ESP32 Soundboard
================
Soundboard (computer program), a web application or computer program with buttons that play short, often humorous sound clips.


## Hardware
* [ESP32] µC
* [MAX98357A] PCM Input Class D Audio Power Amplifiers
* [SD card]


## Wiring

### SD card
ESP32 pin     | SD card pin | Notes
--------------|-------------|------------
GPIO14 (MTMS) | CLK         | 10k pullup
GPIO15 (MTDO) | CMD         | 10k pullup
GPIO2         | D0          | 10k pullup, pull low to go into download mode
GPIO4         | D1          | 10k pullup; not used in 1-line mode
GPIO12 (MTDI) | D2          | otherwise 10k pullup (see note below!); not used in 1-line mode
GPIO13 (MTCK) | D3          | 10k pullup needed at card side, even in 1-line mode
N/C           | CD          |
N/C           | WP          |


## Build
```bash
git clone https://dev.xd0.de/hendrik/soundboard.git
cd soundboard
virtualenv .
source bin/activate
pip install -U platformio
platformio run -t upload && platformio device monitor -b 115200
```

## ToDo
* Prototype
* Keypad layout
* internal DAC?
* Add-ons?


## References

[ESP32 overview]: http://esp32.net
[ESP32]: https://eckstein-shop.de/ESP32-Dev-Board-WiFi-Bluetooth-CP2102-USB-to-Serial-with-LiPo-charger
[MAX98357A]: https://eckstein-shop.de/Adafruit-I2S-3W-Class-D-Amplifier-Breakout-MAX98357A