Although there are countless entries about the Octoprint and Ender 3, I still don't get my problem solved and therefore ask for your help. PLEASE!
I use a Creality Ender 3 and have already been able to print successfully with it. Now I wanted to connect a Raspberry Pi 3 and print a little more comfortably via Octoprint.
The setup of the Raspberry Pi seems to have worked well. I was able to flash it and I can also access the Pi via PuTTY. I updated the Pi accordingly. All of this worked fine over WiFi. I was also able to set up Octoprint and I can also access the Raspberry Pi via Octoprint.
I then connected the Pi to the Ender 3 using a USB cable, but unfortunately no connection is possible. The settings are on "AUTO". No port can be selected. I tried all of the baud rates without success.
The printer says it is running with Marlin 1.0.1 if this might be important.
I am using a proper power supply and there is no warning shown in Octoprint.
Can someone tell me what to check next? Do i need to check the log files or did i miss something obvious?