This repository reflects my work on the EasyThreeD K7 3D printer. The K7 printer has been sold with either an 8-bit or 32-bit board, with the latter appearing in more recent purchases. My printer has the 32-bit board 'ET4000+', which is shared by the Nano and Dora printers from the same manufacturer, and so these files only apply to that model.

If you have a K7 with the ET-4000-V2 board, please see https://github.com/tux-friend/Easythreed-K7-ET-4000-V2

The board's bootloader is proprietary by MKS, which reads a binary firmware file mksLite.bin from the SD card on boot. After a short time (<30s) the firmware is written to the board, and the files on the SD card renamed *.CUR.

This is a clone of Marlin 2.0.9.1, modified to include the button functionality for the EasyThreeD K7/Nano. Button functionality is applied as a /feature, and has been merged into the 2.0.9.2 bugfix release. Unfortunately there seems to be layer shift issue when using the later version, so this repo will remain on 2.0.9.1 for the time being.

For the original firmware source and binaries based on Marlin 1.1.1 supplied by the manufacturer, see https://github.com/schmttc/EasyThreeD-K7-STM32/tree/Original-Firmware-Marlin-1.1.1

For additional files including compiled binaries, see https://github.com/schmttc/EasyThreeD-K7-STM32/tree/Additional-Files

• Compile using PlatformIO, board "mks_robin_lite" (From Marlin 2.0.9.2 use mks_robin_lite_maple)
• Physical buttons and LED currently are functional as per standrd behaviour
• Start button LED (improved feedback)
  • LED blinks slowly when printing/processing
  • When paused blinks LED quickly
  • LED is on when job is cancelled or completed
• Home button and filament feed/retract slider working
• Long press print button to raise print head 10mm while not printing
• Short press print button to print most recent file on SD card
• Serial baud rate is set to 115200, matching the original firmware

Marlin 2.0.9.1 configuration files, modified to mirror those in the manufacturer's 1.1.1 firmware

• Configuration.h - configured for EasyThreeD K7
• Configuration_adv.h - configured for EasyThreeD K7
• src\pins\stm32f1\pins_MKS_ROBIN_LITE.h - Added pin definitions for EXP1 port reassigned from LCD to Buttons
• src\MarlinCore.cpp - Includes additional functions to handle complex button behaviour
• src\feature\easythreed_ui.cpp - Button behavour main code
• src\feature\easythreed_ui.h - C header file

Compiled binary - https://github.com/schmttc/EasyThreeD-K7-STM32/blob/master/mksLite.bin

• Hotbed is enabled. If you do not have a hotbed, make sure the temp is set to 0 in your slicer
• Backlash correction is enabled, with all settings on 0 by default

• Make sure 'VALIDATE_HOMING_ENDSTOPS' is disabled, as we do not have X and Y stoppers to provide feedback, and the printer will halt.
• Multiple calls in quick succession to queue.inject_P() will fail. Use a single call, with multiple commands seprated by "\n"

https://github.com/schmttc/EasyThreeD-K7-STM32/blob/Original-Firmware-Marlin-1.1.1/mksRobinLite_nano/Inc/main.h EXP1 (LCD Expansion Port) pins defined for use by physical buttons. Search for line "//EXP1 FOR NANO" at bottom of file.

https://github.com/schmttc/EasyThreeD-K7-STM32/blob/Original-Firmware-Marlin-1.1.1/mksRobinLite_nano/Src/nano.cpp Contains the custom MKS code defining button behaviour. Some of the macros used here are an older style, and no longer compatible with Marlin 2.

Marlin Firmware: https://github.com/MarlinFirmware/Marlin

Marlin is published under the GPL license because we believe in open development. The GPL comes with both rights and obligations. Whether you use Marlin firmware as the driver for your open or closed-source product, you must keep Marlin open, and you must provide your compatible Marlin source code to end users upon request. The most straightforward way to comply with the Marlin license is to make a fork of Marlin on Github, perform your modifications, and direct users to your modified fork.

While we can't prevent the use of this code in products (3D printers, CNC, etc.) that are closed source or crippled by a patent, we would prefer that you choose another firmware or, better yet, make your own.