rene / wstation

Weather Station Device with ESP32

WStation is a project that was born from my quarantine. I use to have one of those cheap Chinese thermometers. Unfortunately, it fell down to the floor, ending up with a broken LCD and a useless 433.92MHz sensor (since I didn't have any other device capable of decoding the signals). As you can imagine, perfect setup for a ESP32 project!

Original Device (Chinese Digoo thermometer)

Since I had some free time due to the covid's quarantine, I've decided to start this project completely from scratch and release everything under BSD-3-Clause and CC licenses. Even the original mockup for the GUI can be found here.

WStation device

The prototype was made with a ESP32 DEVKIT V1 compatible device using the case of the broken Digoo thermometer (for sure there is room for visual improvements, specially on the hot glue the I've used to fill the holes on the borders, but in general the final result is not that bad). The radio receiver module have fit inside the case. ESP32 and DHT modules were assembled outside, on the back.

ESP32 and DHT modules assembled on the back of the case

WStation has the following features:

• WiFi connectivity
• NTP Client
• Timezone and Daylight Saving Time support
• Shows Indoor Temperature/Humidity
• Shows Outdoor (from external sensors) Temperature/Humidity (supports up to 3 sensors)
• Shows weekly forecast (next 3 days)
• Support to OpenWeather API
• Support to DHT modules
• Support to HTU2x sensors
• Support to DS1307 RTC modules (optional)
• Support to 433.92MHz NC-7345 compatible sensors (optional)
• Web interface for device configuration (with user authentication)
• Reset setting to factory from button "press and hold"
• OTA firmware update (from Web interface)
• LCD brightness level control

Hardware

WStation circuit diagram

The whole circuit can be built using a few modules:

Module	Description
EPS32 module	ESP32 DEVKIT V1 compatible device
240x320, 2.2" TFT LCD	SPI TFT LCD Serial Port Module Display ILI9341 5v/3.3v compatible screen
DHT module	DHT Sensor to measure Temperature and Humidity
DS1307 RTC module	Real Time Clock module (optional, date/time can be synchronized through NTP client)
433.92MHz RF Receiver module	433.92MHz RF Receiver (with ASK/OOK modulation support)

DHT module can also be replaced by a high precision HTU2x Temperature/Humidity sensor module (connected through I2C):

Pinout connection

Function	Pin number
TFT module DC pin	16
TFT module CS pin	17
TFT module LED pin	27
TFT module SCK pin	18
TFT module MISO pin	19
TFT module MOSI pin	23
TFT module RST pin	5
DHT Data pin	32
Radio sensor	4
RTC SDA pin	21
RTC SCL pin	22
HTU2x SDA pin	21
HTU2x SCL pin	22

Firmware

Setup the environment

To build the firmware, first make sure you have the Arduino/ESP32 environment installed as described at: https://github.com/esp8266/Arduino and https://github.com/espressif/arduino-esp32. The firmware is built using make with the nice makeEspArduino makefile.

First, clone WStation repository:

git clone http://github.com/rene/wstation
cd wstation

Build and flash the file system:

$ cd src
$ make flash_fs

Build and flash the firmware:

$ make
$ make flash

Some environment variables can be customized according to user's setup:

Variable	Description
UPLOAD_PORT	ESP module serial device, e.g. /dev/ttyUSB0
UPLOAD_SPEED	Serial baud rate, e.g. 921600
DEBUG_LEVEL	Verbose level for debug messages
RTC_DS1307	Set to true if a RTC DS1307 module is installed
DHT_SENSOR	Set to true if a DHT module is installed
HTU2X_SENSOR	Set to true if a HTU2x modle is installed
ESP_LIBS	Path to Arduino/ESP libraries (if non default path is used)
ESP_ROOT	Root folder of Arduino/ESP environment (if non default path is used)

Once the device is flashed, future updates can be done through Web Interface. Just select and upload the main.bin file under build folder.

Device setup

Getting a OpenWeather API Key

WStation uses the OpenWeather API to fetch updated weather forecasts. In order to use the API, you should subscribe to OpenWeather (free plan allows 60 requests per minute, which is completely fine for one WStation device) and get an API key. To get the key, please, follow the Instructions at OpenWeather website. After subscribe, you can generate and/or see your keys at the user's area:

You will need to configure your API Key and city name (in OpenWeather's format, e.g. Berlin,DE) on WStation to start to get weather forecasts.

Powering on the device

When you power on your WStation device for the first time, the device will act as an Access Point, creating the WiFi Network WStation. Connect to this network using the parameters shown on the screen:

Setting	Default value
WiFi SSID	WStation
WiFi Password	wstation1234
Username	admin
Password	admin

Access device web interface to configure your API Key, City, WiFi network, etc. When the setup is done, click on the button Save configuration. That's it! Your WStation device is ready to work!

Resseting to factory settings

Any WStation device can be redefined to factory settings by pressing and holding the BOOT button for 6 seconds or through the web interface.

Screenshots of WStation interface

Bug reports

Please, report them on the project's GitHub page