Project

nfcAudio is a wifi enabled MP3 player with NFC capability. A tag is placed on top and corresponding file is played.

Software

Each time an RFID tag is detected:

1. It is compared to volume tags
2. If a music is playing with the same tag, stop playing
3. Else GET an URL from embedded NDEF record
4. If there the file contains an URL to an MP3 file, play it.

Libraries

This project depends on

• ESP8266 Audio - Wonderfull MP3 decoder
• Adafruit PN532 - NFC library from Adafruit, which I modified to use interrupts instead of defalut blocking functions. interrupt_spi branch from my repo has to be used until my pull request is merged. (configured by default in platformio.ini file)

Hardware

Tags

Small stickers as well as standard "credit card" size tags can be used. I use a printed picture with thermal laminated film, but you can buy tags that can be printed if you have corresponding printer.
Stickers can also be put underneath objects, toys, 3D printed things... Lot of fun for my 3 years old kid !

Components

• I2S DAC MAX98357A - From Adafruit
• ESP8266 - Wemos mini D1
• NFC Reader PN532

Wiring

I2S DAC - MAX98357A

I2S DAC board	Wemos mini D1 mini pin	ESP8266 pin
LRC	D4	IO2
BLCK	D8	IO15
DIN	RX	IO3
GND	GND	GND
VCC	5V

NFC Reader - PN532

NFC Reader	Wemos mini D1 mini pin	ESP8266 pin
SCK	D5	IO14
MISO	D6	IO12
MOSI	D7	IO13
SS	D1	IO5
VCC	3.3V
GND	GND	GND
IRQ	D2	IO4
RST	NC	NC

Case

Design files are available in onShape, or in the case folder.
The onShape model is fully parametrized, so all variables can be changed to fit you needs.