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Template:SAV 3D LCD

Crystal Clear action run.png

Release status: working

LCD controller, rotary encoder and 2 configurable push buttons
Creative-Commons 4.0 CC BY-NC-SA
CAD Models
External Link


The SAV 3D LCD is an LCD with rotary encoder with click button and 2 push buttons to control your LCD. It allows the control of a 3D printer running Marlin firmware and a SAV MkI, sanguinololu, printrboard or similar electronics directly without having to have a computer connected.

Standard features are provided by marlin firmware all of which are fully operational: start and stop prints, control print speed while printing and change many calibration settings - saving these to the AVR’s EEPORM so they are persistent if you turn the printer on and off -. The design also counts with an enclosure box that can be mounted on your printer.

This module does not have an SD reader as this feature is provided by the SAV MkI, making the LCD interface more reliable and glitch free.

The LCD module comes with an expansion module to connect directly to the SAV MkI. Not only does it allow you to connect the SAV with the LCD backpack but it also expands the control to an external 5V device such as a servo for auto-bed levelling. The device's 5V supply comes from a dedicated voltage regulator, this will avoid any interference caused by it (servo) with your board's 5V supply rail.

The module connects to the main controller using a 14 wire ribbon cable using a 3M box connector. The LCD has been tested with a 1.5m ribbon cable without glitches. The entire LCD is controlled using 2 wires through a Shift Register (SR) interface, the rotary encoder has filtered outputs and relying on the internal AVR pull-ups.

SAV MkI and companion SAV 3D LCD

The LCD is a derivative of electroFUN’s Shift Register LCD (SR LCD) which uses only 2 wires to control the LCD, however with the right library (New LiquidCrystal library by fmalpartida) is 4 times faster than the stock LCD driver.


Parameter Description
LCD type Hitachi HD44780 alphanumeric, 20x4, Blue background white text
LCD interface 2 wire shift register
Control Quadrature rotary encoder with push button, 24 PPR
Push button 2 (predefined for KILL and HOME)
Connection 3M boxed connector to LCD and expansion module 14 wire ribbon cable
Expansion module 1 IO
5V regulated output 62dB ripple rejection - Typ


Configuration and setup

This setup guide is for Marlin, however most of the steps in this section are also applicable to configure other firmware.

Firmware setup

Download and Install the New LiquidCrystal library

The first thing you will need is to download the New LiquidCrystal library from fmalpartida New LiquidCrystal library

Follow the instructions to install the library:

  • Download the most recent version of the library - download.
  • Install the library in the Arduino SDK library pool. To install the library, simply remove the stock Arduino LiquidCrystal library from the Arduino IDE install and replace it by this one.

To learn about libraries please follow the instructions in [ Library Tutorial], there is a Section in the Tutorial indicating how to install a library.

'REMARK: Don’t worry this library is completely compatible with the Arduino IDE stock library, the main difference is that it supports multiple LCD drivers and about 4 times faster than the stock library.

Marlin firmware download and setup

If you are using the SAV MkI follow Marlin’s installation guide described in its wiki page: SAV MkI Firmware.

You can download Marlin’s SAV MkI firmware configuration from here: SAV MkI Marlin

Once you have Marlin installed in your system and the New LiquidCrystal library, to configure and active that SAV 3D LCD you have to edit the ‘’’configuration.h’’’ and change the following lines:

//[FMC]#define SAV_3DLCD
//#define SAV_3DLCD


//[FMC]#define SAV_3DLCD
#define SAV_3DLCD

Now you can compile and download the firmware on your SAV MkI. Following the instructions in the SAV MkI wiki page:

20131116113208-IMG 6530.jpg

SAV MkI firmware Section

When download completes, replace the jumper and press the reset button of your SAV MkI. If nothing appears on the LCD screen adjust the LCD’s contrast by adjusting the trimmer pot located at the back of the LCD.

REMARK:' The latests boards being shipped already have the firmware support for the LCD enabled. Otherwise, be sure to disable JTAG.


This is a small step by step guide to connect the SAV 3D LCD module to your Sanguinololu, printrboard or teensylu.

Find the backpack module that should accompany the SAV 3D LCD. Make sure that your board is powered off and follow the steps below.

SAV 3D LCD backpack module

Step 1 - Connect the backpack module

Connect the backpack module to your printer electronics (in this case the SAV MkI) observing the orientation in the image below. The backpack should be flush with the board facing inwards.

SAV 3D LCD backpack module connection

Step 2 - Connect the ribbon cable to the backpack

Connect the ribbon cable to the backpack module. The cable can be connected towards the printer electronics or away from it. It will depend if you wish to have the ribbon cable facing downwards or upwards on your LCD module. I recommend that you connect it as the image below so that you can print the LCD's enclosure and mount it on your printer electronics.

SAV 3D LCD backpack ribbon cable connection

Step 3 - Connect the LCD module to the ribbon cable

Connect the ribbon cable to the SAV 3D LCD module. You should end up with the connections as follows:

SAV 3D LCD final assembly

Remember to upgrade your board's firmware as indicated in the Firmware setup section. If everything has gone well you are set and good to go.

That's it, power on and enjoy.

Where to get one

If you'd like one you can find who has them in stock here:

Source files

Quick reference

SAV 3D LCD quick reference schematic

Schematics and CAD files


You can also download an print an enclosure for the SAV 3D LCD. There are two enclosures, one to be used as standalone.

Original enclosure

  • 1 x enclosure
  • 1 x Lid
  • 1 x Support for your printer [optional]
SAV 3D LCD housing

There are a few accessories and couplers that accompany the housing, all of which you can download from here: download

REMARK: Print the housing face down.

Community Edition Designs

Designed by E. from RepRap Revolution.

SAV 3D LCD housing

Download design and accessories from: download


The author would like to thank all the project supporters from the RepRap Clone Wars community:


Proyecto Clone Wars