Multiple Displays

Two displays!

Adding a second display is very easy. First, we do suggest testing both seperately as above. Once you know they work, connect the upper right header of the first panel to the upper left of the second. You can use a long or shorty IDC cable, we happen to like the short ones but the long ones will work fine (they're a little more bulky of course).

Then connect another wire (brown this time) to CS1 this is the CS line for the second panel.
Connect CS1 to digital 5 on the Arduino.

Open up the File→Examples→Adafruit_HT1632→matrixdemo example sketch and change the top part so that you have two panels active, like this:

Download: file
// use this line for single matrix
//Adafruit_HT1632LEDMatrix matrix = Adafruit_HT1632LEDMatrix(DATA, WR, CS);
// use this line for two matrices!
Adafruit_HT1632LEDMatrix matrix = Adafruit_HT1632LEDMatrix(DATA, WR, CS, CS2);
Now upload the matrixdemo test to see the panels light up in order.

3-10 displays

You can chain up to 8 displays, but the system for wiring is a little bit different. Instead of using one cable, you'll need two between each panel. That is so each of the CSn pins can be addressed - the second 10-pin cable has 8 CS pins.

To perform the chain, first you will need to remove the J5 jumper using wick and a soldering iron. This will let you use the second IDC CS pins.

Then chain panels so that two cables go between each set, we suggest shorty cables.
Finally, you will need to use both IDC cables. The first (top left) cable has VCC and GND, as well as DATA and WRITE as in the previous tests.
Then on the second IDC (bottom left) you can connect CS0 (white), CS1 (brown), and CS2 (green). We connected CS2 to digital 6.
Then of course change the object creation to match that you have three CS pins.
Download: file
// use this line for three matrices!
Adafruit_HT1632LEDMatrix matrix = Adafruit_HT1632LEDMatrix(DATA, WR, CS, CS2, CS3);

You can do the same for 4 panels by adding another CS pin.

How many cables do I need?

Depending on how many you want to chain, the number of cables will vary. For 3 or more panels, you will need extras. For more than 2 panels, we suggest using the short IDC cables to keep the wiring neat and avoid having too much power lost to the cable length.

  1. One 10-pin IDC cable (included)
  2. Two 10-pin IDC cables (included)
  3. Six IDC cables - two long ones are included so you need four more short ones
  4. Eight IDC cables - two long ones are included so you need six more short ones
  5. Ten IDC cables - two long ones are included so you need eight more short ones
  6. Twelve IDC cables - two long ones are included so you need ten more short ones
  7. Fourteen IDC cables - two long ones are included so you need twelve more short ones
  8. Sixteen IDC cables - two long ones are included so you need fourteen more short ones
This guide was first published on Jul 31, 2013. It was last updated on Jul 31, 2013. This page (Multiple Displays) was last updated on Jun 18, 2019.