How to play more than 12 tracks with the Touch Board
Find out how to play more than 12 tracks with the Touch Board
The 12 electrodes on the Touch Board allow you to play 12 tracks when you touch each electrode. If you want to play more than 12 tracks, then there are two methods to consider: The first is playing random tracks from a folder for each electrode, and the second method is connecting two or more Touch Boards together. In this tutorial we will explain both methods to you.
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Setting up the Touch Board
Before you get started, you first need set up the Touch Board. You can do this by following the Touch Board set-up tutorial.
There are two methods to explore. For the first method, we are going to use the “Random_Touch_MP3.ino” sketch. First, open the sketch in File->Sketchbook->Touch Board Examples in the Arduino IDE and upload it to your Touch Board. When you have uploaded the code, turn the board off and insert its SD card into your computer.
Prepare the SD card
With this sketch, we play random files from a folder when pressing an electrode. Contrary to the Touch_MP3 sketch, you don’t have to give your tracks specific names. Instead you have to create 12 folders, labeled “E0”, “E1”, “E2” and so on, up to “E11”. Each folder is accessed when the respective electrodes is touched. In each of these folders you can add as many tracks as you want, on the right are some examples.
Insert SD card and touch the electrodes
After you have ejected the SD card, insert it into the board, connect the board to speakers and turn the board back on. If you now touch the electrodes, it will play a random track from the respective folder!
Connect two or more Touch Boards together
Another method to play more than 12 tracks with the Touch Board is by connecting another Touch Board to the first one. There are two codes to upload. For the main board, select “primary_mp3_board” from File->Sketchbook->Touch Board Examples -> multi_touch_board_mp3 and hit upload. For the second board, select “secondary_mp3_board” from the same folder location.
When you have uploaded the codes you need to connect the boards together, but make sure to turn the boards off first. You can find the wiring diagram in our GitHub repo. Later, you will only need to power the first board, the second board receives power via the 5V pin.
Prepare the SD card
Insert the SD card from the primary Touch Board into your computer. For this method all the tracks are saved on the primary board’s SD card. When you connect two boards together, you can play up to 24 tracks. All of these need to be on one SD card, named from TRACK000.mp3 to TRACK023.mp3.
Touch the electrodes
After you have ejected the SD card, put it back into the primary Touch Board. If you now power the first board, you are able to play the first 12 tracks from the primary Touch Board and the second 12 tracks from the second Touch Board. You can extend this method to connect up to 7 Touch Boards together. You can also use a similar code for the MIDI function, have a look at the Sketchbook folder or at the GitHub repo!