Scrolling Text on SMD Matrix with Blynk?

Hi everyone!

I’ve been using blynk for a few months, and am interested in controlling a new type of light: a SMD Matrix, like this

I am using a Particle Boron as my board.

Is something like this possible with Blynk? In other softwares I’ve used, I would specify the # of pixels per row and pixel order, and it would map things… But am not sure if there is some equivalent way to do here? If not, how would I do it?

I have see Blynk tutorials for very small matrixes, but am interested in using this one, which as 2048 leds. Any advice is appreciated!

I’m guessing that you’re envisioning a system that allowed you to use the Blynk interface as a way of Turing the device on/off, maybe inputting text to be displayed, changing options like colour, speed, effects etc?

If so then you’re still going to be doing all of the hard work in your sketch, and adding additional code to capture and use the data that comes from the Blynk user interface.

If you have any code examples that allow these displays to work with hard-coded parameters for text, colour, speed, direction etc then these could form the basis of your Blynk code.
The usual caveats about keeping your void loop clean and avoiding blocking operations in your sketch apply of course.


Thanks for your reply Peter!

100% correct for the goals of the control.

And ok, so I think you’re saying there is no built-in way to setup a matrix using Blynk, and I’d have to manually code it’s parameters… including layout.

If there is any recommended framework/libraries/tools to help with this matrix setup in Blynk, I’d love to know…

No, Blynk simply gives you widgets to allow values, text, RGB colours etc to be inputted via it’s user interface.
Once they are passed over top your device you might use those numbers for anything - setting the target temperature for a heating system, controlling the colour settings for a light or LED strip, turning a relay on/off etc. Blynk has no knowledge or understanding of what these numbers mean to you, its simply a method of passing values from the UI to your device.

The Blynk widgets that are available to you will depend on the type of subscription you have. If it’s a free subscription then widgets like text input and dropdown menu (which you might want to use to select presets) wont be available to you.


Ok thanks Pete!

I’m on the paid plan with these widgets… I just didn’t see how I’d tell Text input to map to my specific LED Matrix’s layout…

I understand now that there is no GUI for this within blynk, and I need to either 1) setup the layout manually in my sketch, or 2) find some software that can do it for me… and then pass values to Blynk to relay to send to my device.

I know nothing about these matrix boards, but presumably there is some sort of library available which allows you to send them text from your device (let’s say that’s a NodeMCU for now).

The library will have example sketches, maybe including one that scrolls some hard-coded text, runs through some different scrolling examples, changes colours, speeds, font sizes etc etc.

This type of thing is fairly typical for libraries for various LCD, TFT and OLED display libraries for devices.

Your task will be to modify these example sketches so that instead of the text, colours, scrolling speed, scrolling direction, font size etc being hard-coded in your sketch, the values that are used will be inputted via the Blynk app.

Your NodeMCU will be connected to the Blynk server as well as controlling the display, and you will use virtual datastreams and the appropriate widgets attached to these in the app. When you update a widget in the app it will trigger the BLYNK_WRITE(vPin) function for that datastream, and you’ll retrieve the value that was inputted via the app and use it to change the corresponding parameter in the code that controls the display panel.

Your first task is to find a C++ library for these display panels, and run the example sketches to ensure that it works as expected,
Then you need to work-out how the various parameters that you wnat to control are changed within these examples so that you can display your own hard-coded text etc.
When you have this working and you understand how the library works the you can look at adding Blynk into the equation, so that instead of these parameters being hard-coded into the sketch they come from the Blynk app.


Yes, all clear… Thank you again for the help, Pete!

I’ll dive into the example sketches for the appropriate example library next.