Got an old RPIzero you picked up awhile back to hit the limit for free shipping? Put that thing to use and get a great light weight, low cost klipper interface in the process. (helpful links and commands at the bottom)

If you like what you see and want to help support the channel
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https://www.buymeacoffee.com/Nero3dp
Looking for a great first 3d printer? Grab an Ender 3 V2 from the affiliate link below, get a great deal on a machine AND help the channel out in the process.
https://www.banggood.com/custlink/vmK...
Need filament or a printer? Purchase anything from MatterHackers with the link below and a portion of the sale goes to supporting the channel
http://www.matterhackers.com?aff=7543
I NOW HAVE A TWITTER, follow me @   / 3dpnero  

Resources:
https://community.octoprint.org/t/sim...
https://github.com/KevinOConnor/klipp...

1. Swapping ports used by GPIO and Bluetooth
sudo nano /boot/config.txt
Move the cursor to the very end and add:
dtoverlay=pi3miniuartbt

2. Disabling the serial console
sudo nano /boot/cmdline.txt
Look for following string (text) and delete it
console=serial0,115200

3. Raspiconfig stuff
sudo raspiconfig
Go to 'Interfacing Options'
Then P6 Serial
Then No
Then Yes
Then go down to finish and reboot.

4. Rebuild your Klipper MCU firmware, unselecting "Use USB for communication (instead of serial). Flash updated firmware to your board

5. Update your printer.cfg:
serial: /dev/ttyAMA0