easy bluetooth controlled scrolling text - led scrolling display

Hi all, in this Instructure I will show you how to create simple scrolling text using led Matrix module.
These modules are both cheap and easy to use.
To make this project more interesting, added Bluetooth feature: you can send messages to the system with your phone!
I will show you how to connect the system with an arduino card, how the program works, and how to connect the device to smart-phone.
If you don't want to use the Bluetooth feature, just check out the last step and see how to use the arduino serial port.
Follow these simple steps to get a nice gadget! !
Any comments for help, tips and ideas are welcome! 10k views ! Many thanks ! !
OK, you need to create this: Again, these modules are cheap and easy to find.
The best thing about these is that you can connect them in series (8 max)
, All the boring hardware aspects are handled by the Library and the max2219 chip.
The problem is that you can't place them directly side by side due to connectors.
You can place it vertically side by side, but the wiring is complicated. (
The wires are under the module. . . )
The solution is to take them from start to finish like the last photo.
When rows and columns are switched, you say "it doesn't work ".
Yes, but don't worry, my program will take care of this and flip pixels every two modules for the perfect rendering!
My suggestion is: use small rubber to keep in touch.
Of course, if you want to do a perfect finish, you can fix them on a piece of wood, or similar wood.
OK, the program is simple: the Bluetooth module is used as a serial client.
The module handles all the boring connection/security aspects.
In fact, the Bluetooth module is connected through two TX/RX signals, acting as a serial port just like a computer.
The Bluetooth client on the phone processes the connection, allowing the user to send and receive text.
OK, the wiring is simple: there is an "input" pin on the left side of the module and a max719 chip on the left.
You can install up to 8 modules in the series.
As far as I'm concerned, I have 5.
Pair the module head to the tail to ensure that the input pin of the first module is at the top (
View pictures).
Connect them in series like pictures.
My suggestion is: wire the module before placing the rubber to avoid wiring errors.
Keep the modules together using small rubber.
OK, the Bluetooth module is also easy to wire: be careful, the module only handles the 3v3 logic level on the TX and RX pins.
Don't connect them on the 5 v pin!
Instead, a level converter is used.
When on, the led on the module should flash.
In fact, when the module starts, the led flashes and the led stays on when the module is connected to the phone.
Great debugging!
My line is ugly. . .
As there is no wire, I have to do something not so good with the breadboard. . . sorry. . . !
OK, this step comes with the program.
To compile the sketch, you need the "Led control" library.
There is information here.
You can download libs here (
There is a button "Download zip" on the right ")
: Remember, you have to decompress them in the "libraries" folder of the main arduino folder.
Make sure the folder name is "LedControl ".
Make sure. H and .
The CPP file is directly inside.
You should see welcome information on the led display. . .
OK, you have to set up a Bluetooth terminal client on your phone.
On the android store you can find them for free.
I will use "Bluetooth SPP" for this project, but any similar application should work.
Just search for "Bluetooth serial" or "Bluetooth terminal" on the app store ".
When running the application again, you can use the Restore last Connection feature to get the connection to the module. Works great !
Of course, the apps you use may be different.
Congratulate you on your success!
This project is great because it is based on a very simple module and the results are very useful.
You might want to use it as a general.
The destination message is displayed. . .
You can do the project by making a shell to hide the wires and make something beautiful. . .
If you don't want to use Bluetooth, just use the program given here.
Using the arduino serial monitor (
Or other terminal programs)
Send a message.
I hope my steps are clear. . .
Ask if you need more explanation! !
Thanks for reading! !