ftdichip.com/Drivers/VCP.htm