arduino-weather-station

Arduino sketch for regularly logging temperature and humidity data to a private cloud.

Example Output (Serial)

arduino-weather-station v1.0.0 (https://github.com/drasive/arduino-weather-station)
Initialization successful

Reading sensor data
Reading sensor data successful (temperature: 22.30°C, humidity: 49.80%, brightness: 650)
Logging data
Connecting to WLAN "Arduino (2.4 GHz)"
Connecting to WLAN "Arduino (2.4 GHz)" successful (192.168.0.228, -69 dBm)
Writing to Ubidots
Writing to Ubidots successful
Logging data successful

Configuration

The configuration values are found at the top of arduino-weather-station.ino.
A value in angled brackets ([]) indicates an external constant, a slash (-) indicates no value.

Name	Type	Default Value	Description
LED_PIN	uint8_t	[LED_BUILTIN]	Pin of the status LED
DHT_PIN	uint8_t	5	Data pin of the DHT sensor
DHT_TYPE	uint8_t	[DHT22]	Type of the DTH sensor
PHOTORESISTOR_PIN	uint8_t	PIN_A0	Pin of the photoresistor
UPDATE_INTERVAL	uint32_t	5 * 60	Update interval in seconds (not guaranteed to be achieved)
LOG_DATA	bool	false	Log the recorded data to Ubidots
WLAN_SSID	char*	-	WLAN SSID
WLAN_PASSWORD	char*	-	WLAN Password (secret)
UBIDOTS_TOKEN	char*	-	Ubidots token (secret)
UBIDOTS_ID_TEMPERATURE	char*	-	Ubidots temperature source id
UBIDOTS_ID_HUMIDITY	char*	-	Ubidots humidity source id
UBIDOTS_ID_BRIGHTNESS	char*	-	Ubidots brightness source id

Hardware

• 1x Arduino MKR1000 (WiFi101 Firmware v19.4.4)
• 1x DHT22 sensor
• 1x Resistor 10 kR

Optional:

• 1x Photoresistor
• 1x Resistor 10 kR

[Circuit Version (without Photoresistor)](/circuit/Circuit - without Photoresistor.png)

Documentation

Sensor Data

Temperature: -40 to +80 degrees Celsius
Humidity: 0% to 100%
Brightness: 0 to 1023 (higher value means brighter)

Status LED

The following states are communicated using the onboard LED:

• Initializing: LED is on (after turning the device on)
• Initialized: LED blinks three times (after initializing)
• Active: LED is on (reading or logging sensor values)
• Idle: LED is off (waiting for next update)
• Failing: LED blinks (last update failed)

Serial Bus

All actions are communicated through the serial interface. This can be used for wired operation or debugging.

Data Logging (Ubidots)

If turned on (LOG_DATA), the temperature and humidity readings will be send to your Ubidots account.
This requires an active network connection (WLAN_SSID and WLAN_PASSWORD), a Ubidots token (UBIDOTS_TOKEN) and the data source IDs (UBIDOTS_ID_TEMPERATURE and UBIDOTS_ID_HUMIDITY) to be configured.

Data Logging (ThingSpeak)

Logging data to ThingSpeak was removed in commit #147cc09 because it was not reliable.

Failing to read/ log data

If reading any sensor, connecting to the network or logging data fails, it is retried for up to a total of three times.

Photoresistor

If you don't want to use a photoresistor), revert the changes of commit #a100466 or remove the corresponding code.
There is no configuration option to disable reading or logging only the brightness value.

Libraries

• SPI v1.0.0 by Arduino
• WiFi101 v0.12.0 by Arduino
• DHT v1.3.0 by Adafruit (external)
• UbidotsArduino #2803d20 by Ubidots (external)

Feature Ideas

1. Support LCD panel: Planned by the end of January 2016
2. Support barometer: Planned by the end of February 2016
3. Exclude sensitive data from repository: Not worth the effort
4. Keep hisotry of most recent sensor readings: Not worth the effort as long as network connecting works reliably
5. Use better library for uploading to Ubidots: Not worth the effort as long as UbidotsArduino works reliably
6. Add command/ button to force update: Not worth the complexity and effort

License

MIT