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Connect hotend to Raspberry

The hotend is shipped with Klipper V9 (EU Batch 1 machine) pre-installed but is connected to the CC-mainboard with a customized USB-C.

Physical Connection

The hotend uses USB-C at 24v but does NOT negotiates with standard USB protocol, thus CAN NOT be connected to other devices, and the CC-Mainboard's USB-C under NO CIRCUMSTANCES must be connected to any USB-C device. It's constant 24v and will instantly fry the client device.

Requirements

  • Random USB 2.0 A-type cable
  • USB-C breakout board (either 4 or 6 pin, doesn't matter)

Adapter Wiring

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NOTE Some USB cable doesn't have the negative (black) wire coated, and instead it's a free wire. If there are two free wires (silver + copper) one is the shielding, the negative can be found with a multimeter. On the above image the greay line represents the white cable, not the naked silver.

NOTE Some cheap chinese USB cable were spotted with white/green wires mixed up. If possible, confirm the cable colors with a multimeter. "Google USB Cable Colors" and "USB-A pins".

Klipper Connection

The hotend -still- won't connect properly on some Klipper install, as it's an ACM device. If you installe Klipper with the Pi-Imager tool, chances are you don't have the cdc-acm kernel module loaded. Doing it manually would require constantly SSH-ing in and running the command. To make the Linux automatically load it, we need to edit the /etc/modules file to include a new line cdc-acm, then reboot the Raspberry.

Klipper [mcu] Config

[mcu]
serial: /dev/ttyACM1
baud: 1000000
restart_method: command

To figure out your ttyACM device, SSH into the Raspberry and go to /dev. Run the command ls to list all files, and locate any file that's named ttyACM with a number at the end.

Outdated MCU error

Most likely you'll get an outdated MCU error with the MCU being V9, and your Klipper being up-to-date. Flashing the newest Klipper onto the hotend boards requires extra hardware and some soldering thin legs of the controller and it would break compatiblity with the factory mainboard.

ttyACMx constantly changing

TODO: Find solution