USB3.2 backward compatibility details
USB3.2 backward compatibility details
I am confused by the behaviour of the USB3.2 ports on my new laptop and I would appreciate some advice. Long story short, every USB device works with my laptop except for some ESP32 devices with CP2102 USB chips. The ESP32's work on every other desktop or laptop I try so they are OK as well.
Now for the weird bit that makes absolutely no sense. If I plug in an unpowered USB hub first, the ESP32's will then work plugged into the hub and even plugged into a USB3.2 port on the laptop. Unplug the USB hub and the ESP32's disconnect just like if you unplugged them as well.
So, what wizardry is the USB hub performing? Does plugging a USB3 hub in make the laptop's internal USB hubs default back to USB3 protocol? I can carry the USB hub around just to make it work but I am sure it must be possible to make the ESP32's work without that. USB3.2 is supposed to be 100% backwards compatible but something is not working here.
It seems there might be an issue with the handshake protocol on your device. Inserting the hub could force a different mode since it handles negotiations correctly. I remember a hardware recall where resistors had to be replaced on every unit to support USB 3.0 when it replaced USB 2.0 on devices. That wasn't common when the hardware was originally built.