Compiling and Installing

Make sure you use the correct version of the Arduino environment.

For the original Velleman firmware, use Arduino 1.0.6.

For the 1.0.x branch, use Arduino 1.0.6.

For the 1.1.x branch, use Arduino 1.6.9.

Editing the configuration

Each of the Velleman changes can be individually turned off. Open configuration.h and search around line 60:

// Velleman customisations for 3DRAG
#if MB(3DRAG)
  #define VELLEMAN_STRINGS				// Enable the customised Velleman name strings
  #define VELLEMAN_LED_CONTROL			// Enable the RGB LED control code
  #define VELLEMAN_LED_CONTROL_M420		// Enable RGB LED control via M420 GCode
  #define VELLEMAN_STARTUP_SPLASH		// Enable the Velleman boot splash screen
  #define VELLEMAN_ADDITIONAL_MENUS		// Enable additional menus from Velleman (load / unload filament)
  #define VELLEMAN_EXTRUDER_RATE_FIX	// Enable the third party extruder rate fix
#endif

Comment out each line to turn off that feature.

IMPORTANT: If you use the Extruder rate fix, make sure you use the updated Repetier configurations from the RepetierConfigurations folder - or set manually your flow percentage to 100% (90% by default).

Next, make sure you have the correct EXTRUDERS value. configuration.h, around line 75:

// This defines the number of extruders
#define EXTRUDERS 1

For a single head machine, this should be 1. For dual head, 2.

Save your changes.

Installing

Open Marlin.ino in the Arduino environment. Upload the sketch as you would for the official firmware.

Always unplug the printer from mains power before flashing.

Always clear the EEPROM settings after flashing.