The firmware of Mks Robin Nano, based on Marlin2.0.x(The based version is based on Marlin2.0 bugfix) and the below by
alpine https://github.com/inib/Marlin/blob/2.0.X-SapphirePro-3.5TFT/

Updated Firmware Binary file This Firmware is specific, for the TwoTrees Sappire Pro. You should ideally compile the binary, for noobs (we are all noobs at some point) I've included the firmware bin file From the Firmware folder Copy to Robin_nano35.bin to a sd card and power on/ reboot your printer, firmware should flash straight away, takes less that a minute to complete *If the process does not start try renaming Robin_nano35.bin to Robin_nano.bin *

https://escope.de/posts/sapphire-pro-marlin/

Settings for the Two tree's Sappire S PRO + BlTouch/3dTouch

See https://github.com/AIIoT/2.0.x-SapphirePro-BLTouch

See https://locxess.de/3d/BLTouch_Anleitung_englisch.pdf to calibrate bltouch/3dtouch

#define min_software_endstops false or use negative value get with with the M851 command.

Ensure Eprom is intialised from Marlin

• M851 ; note the number

• M851 Z0 ; set the offset to zero

• G28 ; home all axis

• G1 Z0; Z axis go to zero position

• The LCD display should show Z = 0

• From the display go to the Menu then Prepare/Move axis/0.1mm/Move Z

• Move the Z axis slowly down until the nozzle is the right distance from the build plate (paper test).*

• Note the Z axis value on the display it should be something like -1.5

• M851 Z-1.5 ; to set the offset you got in the previous step.

• M500 ; Stores the values in EEPROM so that it is not reset when you power the printer off and on.

• If you need to increase or decrease the gap then do:

• M851 Z-1.4 ; Make the gap bigger or

• M851 Z-1.6 ; Make the gap smaller

• M500 ; to save the value to EEPROM

In your slicer's machine setting start script

add after G28; home all xis

G29; probe bed G500; Save to Eprom

It is developed on PlatformIO, we hope more and more developers will participate the development of this repository.

As the firmware is based on Marlin2.0.x which is built on the core of PlatformIO, the buid compiling steps are the same as Marlin2.0.x. You can directly using PlatformIO Shell Commands, or using IDEs contain built-in PlatformIO Core(CLI), for example, VSCode and Atom. VSCode is recommended.

1. Build config:

• default_envs = mks_robin_nano35
• #define MOTHERBOARD BOARD_MKS_ROBIN_NANO
• #define TFT_LVGL_UI_FSMC

2. Update firmware:

• Enter the .pio\build\mks_robin_nano35 directory, copy the assets folder and Robin_nano35.bin to the sd card
• SD card is connected to the motherboard, and you can see the update interface after powering on.

1. Build config:

• default_envs = mks_robin_nano35
• #define MOTHERBOARD BOARD_MKS_ROBIN_NANO_V2
• #define TFT_LVGL_UI_SPI

2. Update firmware:

• Enter the .pio\build\mks_robin_nano35 directory, copy the assets folder and Robin_nano35.bin to the sd card
• SD card is connected to the motherboard, and you can see the update interface after powering on.

Please refer to MKS-Robin-Nano-V2 wiki.

Please refer to MKS Robin Nano github.