esp8266-dth22-ts

Mini DIY low-powered weather sensor, ESP8266-01(ESP-01) connected with DHT22 temperature/humidity sensor, that publish data to ThingSpeak channel.

Requirement

ESP-01 Wifi module (or any compatible ESP8266 module)
DHT22 temperature/humidity sensor (or DHT11)
3.3V Power source
Wires, connectors, etc.
Arduino IDE with
- Board package: "esp8266" by ESP8266 Community https://github.com/esp8266/Arduino
- Library package: "DHT sensor library" by Adafruit (Version 1.2.3) https://github.com/adafruit/DHT-sensor-library/tree/1.2.3
Thingspeak channel

Change Thingspeak API key, Wifi SSID and password.
- Also change the sensor type if you are not using DHT22.
Hardwire ESP XPD_DCDC pin (bottom right corner of the mcu) to RST pin. This is neccessary for ESP-01 to wakeup from deepsleep.
Upload the code to ESP using Arduino IDE.
Connect ESP with DHT22 and power.
- DHT22 data pin to ESP GPIO2.
- DHT22 Vcc pin to ESP GPIO3(RX).
- 3.3V to ESP's Vcc, ESP's CH_PD.
- (recommend) Pull-up ESP's GPIO0,GPIO2,RST pins with 10K resistors.
- (recommend) A 47uF capacitor between 3.3V and GND.
- All GND to ground.

The sensor wakes up, reads and sends data to Thingspeak server, then goes to deepsleep for 5 minutes and repeats.

Powered with 2x AA batteries (average alkaline, 3V.), directly connected without regulator.
It operated for about one week until the battery voltage is dropped below working level of DHT22.