BLE serial hub to WiFi and Blynk visualisation app

So that I can continuously post environmental data to the Blynk cloud service from my Bluetooth environmental monitor, I’ve implemented a simple design using a Keyes HM-10 Bluetooth 4.0 module and a Wemos D1 mini WiFi device as a Bluetooth hub and internet gateway. If you are not familiar with the Wemos D1 Mini. It’s an esp8266 WiFi device on a convenient carrier board useful for bread boarding but also giving you the ability to use the Arduino development environment.

The Wemos D1 Mini which I purchased also had LUA implemented. This initially made me wonder how I would run Arduino C code instead. But as it turns out you just program it as usual after installing all the Wemos library’s and tools, the Arduino environment simply overwrites whats there.

In this hub project the Wemos talks to the HM-10 at intervals and posts the data onto the Blynk cloud service.

  • Wemos D1 mini
  • HM-10 (original hmsoft) Jinan Huamao technology Bluetooth low energy
  • Mains powered USB supply
  • My previous battery operated Bluetooth LE environment monitor hardware which uses serial transfer
  • Arduino development environment
  • Blynk library and tools for arduino
  • Blynk app in your smart device

The Blynk app works quite well. It’s easy to implement and change settings. You get some credits for basic widgets and pay for more if you want them. Below are some screen shots showing a virtual input setup and the available widgets.

Overall the project worked well, i like the simplicity of the Blynk app. The hardware now needs putting on a PCB and fixing into a suitable housing. Update to come.