OctoPi to Lerdge S board


Can I connect my Pi to a lerdge S board with a USB 3.0 to USB 3.0 cable? because it does not seem to pic it up in the port.

This is my first try and it keeps giving me: " Error: Failed to autodetect serial port, please set it manually." error.
I cannot change the serial port from AUTO. there are no other options?

I am using Latest octopi with a TEVO TORNADO printer but a LERDGE S motherboard.


The Raspberry Pi series appear to have USB 2.0 as the specification, to the best of my knowledge. I'm not exactly sure what a USB 3.0 cable is, to be honest. The 2.0-versus-3.0 is the speed of the upper limit. As for as I know, only the chips on each end (the Raspi or the RAMPS board) are specified with a version like this rather than the cable.

Go to OctoPrint -> Settings -> Serial Connection and change the baudrate to 115200 instead of AUTO. In the Serial Port pull-down, see if there is a device of some kind that you can select.

Update: it sounds like USB 3.0 cables have more pins.


@Thomas_Oosthuizen No point using a USB 3 cable, the pi only has USB2 ports. The pi 3 has a usb 3 controller, but that only really helps for what's on the onboard channels (such as the wifi controller). You should still be able to use your USB3 device, but it will be operating at USB2 speeds.

@OutsourcedGuru USB 3 cable have more wires in them. If you look closely at a connector, it will have the 4 pins you would expect to see, but if you look further into the connector, there are more pins at the back. Usually the USB3 cables are colour coded with a blue connector.


I did change the Baudrate but the serial port does not seem to change fro. Auto at all. I just had a isb 3.0. I thought it wouldnt matter as long as it is usb to usb


@jubaleth I did not know that. More info I actually have some USB cables with the blue tongues in them. I wish somebody would have talked about this earlier.

As suggested, I have to assume that plugging a USB 3.0 cable into a Raspberry Pi 3B of any flavor would result in backward compatibility with 2.0 speeds.

There's at least one Raspi competitor which uses 3.0 however:

  • LattePanda Alpha 864
  • NanoPi Neo4
  • RockPi 4
  • NanoPi M4
  • MinnowBoard Turbot Dual Ethernet Quad-Core