embedded

Experiments with embedded devices. This repository contains Arduino sketches and accompanying Python scripts.

led-on-input.ino

Usage:

• Connect to serial port at 115200 baud
• Send A to flash blue LED
• Send B to flash green LED
• Send C to flash red LED

ble.ino | bleak.py

Usage:

• Scan for devices to find the device you want to connect to
• Update BLE_DEVICE_ADDRESS variable
• Currently hardcoded to read BLE Characteristics of certain handler numbers at src/bleak.py#L25
• Uses an asyncio.Queue for collecting notifications. This is in preparation to feed data into an ML workflow for training

acc-serial.ino | acc_serial.py

Usage:

• Much simpler sketch for transmitting acc data over serial
• Has more bandwidth for higher sampling rate as well

audio-serial.ino | mic_serial.py

• Transmit 16-bit integer PCM from the Nicla Voice through serial port
• This was particarly tricky to figure out because:
  • Arduino docs suggests that PDM library can be used, which is not the case
  • Audio samples are only accessible through NDP.extractData. Moreover, NDP will only be initialised if all 3 synpkg are successfully loaded
  • This means that your Nicla Voice will always boot with a bunch of shit printed into the Serial port, which you need to kill
• Requires pyserial module

References

• nRF52832
• Nicla Sense ME SENSOR_ID MACRO
• Arduino BLE documentation
• Arduino BLE API
• Arduino BHY2 UML
• Arduino Audio Tools
• Bleak documentation
• BHI260AP Datasheet