Install RepRap Discount Full Graphic Smart Controller (LCD + SD CARD) for RAMPS 1.4 to any 3D printer
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Many times I get the question how did I connect the “RepRap Discount Full Graphic Smart Controller” display unit to my 3DRAG or Velleman K8200 printer copy. In this short video I will reveal all secrets. Basically besides the display itself you will need a 2×10 IDC connector, some patience and some changes in Marlin software. Coming up!
Well let’s start. First I will reveal my reverse engineering procedure in short. After that I will show you the scheme. If you need pictures for a closer inspection, you can find them on my homepage. All the links are in the description below. If you want to make LCD for your printer just follow connection schematics I will show on-screen. I made a detailed video so you can troubleshoot if you have problems. You will be even capable of adding other LCDs to any other 3D printers. I encourage you to hit the LIKE button, SHARE this video with your friends, SUBSCRIBE to my channel and click notification bell and COMMENT below if you have any questions or better solutions. I also invite you to watch my other videos.
REVERSE ENGINEERING
Firstly I had to compare the RAMPS and 3DRAG schematics. It took me some time and precision and I finally came up with the scheme. The LCD unit uses two 2×5 IDC connectors EXP1 and EXP2 which connect to AUX-3 and AUX-4 on RAMPS via adapter board. Checking the connections I figured out which wire goes to which digital alias output of Arduino microcontroller. After that I translated them to digital ports of standard AVR mega chip. As an example let’s take LCD enable pin. It goes to pin 3 on EXP1 connector, which goes to pin 13 on RAMPS AUX-4, which means it is D29 in Arduino nomenclature. This represents port A pin 7 on mega2560 chip or pin 71 on pinout. And so on for each wire.
SCHEME
For the ease of use here is the scheme. On the first picture there is the EXP1 connector and on the second one the EXP2 connector. I added names of ports. The first number represents the pin number on 3DRAG expansion connector. So the VCC on EXP1 goes to VCC pin 16 on expansion connector on 3DRAG PCB. I marked the bottom right RST pin of 3DRAG connector by number 4. MISO above is marked 3 and so on from right to left. Why do I start with pin 3 you ask? Because pin 1 and pin 2 of the female connector we put onto 3DRAG controller hang in the air and are not connected anywhere. 3DRAG connector is 2×9 and I advise you use 2×10 connector. Why? Safety reasons. A larger connector cannot be put on the wrong way. As you can see on the 3DRAG controller we have a FAN connector next to our connector on the left. If you put some plastic into first and second hole on our cable connector, you will not be able to put it in the wrong way. Just safety I say.
MAKING CONNECTOR
You will have to cut two connectors from the cables which came with your display. Separate the ends of ribbon cable and put them organized according to the scheme. Here are some photos of the cable to ease your work. Regarding the SD card detection wire on EXP2 pin 7, I do not use it. RAMPS has it connected to Arduino D53 alias SS pin. While pin 9 on EXP2 is connected to ground. You can leave it unconnected as we connect the ground on EXP1 connector.
ENCLOSURE
At the end all I had to do was to print the enclosure. I found one which suited my needs on Thingiverse.com. See how it looks like! Thank you for watching.
REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER
MARLIN
Search and find the following entities and do things I advise:
1. uncomment #define SDSUPPORT for SD CARD support
2. uncomment #define SD_CHECK_AND_RETRY
3. set #define ENCODER_PULSES_PER_STEP 4
4. set #define ENCODER_STEPS_PER_MENU_ITEM 2
5. choose if you need #define SPEAKER
6. uncomment #define REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER and comment all other LCDs
This is all.
ABOUT
How to install a cheap RepRapDiscount Full Graphic Smart Controller for RAMPS 1.4 to any 3D printer. In this case I use “RepRapDiscount Full Graphic Smart Controller” display and install it to 3DRAG or Velleman K8200 3D printer. Steps: reverse engineering, schematics, how to make a connector, enclosure. Marlin instructions. Simple steps. An intermediate tutorial.
