What is it?

WiFi/BLE-enabled e-paper display for I2C sensors. Arduino compatible software on Platformio. 3D printable case.

Specifications

• MCU: ESP32C3
• Power supply: 2xAA, 3V
• Deep sleep current: 0.038mA
• Screen size: 2.13"
• Display resolution: 212(H) × 104(V) pixels
• Connectivity: I2C, UART over USB, UART
• Extra GPIO: 2
• Sensors: Temperature, Relative humidity
• Temperature accuracy: 0.2°C typical
• Relative humidity accuracy: 1.8% typical

Description

This is a pre-packaged solution for all the cases when you need a low power display for your sensor data with WiFi or BLE connectivity - to exchange data with online services or provide it to mobile apps.

The board comes with e-paper display, industry standard ESP32C3 microcontroller and a top of the line Sensirion SHT40 relative humidity sensor. I2C port with switched power is available for any I2C sensors. UART pins and two spare GPIOs are available for additional hardware expansion.

Firmware is a ready made scaffold, consisting of seamless WiFi connectivity provisioning, onboard sensor reading and optimizations for the lowest power consumption.

The board is easy to program via USB cable using Platformio, code is Arduino compatible.

Both the hardware and firmware are open source. 3D printable case files are available on github page.

MQTT backend infrastructure

• To quickly see your data piping in follow this guide: Getting started with MQTT
• To setup your own backend for data storage and display follow this guide: docker-compose-mosquitto-influxdb-telegraf-grafana