RGB Matrix displays are a great way adding interactions to a project and displaying objects in a 2D space. RGB LED matrices can be used as a display for playing games, display animations, watch movies, display sensor data, and much more can be the done with these big and beautiful LED displays. Of course, RGB Matric display is best controlled with a high-speed processor like FPGA, but you can still use the Raspberry Pi to control them also. Most of the things (if not everything) the Raspberry Pi can output to a monitor can be displayed on LED matrices display.
Adafruit has announced the arrival of its RGB Matrix control board for the Raspberry Pi called the Adafruit RGB Matrix Bonnet. The Matrix Bonnet allows one to use the popular Raspberry Pi to control RGB Matrics displays to create a colorful scrolling display, view short videos, and for showing animations. The matrix board plugs easily into the Pi and works on any Raspberry Pi with a 40-pin GPIO header – Zero, Zero W/WH, Model A+, B+, Pi 2 and Pi 3. If you still use the old model 26-pin boards like the Model A or Model B, unfortunately, the bonnet can’t plug into them, and you will need the newer boards.
The Matrix control board can work with any 16 x 32, 32 x 32 or 32 x 64 RGB LED Matrices with HUB75 connections. It is also possible to use the bonnet board with 64 x 64 matrix display by doing some hardware hacking – soldering a small jumper on the PCB. And yes, you can get more displays by chaining multiple matrices together for a bigger display. Chaining numerous displays together will also cause some extra workload on the Raspberry Pi itself.
The bonnet board is quite rugged and comes with an inbuilt power protection circuitry to protect the board from short circuits, over and under-voltages. It has onboard level shifters to convert the RasPi’s 3.3V to 5.0V logic which will create a glitch-free matrix driving for 5V logic RGB Matrix display. It also comes fully assembled and no need for any extra soldering work.
The main advantage of the Adafruit RGB Matrix bonnet is that it will allow you to interact with RGB matrix display while avoiding the complicated wiring involved with connecting those displays.
The RGB Matrix Bonnet for Raspberry Pi is now available to purchase priced at $14.95 and can be bought on the Adafruit online store. The bonnet works with only HUB75 type RGB matrices and not the likes of NeoPixel, DotStar or other ‘addressable’ LEDs. For more information about using the bonnet, check out the product page on Adafruit.
This is my second project for LED Driver based on CAT4101 IC. The first project was for single White LED. This project has been designed to drive 3 channels of RGB LEDs with PWM signal which helps to create multi-color LED light. Arduino Nano is used to generate PWM signals for RGB LEDs and board has 3 tactile switches and Analog signal input to develop various RGB LED related applications. Each channel can drive load up to 1A and input supply up to 12V DC. 1A X 3 Constant current LED driver shield for Arduino Nano has been designed for verity of LED related applications. The shield provides accurate LED current sink to regulate LED current in a string of LEDs. The LED current is mirrored and the current flowing from the RSET is set by PR1. On board 2W X 3 LED are used for testing purposes.
PIXO Pixel uses an ESP32 to control a matrix of 256(16×16) RGB LEDs. It is an IoT device that can display information via Wifi and BLE.
The PIXO Pixel is an open source RGB display that uses the very cool, APA102-2020 Addressable LED in a 16 x 16 array. These LEDs are very fast, bright, and tiny; only 2mm x 2mm! Controlling the LED matrix is an ESP32 which is a WiFi and BLE connected microcontroller than can be programmed using the Arduino IDE(Or MicroPython!). Together these make up a very cool desktop display that you can program to do pretty much anything you want. There is also an added proto board for if you want to add more components like an accelerometer, thermometer, light sensor, potentiometer, anything!
PIXO Pixel – An ESP32 Based IoT RGB Display – [Link]
Chromatron is an open source Wifi pixel controller designed to make LED pixel projects easy and fun.
Hi, I’m Jeremy! I’ve designed a toolkit for making art with LED pixel strips, and I’d like to share it with you! Chromatron takes custom designed hardware and feature-packed firmware, sprinkles it with some Python, and serves up a delicious new platform to help you transform your world into a psychedelic dreamscape.
Martina @ natural-nerd.com build a sound reacting LED light using Arduino:
Hi! In this build we’ll make a good looking light that dances to all sounds and music, using simple components and some basic Arduino programming. It makes an awesome effect while standing on the desk when gaming, playing music, and anything else that makes sound really. Let’s get going!
LucaBellan @ open-electronics.org re-created the Ambilight TV effect on any other TV using Raspberry and Kodi. He writes:
The screen’s edges are divided into logic sectors, and each sector is associated with a specific LED and, by making a color average of the pixels, you can find the color to set to be reproduced by the LEDs; this operation is repeated for all the LEDs mounted on the TV and all of this is repeated hundreds of time per second in order to provide synchronicity and maximum smoothness to the colors projected around the TV.
With RaspiLight we can re-create this technology and apply it to any flat-screen TV, but there’s more: even when the TV is off, we can control the system through an Android or iOS app and create static or dynamic light effects and make the TV an animated lighting point and not just a simple lighting piece of furniture.
RASPILIGHT: an open project for Ambilight TV effect – [Link]
Besides looking damned good on an otherwise bland and ordinary desk, this project is about more than just being attention grabbing eye candy. It’s about demonstrating a small portion of our single board computer capabilities by hooking up a color sensor, RGB light strip, and enclosing it in a nice looking wooden enclosure. We’re dubbing it the “aurora boxealis”, and it’s made to stand out from the crowd at trade shows and provide a fun, interactive way to professionally demonstrate an interesting sensor, in this case a color sensor. Grabbing a color swatch from the table and placing it on the top of the box will trigger the lights to mirror that color.
The Aurora Boxealis – A Color Sensing and Mirroring Project – [Link]
The Design Idea in Figure 1 is a color detector capable of generating an RGB triplet over a high dynamic range, a useful attribute for machine vision applications. The circuit implements auto-exposure control to achieve this. Thus, RGB values for a subject are invariant over a range of light intensity.
Color sensor achieves high dynamic range with auto exposure – [Link]