Burn Bootloader and Firmware on Ender3

Many of us, have an Ender 3 printer. It works amazing for an entry-level 3d printer. I got mine 2 years back with an 8-bit board and never felt any need to upgrade the firmware.

Until, I wanted to experiment with Octoprint but to my surprise, it does not support the stock firmware that comes with the 3D Printer. It is a must to upgrade the firmware to marlin...

I started with my research and noticed few hurdles that I needed to solve

• Cannot upgrade firmware over USB cable
• Need USB ISP or Arduino to update firmware
• Need a boot-loader, where to get that one from?
• Connections to board sound scary
• What if I brick my printer?
• All tutorials available were not up to date

So in this tutorial, I will share how to burn a bootloader using an Arduino nano and then upgrade the firmware using a USB cable directly connected to the printer. It sounds scary at first, but it is not.

I was pleasantly surprised by how simple and quick this was...

Software

• Arduino IDE
• Marlin 1.x source code
• Drivers for Arduino Nano
• Board manager for Sanguino
• u8Lib

Hardware

• Arduino Nano
• Jumper wire
• USB cable
• PC with Windows

• Before we start anything we need to get the details of the board
• To get the same open the 3d printer and take some close-up photos
• Mine was 1.1.4V with Atmega1284p 8-bit board
• Based on personal experience, I could not compile Marlin 2.x for my 8bit board. So I recommend using Marlin 1.x
• There is no separate software for the bootloader that one can find on the internet. It is included as part of Arduino ide ( with Sanguino board lib)

• Download the latest source code from https://github.com/MarlinFirmware/Configurations/tree/release-1.1.9
• Do not use Marlin 2.x for an 8-bit board
• Extract the Marlin firmware to C:\Temp\Marlin-1.1.x
• Download latest config files from https://github.com/MarlinFirmware/Configurations/tree/release-1.1.9/config/examples/Creality/Ender-3
• And paste them in folder C:\Temp\Marlin-1.1.x\Marlin and paste/overwrite config files
• Make sure that the config files are specific to ender3 only
• File names for reference
• Configuration_adv.h,
• Configuration.h,
• _Statusscreen.h and
• _Bootscreen.h

• Go to https://www.arduino.cc/en/software and download the latest ide based on your OS
• Connect the Arduino nano to the PC via a USB cable, in a few minutes the drivers for USB chip is automatically loaded
• Go to https://www.arduinolibraries.info/libraries/u8glib and download the latest lib zip
• In Arduino IDE Menu, "Sketch" > "Include Library" > "add .Zip Library", select the downloaded zip file and press open
• The u8glib library will be installed and added to ide
• In Arduino IDE Menu, "Files" > "Preferences", add additional board manager https://raw.githubusercontent.com/Lauszus/Sanguino/master/package_lauszus_sanguino_index.json
• Press OK/save and close the preferences window
• Under "Tools" > "Board" > "Board Manager", install sanguino board
• You may have to restart Arduino ide for all lib and boards to load
• Connect the 3d printer and PC using a USB cable, so that the usb drivers are also installed (optional)

• Disclaimer: Once you burn the bootloader, it will overwrite your current firmware.
• Connect Arduino nano to PC via a USB cable and burn ArduinoISP code on it
• Make connections as shown in the picture between ISP pinouts of the ender3 and nano
• Change the IDE settings
• Board: Sanguino
• Processor: ATmega1284p
• Port: Based on the com port detected
• Programer: ArduinoISP
• Under "Tools"> "Burn Bootloader"
• Within a few seconds the bootloader is written on the ender3 board
• Our bigger hurdle is now solved.
• Disconnect Arduino nano

• Connect ender 3 via a USB cable to your pc, in few minutes the latest driver for the USB / board i installed and ready for use
• Go to folder C:\Temp\Marlin-1.1.x\Marlin
• Open Marlin.ino, this, in turn, opens Arduino IDE.
• Verify files Configuration_adv.h and Configuration.h, are for ender3
• If you want recovery post power loss, enable it as shown
• Compile the firmware to make sure there are not errors
• If successful, write the new firmware to ender 3
• Disconnect the USB cable. restart the printer
• Initialize EPROM
• Voila we have Marlin firmware on our ender 3, ready to use

• The steps are easier than I originally thought
• The main hurdle is the bootloader, once that is solved, one can upgrade firmware anytime
• Marlin 2.x should not be used on old 8bit boards
• Marlin 1.1.9 is bit laggy and downgraded it to Marlin 1.1.4 from Creality's website https://www.creality3dofficial.com/pages/firmware-download
• I discovered that "Recover on power loss" in Marlin is buggy, even for completed prints, it gave me the option to resume print. So I disabled it and connected my printer on a UPS :)

Please share suggestions/feedback