Hands-on with ThunderBoard React

Exploring the capabilities of the IoT sensor board from Silicon Labs.

The Thunderboard React Kit (122-3409) is a demonstration and evaluation board that features an array of sensors with BLE connectivity for the Internet of Things.

The ThunderBoard React hardware platform contains the following features:

• Silicon Labs Blue Gecko BGM111 Bluetooth® Smart Module
  • 32-bit ARM® Cortex-M4 CPU
  • 256 KB Flash
  • 32 KB RAM
  • TX power: up to +8 dBm
  • RX sensitivity down to –93 dBm
• Silicon Labs Si7021 relative humidity and temperature sensor
  • Temperature sensor accuracy: ±0.4 °C
  • Humidity sensor accuracy: ±3% RH
  • I2C interface
• Silicon Labs Si1133 ambient light and UV sensor
  • Ambient light sensor range: 1 to 128 kilo lux
  • UV index sensor range: 1 to 11
  • I2C interface
• Silicon Labs Si7201 omni-polar, hall-effect sensor
  • Operating point: 30 Gauss max
  • Release point: 10 Gauss min
  • Push-pull output
• Invensense MPU-6500 6-axis motion sensor
  • 3-axis accelerometer
  • 3-axis gyroscope
  • I2C interface
• Two momentary buttons (SW-0, SW-1)
• Blue and green LEDs (LED-B, LED-G)
• 10-pin 0.050”, 1.27 mm mini-simplicity debug connector
• PCB footprint for up to 8Mb external flash device
• Break-out pin pads to connect to BGM111 GPIOs
• CR2032 coin cell battery slot

Demo application

The ThunderBoard React connects to a smartphone or tablet via Bluetooth and an app is provided that lets you reader live sensor data. The app is available for iOS or Android devices. The on-board sensors include an accelerometer, an ambient light sensor and a temperature/humidity sensor.

The app should also connect to a Cloud-based multi-client, real-time service, but this has been disabled in recent versions due to security issues. Silicon Labs have promised that it would be re-instated, but there presently isn’t a time frame. I installed the app on my android phone from the Google Playstore and removed the battery cover.

With the app installed I turned the board on by sliding the switch to the Vbat position.

Then flipped it over and pressed the SW-0 button

.. and after a few seconds the board appears listed at the foot of the screen.

Tapping on the listing takes you to a page showing the three buttons and a cogwheel icon.

Tapping the cogwheel takes you to the setup page, where there are options for metric or US measurements, Centigrade or Fahrenheit temperature, as well as the option to switch to the Car mode if you have bought the bundle which includes a model car.

Back on the main screen the buttons let you go to the environment readings, buttons to turn the LEDs on and off, and a graphical display of the orientation of the board using its motions sensors.

I particularly liked the motion sensor display.

When the Cloud streaming is available Data is stored in Firebase, with a web frontend implemented in ReactJS.

The App source code is available on GitHub and Silicon Labs also supply their development tool, Simplicity Studio, free of charge. This allows developers to create wireless applications and provides hardware configuration, network analysis, real-time energy debugging for the ThunderBoard React and other Silicon Lab products.

Final thoughts

The ThunderBoard React provide a neat solution for evaluating the capabilities of the Silicon Labs Bluetooth and sensor devices. The Bluetooth connection was simplicity itself and in my experience that is not always the case connecting Bluetooth stuff to my phone.

The inclusion of the motion sensor, along with the environmental ones and the fact that it can be bought in a kit with a model car, suggest perhaps that Silicon Labs see key applications in transport settings. Depending upon the required wireless range, I can see the board itself also being a good addition to numerous projects with a requirement for environmental monitoring.