Introduction: BT LED Matrix Display - 80x8 Px Arduino Based
In this guide I will show you how to make your own Arduino LED Matrix display! In this project I decided to make my own PCB that is based on Arduino UNO microcontroller - Atmega328p. Bellow you will find the electronic schematic with PCB layout so you can easily produce it.
Display Features:
- Time
- Day of the week
- Date
- Temperature and Humidity
- Ticker (scrolling) Text
- Adjustable brightness level
- Bluetooth communication
- Memory saving
The board is specially design for up to 10 led matrix displays with MAX7219 IC. You can display the time and date (DS1307 RTC IC), temperature and humidity (DHT-22), change the brightness (15 levels or auto via photocell) and scroll a text message. We have developed an android and windows application to update time/date, brightness and text message via Bluetooth connectivity. The text and brightness value are stored in EEPROM memory, that means that every time that you will turn off/on the unit, these variables will be loaded from memory.
Assembly Video:
We are supporting the open hardware - software community so this project will be marked as an open-source. Before share/copy/change anything of below guide, make sure to read and agree with the CC BY-NC-SA licence agreement! Many thanks to the developers of all Arduino Libraries!
Step 1: What You Will Need - Hardware
For this project you will need:
- 1x Atmega328 (with Arduino UNO bootloader)
- 1x 28 DIP socket
- 1x 16 MHz Crystal Oscillator
- 1x 10 uF capacitor
- 2x 22 pF capacitors
- 2x 10 kOhm resistor
- 1x 100nF capacitor
- 1x Photo-resistor
- 1x Buzzer
- 10x LED Matrix 8x8 MAX7219 modules
- 1x DHT-22 Temp/Hum Sensor
- 1x HC-06 or HC-05 Bluetooth module
- 1x DS1307 IC
- 1x 32.768 kHz Crystal Oscillator
- 1x 8 DIP socket
- 3x jumper10x male pin header
- 1x 5pin female header
- 1x Battery holder CR2032
- 1x Coin battery CR20321x Power supply 5v 3A
- 1x 2pin screw terminal (p5)
Step 2: Circuit Schematic - PCB
Order it from pcbway.com and get 10pcs PCB for free! (only for new members). Instructions on how to order it can be found in the video.
Tip: You can also make your changes to the circuit - online - here.
Step 3: The Code
Tip: Use a usb to ttl module to program your pcb (or the Arduino uno board)
Attachments
Step 4: Assembly and Box
Assembly the pcb, you will need a soldering iron, it will take some time...
For box use black - transparent plexiglass, 3mm thickness:
- 2pcs 33x4 cm
- 2pcs 33x6 cm
- 2pcs 6.6x4.6 cm (left and right)
Optional, if you have a 3d printer you can print the left and right side.
Step 5: Software and Configuration Protocol
From here you can download the software for windows os.
https://www.ardumotive.com/uploads/1/2/7/2/1272651...
For Android app, download it from Android PlayStore
-Update time and date with your device clock
-Update brightness level
-16 available levels (set to 0 for automatic adjustment)
-Change the ticker (scrolling) text (set to blank to deactivate it)
How to use it:
Turn on Bluetooth and pair your display. The default name of the Bluetooth module is "HC-06" or "HC-05" and usually the password is "1234".
Now open the application, press the "Load Paired Devices" button and select your BT module.
Note: If you can't establish a connection with your LED Matrix Display, just restart it.
If you have any problem with this application just send me an email.

Participated in the
Make it Glow Contest
11 Comments
1 year ago
Din and clk pins are different in code and circuit diagram.everyting is ok in my circuit according to defined .but nothing works all leds glows steady .is this project working or fake ...have anyone made it working please reply and help me out at(panesargurpreet99@gmail.com)
1 year ago
Please give link of Bluetooth application
2 years ago
You have posted such a beutiful project here but I can not find the bluetooth app associated with it.
Can I use a different app for this project?
Question 2 years ago on Step 5
How do I download the APP. I tried to download through the APP Play Store but I have no success. I HAVE A HUAWEI Y7. On the other hand, in the dispaly time I get 165: 165: 85 and date 165: 165: 2165, why is that?
I congratulate you on your very interesting project.
3 years ago
1) Can FC16 Matrix Modules (from eBay) be used?
If so, what should be changed in the sketch?
2) Can DS3231 be used instead of DS1307?
Thanks
Reply 3 years ago
1) If the FC16 Module uses the MAX7219, yes you can use it without any changes
2) As the DS3231 IC has a different pinout from the DS1307 IC, no you cant use it... it's in compatible with this pcb board.
Reply 3 years ago
Thanks for the reply
1) Yes, the FC16 uses the MAX7219. So, I mean the orientation of the pins.
2) I said about the DS3231 because it is much more accurate than the DS1307 and, in this case, periodically (of course, for a long time), you must define the time in the sketch.
Reply 3 years ago
You will not have a problem, just connect the cables as the pinout label. About the setting of the time, you can use the software app for android or windows and update the clock via bluetooth. This is necessary in first time and when you will change the coin battery after some time. I will take a look of the DS3231 in my next project. Thanks
Reply 3 years ago
I don't want to be bothering you, but if you adapt the PCB to the DS3231, it may be easier for you to design for the complete Module and not just for the CI as you did for the DS1307. Thanks
Reply 3 years ago
Thanks for the reply; I think it would be a good idea to adapt the DS3231 to this PCB.
I will wait.
3 years ago
If I were you, I would add music controller to it, our at least a functionality to show the curernt music that is playing on the connected device.