RP2350A Pi-Day Pendant

Happy Pi Day! This project documents a Pi-Day Bling designed around the RP2350A microcontroller, which can change its behavior when it detects a keyword such as Pi, 3.14, or Irrational. The pendant dimensions are 80mm. x 79.5mm.

The pendant's components are highlighted with red rectangle in the image below:

• RP2350A microcontroller - Processor that powers the bling
• ESP32-C3-MiniWi-Fi module - Used to provide wireless capabilities. It runs the AT command firmware that can be controlled via SPI/UART.
• LSM6DS3TR-C IMU - Used to create cool LED effects based on orientation of the pendant
• PiezoBuzzer - Used to generate audio alerts
• Qwiic Sensor Port - To add external sensors via the I2C interface.
• NPM1300 PMIC - Used for charging the Li-Po Battery and serve as a battery fuel gauge
• 512MB NAND Flash - For Datalogging purposes
• Knowles IA611 Microphone - Used for Keyword Detection using on-chip processor
• USB-CPort - Used for programming the RP2350A microcontroller
• Li-PoBatteryPort
• SWDDebugging Port
• 10 x Reverse Mount Neopixel LEDs

Here is a video of the pendant in action!

Demo

In 2023, I built a similar pendant which changes color every time a keyword is detected.