# ABC Soundboards with NeoTrellis

## Overview

https://youtu.be/VhtGKlxV0HI

This guide provides two soundboards based on the Adafruit NeoTrellis M4. they each speak phrases for each letter of the english alphabet from A to Z.

The first soundboard is animal themed and based on the book [**The ABC book** by C. B. Falls](https://archive.org/details/abcbook00fall), published in 1923 and out of copyright. It is available in the Internet Archive.

The second is robot themed based on the book, [**Ladyada's E is for electronics**](https://www.adafruit.com/product/1000), is published by Adafruit which is under a [Attribution-ShareAlike 3.0 Unported](https://creativecommons.org/licenses/by-sa/3.0/deed.en_US) license.

Both books can be downloaded for free in PDF form and they have black and white drawings suitable for coloring!

https://youtu.be/pne3Jat8EHE

## Parts

This project requires the Adafruit NeoTrellis M4 package. You will need a known, good USB A to micro-B cable to load software.

Other parts depend on if you'd like your project portable or not. You can select headphones or speakers. If you want portability, a cell phone recharge battery is ideal, otherwise you'll need 5V power for the speaker and for the NeoTrellis.

You can buy a pre-printed **E is for Electronics coloring book** or download a PDF later in this guide.

### Adafruit NeoTrellis M4 with Enclosure and Buttons Kit Pack

[Adafruit NeoTrellis M4 with Enclosure and Buttons Kit Pack](https://www.adafruit.com/product/4020)
So you've got a cool/witty name for your band, a Soundcloud account, [a 3D-printed Daft Punk helmet](https://learn.adafruit.com/3d-printed-daft-punk-helmet-with-bluetooth)... so what could be missing from your road to stardom? The **NeoTrellis M4 Kit...**

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### USB cable - USB A to Micro-B

[USB cable - USB A to Micro-B](https://www.adafruit.com/product/592)
This here is your standard A to micro-B USB cable, for USB 1.1 or 2.0. Perfect for connecting a PC to your Metro, Feather, Raspberry Pi or other dev-board or microcontroller

Approximately 3 feet / 1 meter long

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![USB cable - USB A to Micro-B - 3 foot long](https://cdn-shop.adafruit.com/640x480/592-01.jpg)

Pick your sound output:

### USB Powered Speakers

[USB Powered Speakers](https://www.adafruit.com/product/1363)
Add some extra boom to your audio project with these powered loudspeakers. We sampled half a dozen different models to find ones with a good frequency response, so you'll get quality audio output for music playback. Simply connect the standard 3.5mm stereo plug into your Raspberry Pi model...

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![Two square-ish USB Powered Speakers](https://cdn-shop.adafruit.com/640x480/1363-07.jpg)

### Cell-phone TRRS Headset - Earbud Headphones w/ Microphone

[Cell-phone TRRS Headset - Earbud Headphones w/ Microphone](https://www.adafruit.com/product/1966)
These earbud headphones are the perfect accessory for your FONA - they've been tested to work with our modules - but can be used with any iOS or Android device that uses a TRRS pinout.  The buds themselves are 16mm in diameter with a nice 40" long.  They come with a...

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![Cell-phone TRRS Headset - Earbud Headphones with Microphone](https://cdn-shop.adafruit.com/640x480/1966-03.jpg)

Pick Your power, to stay or to go:

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Our all-in-one 5V 2.5 Amp + MicroUSB cable power adapter is the perfect choice for powering single-board computers like Raspberry Pi, BeagleBone, or anything else that's power-hungry!

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![MicroUSB power supply with bundled cable and U.S. plugs.](https://cdn-shop.adafruit.com/640x480/1995-02.jpg)

### USB Battery Pack for Raspberry Pi - 10000mAh - 2 x 5V outputs

[USB Battery Pack for Raspberry Pi - 10000mAh - 2 x 5V outputs](https://www.adafruit.com/product/1566)
A large-sized rechargeable battery pack for your [Raspberry Pi](http://www.adafruit.com/raspberrypi) (or [Arduino](http://www.adafruit.com/arduino), or [Propeller](http://www.adafruit.com/category/26), or anything else that uses 5V!). This pack is intended for...

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![Angled shot of white rectangular USB battery pack with 4 dotted lights indicating battery is fully charged. ](https://cdn-shop.adafruit.com/640x480/1566-11.jpg)

# ABC Soundboards with NeoTrellis

## Enclosure Assembly

![](https://cdn-learn.adafruit.com/assets/assets/000/065/541/medium800/adafruit_products_3963-06.jpg?1541982947)

The acrylic enclosure is quick and easy to assemble. Each part is horizontally symmetrical, so there is very little worry about placing them in a "wrong" direction.

## Prep

First, you have the satisfying task of peeling off the protective paper from the acrylic pieces. If you peel off all of the paper without tearing them you will have seven weeks of good luck. Do not squander them.

![](https://cdn-learn.adafruit.com/assets/assets/000/065/543/medium800/adafruit_products_IMG_2336_2k.jpg?1541983108)

![](https://cdn-learn.adafruit.com/assets/assets/000/065/546/medium800/adafruit_products_IMG_2342_2k.jpg?1541983171)

## Elastomer Pads

Place both of the button pads into the top piece as shown. Note, there are two pairs of rubber registration nubs which must align with their associated holes on the Trellis M4 board, so match the orientation as seen in the photos.

![](https://cdn-learn.adafruit.com/assets/assets/000/065/552/medium800/adafruit_products_IMG_2343_2k.jpg?1541983311)

## Place the Trellis M4

Place the Trellis M4 board down onto the elastomer pads with the NeoPixels and button contacts aligned with the buttons as shown. Make sure all of the sixteen registration nubs fit into their associated holes on the PCB.

![](https://cdn-learn.adafruit.com/assets/assets/000/065/561/medium800/adafruit_products_IMG_2346_2k.jpg?1541984539)

![](https://cdn-learn.adafruit.com/assets/assets/000/065/569/medium800/adafruit_products_IMG_2347_2k.jpg?1541984554)

## Frame Layer

Now, place the frame layer which helps hold the board in place.

## Penultimate Layer

This next layer has some large cutouts in it to allow for parts clearance.

## Back Layer

It's the final layer! Lay it down and get ready for some fastening action.

![](https://cdn-learn.adafruit.com/assets/assets/000/065/581/medium800/adafruit_products_IMG_2357_2k.jpg?1541984797)

## Fasteners

Place the five nylon M3 screws through their holes from the front of the case toward the back, then thread the nuts onto them and finger tighten.

![](https://cdn-learn.adafruit.com/assets/assets/000/065/596/medium800/adafruit_products_IMG_2358_2k.jpg?1541984856)

![](https://cdn-learn.adafruit.com/assets/assets/000/065/613/medium800/adafruit_products_IMG_2363_2k.jpg?1541984980)

Your Trellis M4 is ready for use!

![](https://cdn-learn.adafruit.com/assets/assets/000/065/631/medium800/adafruit_products_IMG_2368_2k.jpg?1541985245)

## Customization

Are you the sort of tinkerer who feels the urge to customize things? We knew it! In case you want to try your hand at building a custom enclosure for your Trellis M4, and make all your other DJ/Producer friends jealous, [here are the CAD files to get you started](https://github.com/adafruit/Adafruit-NeoTrellis-M4-PCB-and-Enclosure). Use them on a laser cutter to created a unique wooden faceplate. Or, print the top piece out with ill graphics on a color printer, trim the button holes and screw holes, and make a cool skin. You might even want to use the templates as a reference for 3D modelling a case!

It's easy to press the Trellis M4's reset button through the case using a small object such as a headphone plug, chopstick, or 5mm LED. But, if you're doing a lot of development in Arduino and resetting a lot, you may want to make a button extender. Here's a file you can 3D print for that!

[resetbuttonTrellisM4.stl.zip](https://cdn-learn.adafruit.com/assets/assets/000/067/748/original/resetbuttonTrellisM4.stl.zip?1545149910)
# ABC Soundboards with NeoTrellis

## Setting up CircuitPython and Troubleshooting

![](https://cdn-learn.adafruit.com/assets/assets/000/067/388/medium800/gaming_blinka-Music.jpg?1544470484)

After assembly, plug your NeoTrellis into a computer (mac/PC/Linux) and look for a new flash drive in the operating system file explorer/finder program. It should be named **CIRCUITPY**. If you browse the files on this new drive, you'll see a file named **boot\_out.txt**. If you see this, then you should be set. If not, go to troubleshooting below.

## CircuitPython

The NeoTrellis M4 Express will be programmed using CircuitPython, the easy to use language on Adafruit's Express products. Are you new to using CircuitPython? No worries, [there is a full getting started guide here](https://learn.adafruit.com/welcome-to-circuitpython), although you can start without editing any code.

The code is in text files so you can easily make changes with your favorite text editor. Adafruit suggests using the Mu editor to edit your code and have an interactive REPL in CircuitPython. [You can learn about Mu and its installation in this tutorial](https://learn.adafruit.com/welcome-to-circuitpython/installing-mu-editor).

Info: 

## Libraries

The code uses several libraries for helper code. Please go to the [CircuitPython libraries releases page](https://github.com/adafruit/Adafruit_CircuitPython_Bundle/releases/) and download the zip file for CircuitPython 4.x to your computer hard drive. It will have a name similar to  **adafruit-circuitpython-bundle-4.x-mpy-20181211.zip** but the date will most likely be different (as Adafruit adds more features),

Go into the library zip file and copy the following files to your NeoTrellis **CIRCUITPY** drive into a subdirectory named **/lib** :

- Directory **adafruit\_bus\_device**
- Directory **adafruit\_fancyled**
- **adafruit\_matrixkeypad.mpy**
- **adafruit\_trellism4.mpy**
- **neopixel.mpy**

![](https://cdn-learn.adafruit.com/assets/assets/000/067/475/medium800/gaming_christmas-libs.png?1544647846)

## Troubleshooting

You can use the serial capability in [Mu](https://learn.adafruit.com/welcome-to-circuitpython/installing-mu-editor) or a serial terminal program to connect to the NeoTrellis M4 to interact with the CircuitPython prompt. You can see error messages, restart the program, etc. If you use a terminal program, set it to the COM port that appears when the device is plugged in. In Windows, Device Manager will show a keyboard when NeoTrellis is plugged in. Right click, Properties, Hardware will show the COM port. Connect at 9600 baud.

**Problem: ** I don't see the  **CIRCUITPY**  drive when I plug the NeoTrellis M4 into my computer or I see a drive named  **TRELM4BOOT**  instead.

**Solution: ** Ensure CircuitPython is installed via [this guide](https://learn.adafruit.com/adafruit-neotrellis-m4) **.**

**Problem: ** The code does not run.

**Solution:**  Check the files on the  **CIRCUITPY**  drive.  ** /lib**  should have the latest CircuitPython 4.x libraries and you have placed  **code.py**  in the main (root) directory.

**Problem:**  Not enough disk space for all the files.

**Solution:**  If you have files from another NeoTrellis project, you may have to remove some or all of the other project-specific files to load files specific to this project.  
  
If you use your own phrases, you cannot use long stereo clips or songs for each button, there is not enough flash disk space. You can reduce the number of files below 32. You can trim your clips to make them shorter. You should ensure all your clips are mono instead of stereo. 

**Problem** : My board isn't booting up!

**Solution** : Make sure your  **/lib**  folder is set up with the libraries in the 4.0 latest release and includes adafruit\_trellism4.mpy in its contents.

**Problem:**  I'm not hearing any sounds!

**Solution:**  Ensure you have copied the sound files to the appropriate directories:  **/animal**  holds the 32 animal ABC files and **/electronics** holds the 32 "E is for Electronics" book sound files. The files are in GitHub in a ZIP when you download the code.

Ensure you have headphones or powered speakers plugged into the sound output jack and that the volume is set appropriately. If you have put custom sounds on the NeoTrellis, check that all your files are formatted as Mono 16-bit, 22,050Hz, PCM. 

**Problem:**

> AttributeError: 'WaveFile' object has no attribute 'channel\_count'

**Solution:** You should update the NeoTrellis firmware as described in [https://learn.adafruit.com/adafruit-neotrellis-m4/circuitpython](https://learn.adafruit.com/adafruit-neotrellis-m4/circuitpython).

# ABC Soundboards with NeoTrellis

## Code

Time to download the software and sounds. Click on the **Download Project Zip** button in the top left of the code listing below to get the **code.py** file and two subdirectories: **/animals** and **/electronics**.

Open the ZIP file in your computer File Explorer/Finder. Plug in your NeoTrellis and open the **CIRCUITPY** flash drive that appears when NeoTrellis is plugged in.

Copy **code.py** to the root/main directory.

Copy each directory of sounds, **/animals** and **/electronics** to the root directory so you'll have those two subdirectories. Each of those directories have files named the same, but one set is female voiced (E is for Electronics) and the other one male voiced (Animal ABCs).

Files that have a period in the first character of the filename may be made on Mac computers, no worries.

![](https://cdn-learn.adafruit.com/assets/assets/000/067/452/medium800/gaming_filelist.png?1544645114)

Danger: 

https://github.com/adafruit/Adafruit_Learning_System_Guides/blob/main/ABC_Soundboards_for_NeoTrellis/code.py

If you would like to use the "E is for Electronics" soundboard first with no customization, you can skip to the [Use page](https://learn.adafruit.com/abc-soundboards-with-neotrellis/use).

## The Code and Customization

The code first imports five libraries for use:

```python
import time
import board
import audioio
import audiocore
import adafruit_fancyled.adafruit_fancyled as fancy
import adafruit_trellism4
```

Next is a list of numeric values for the colors displayed on the board. If you think the individual colors need tweaking, you can do it here. If you want the color keys in a different order, you'll change the dictionary `SAMPLES` below the color values. `SAMPLES` contains 32 tuples (groups) which each contain a file name and a color for each button. So Button 1 will play the sound file **A.wav** and display on the NeoTrellis in color `RED`.

### Changing Soundboards

Next is where you would change between from the Animal soundboard and the "E is for Electronics" soundboard. The code: 

```
# Select the folder for the ABC files, only define one,
#   the other line should have a # to comment it out
#SAMPLE_FOLDER = "/animals/"
SAMPLE_FOLDER = "/electronics/"
```

When you load the code above, the soundboard will work as the "E is for Electronics" soundboard and get the phrases in subdirectory **/electronics**.

To change the NeoTrellis to the Animal ABCs soundboard, use Mu or a text editor to make the following changes to that section of the code:

```
# Select the folder for the ABC files, only define one,
#   the other line should have a # to comment it out
SAMPLE_FOLDER = "/animals/"
# SAMPLE_FOLDER = "/electronics/"
```

This change pulls the sound files for the Animals ABC phrase set.

Each directory contains the same file names but they are different phrases. **A.wav** to **Z.wav** play the alphabet phrases. The last 6 keys play different phrases. The code will also play phrase 28 on startup.

If a key is pressed, it will play the corresponding sound file as defined in the `SAMPLES` dictionary. Press a key before the phrase finishes and the phrase will stop and play the new phrase so keys can interrupt other keys.

# ABC Soundboards with NeoTrellis

## Use

The two soundboards that are available for this project:

- **E is for Electronics** - narrated in a US female voice
- **Animal ABCs** - narrated in a US male voice

The code is set for "E is for Electronics" but a small change noted on the previous page will switch the board to the Animals ABC soundboard.

We suggest providing the soundboard and the book together so someone may follow the pages with the corresponding sounds. A set of crayons or pencils may be used to color the book while using the soundboard.

## E is for Electronics
![](https://cdn-learn.adafruit.com/assets/assets/000/066/845/medium800/neotrellis_e-for-electronics-book.png?1543617717)

You can [buy this coloring book from Adafruit here](https://www.adafruit.com/product/1000) or download a PDF copy [here](http://adafruit-coloringbook.s3.amazonaws.com/coloringbook_9-17-2012.pdf). If you'd like to see a Youtube video talking in general about the book, it is [available here](https://www.adafruit.com/product/1000).

This book goes through the alphabet via electronics figures and items. The pictures are in black & white so they may be colored as an activity. For a video demonstration, see below:

https://youtu.be/VhtGKlxV0HI

## Animal ABCs
![](https://cdn-learn.adafruit.com/assets/assets/000/066/864/medium800/neotrellis_Animal_ABCs.png?1543620318)

The second soundboard is Animal ABCs. The board is based on the book The ABC book by C.B. Falls, published in 1923. The book is out of copyright and is [available from the Internet Archive via this page](https://archive.org/details/abcbook00fall) as a [black and white PDF file](https://ia801405.us.archive.org/15/items/abcbook00fall/abcbook00fall_bw.pdf).

https://youtu.be/pne3Jat8EHE

This book goes through the alphabet noting different animals whose name matches the letter of the alphabet. This PDF is also black and white for coloring.

![](https://cdn-learn.adafruit.com/assets/assets/000/066/977/medium800thumb/neotrellis_ezgif.com-gif-maker.jpg?1543872851)

## Activities

We suggest you have a printed copy of one of the books and provide it to one or more people along with the corresponding soundboard. 

Following the book and listening to the sounds makes for a great pairing.

The addition of coloring provides additional activities. Have fun with this project!

# ABC Soundboards with NeoTrellis

## Customization

![](https://cdn-learn.adafruit.com/assets/assets/000/066/860/medium800/neotrellis_mic.jpg?1543619745 Credit: Microsoft Word clip art image)

If you would like a different set of phrases, this is possible with a bit of work.

You have twenty six files labelled A to Z and 6 keys after that numbered 01 to 06 for a total of 32 keys.

## How to Make New Sound Files
The following guide page goes over recording speech files:

[Make It Talk - Generating Voice Sound Clips](https://learn.adafruit.com/make-it-talk/generating-voice-sound-clips)

You can also make sound files for a general soundboard. The Adafruit Learning System has tutorials for [several NeoTrellis M4 Express soundboards](https://learn.adafruit.com/search?q=neotrellis%20soundboard).

The sound files you record or find on the Internet must most likely be converted to a format easier for the NeoTrellis microcontroller to use. The format is WAV files, PCM 16-bit, a maximum of 22,050 Hz and mono (one channel). To convert sound files for use, we suggest following this Adafruit tutorial:

[Microcontroller Compatible Audio File Conversion](https://learn.adafruit.com/microcontroller-compatible-audio-file-conversion)

If you make your own files, you should check to see which subdirectory to use. You can use the existing **/animals** or **/electronics** subdirectories. Or you can make your own subdirectory and change the value of `SAMPLE_FOLDER` in the code to your chosen subdirectory. Be sure there is a forward slash ("/") in front of and at the end of the filename, for example `SAMPLE_FOLDER = "/myfolder/"`.


## Featured Products

### Adafruit NeoTrellis M4 with Enclosure and Buttons Kit Pack

[Adafruit NeoTrellis M4 with Enclosure and Buttons Kit Pack](https://www.adafruit.com/product/4020)
So you've got a cool/witty name for your band, a Soundcloud account, [a 3D-printed Daft Punk helmet](https://learn.adafruit.com/3d-printed-daft-punk-helmet-with-bluetooth)... so what could be missing from your road to stardom? The **NeoTrellis M4 Kit...**

In Stock
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### USB cable - USB A to Micro-B

[USB cable - USB A to Micro-B](https://www.adafruit.com/product/592)
This here is your standard A to micro-B USB cable, for USB 1.1 or 2.0. Perfect for connecting a PC to your Metro, Feather, Raspberry Pi or other dev-board or microcontroller

Approximately 3 feet / 1 meter long

Out of Stock
[Buy Now](https://www.adafruit.com/product/592)
[Related Guides to the Product](https://learn.adafruit.com/products/592/guides)
### USB Powered Speakers

[USB Powered Speakers](https://www.adafruit.com/product/1363)
Add some extra boom to your audio project with these powered loudspeakers. We sampled half a dozen different models to find ones with a good frequency response, so you'll get quality audio output for music playback. Simply connect the standard 3.5mm stereo plug into your Raspberry Pi model...

In Stock
[Buy Now](https://www.adafruit.com/product/1363)
[Related Guides to the Product](https://learn.adafruit.com/products/1363/guides)
### Cell-phone TRRS Headset - Earbud Headphones w/ Microphone

[Cell-phone TRRS Headset - Earbud Headphones w/ Microphone](https://www.adafruit.com/product/1966)
These earbud headphones are the perfect accessory for your FONA - they've been tested to work with our modules - but can be used with any iOS or Android device that uses a TRRS pinout.  The buds themselves are 16mm in diameter with a nice 40" long.  They come with a...

In Stock
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[5V 2.5A Switching Power Supply with 20AWG MicroUSB Cable](https://www.adafruit.com/product/1995)
Our all-in-one 5V 2.5 Amp + MicroUSB cable power adapter is the perfect choice for powering single-board computers like Raspberry Pi, BeagleBone, or anything else that's power-hungry!

This adapter was specifically designed to provide 5.25V, not 5V, but we still call it a 5V USB...

In Stock
[Buy Now](https://www.adafruit.com/product/1995)
[Related Guides to the Product](https://learn.adafruit.com/products/1995/guides)
### USB Battery Pack for Raspberry Pi - 10000mAh - 2 x 5V outputs

[USB Battery Pack for Raspberry Pi - 10000mAh - 2 x 5V outputs](https://www.adafruit.com/product/1566)
A large-sized rechargeable battery pack for your [Raspberry Pi](http://www.adafruit.com/raspberrypi) (or [Arduino](http://www.adafruit.com/arduino), or [Propeller](http://www.adafruit.com/category/26), or anything else that uses 5V!). This pack is intended for...

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## Related Guides

- [NeoTrellis M4 Animated Dice Roller](https://learn.adafruit.com/neotrellis-dice.md)
- [iPad Pro Bumper](https://learn.adafruit.com/ipad-pro-bumper.md)
- [Trellis M4 Audio Filter Visualizer](https://learn.adafruit.com/trellis-m4-audio-visualizer-and-filter.md)
- [Star Trek Soundboard with NeoTrellis](https://learn.adafruit.com/star-trek-sound-board-with-neotrellism4.md)
- [NeoTrellis M4 MIDI File Synthesizer](https://learn.adafruit.com/neotrellism4-midi-file-player-synthesizer.md)
- [Christmas Soundboard with NeoTrellis M4](https://learn.adafruit.com/xmas-sound-board.md)
- [FlappyBird Game for NeoTrellis M4 in CircuitPython](https://learn.adafruit.com/circuitpython-neotrellism4-flappybird.md)
- [Trellis M4 Beat Sequencers](https://learn.adafruit.com/trellis-m4-beat-sequencer.md)
- [Adafruit NeoTrellis M4 Express](https://learn.adafruit.com/adafruit-neotrellis-m4.md)
- [NeoTrellis M4 Noisy Grains of Sand](https://learn.adafruit.com/neotrellism4sand.md)
- [Launch Deck Trellis M4](https://learn.adafruit.com/launch-deck-trellis-m4.md)
- [NeoTrellis M4 Bumper](https://learn.adafruit.com/neotrellis-m4-bumper.md)
- [Trellis M4 Synth Design Tool](https://learn.adafruit.com/synthesizer-design-tool.md)
- [Neotrellis M4 Live Launcher](https://learn.adafruit.com/neotrellis-live-launcher.md)
- [NeoTrellis M4 Arpeggiator Synth](https://learn.adafruit.com/neotrellis-arpeggiator-synth.md)