Monday, April 20, 2015

First IoT device - Plug

Because was raining outside and I couldn't work in the backyard, I've made rapidly an IoT plug with ESP8266 .

Donor for the case was a timer plug that was in the house. After I've removed its content, I've added my stuff.

IoT plug
Inside the case I have:

  • power supply (220V-3v3 1A)
  • 5V relay ( is working fine on 3.3 V)
  • ESP-01 covered in blue tape 
And the final IoT plug:

IoT final plug

The ESP-01 is accepting JSON over MQTT from my mosquitto broker. 

To control the plug from my phone, I've created an android application that connects over
websockets to mosquitto broker and is sending commands. 

Plug is sending status every 15 seconds to its subscribers and a status after every command its receiving. I can turn on or off  my  lamp with my IoT device. 

For Android application I've used for rapid development a template, but I am planning to build a totally new application that will discover the IoT devices and add them automatically to the control screen.

IoT Plug application
EDIT: The Android application is different now. See this post.

And a video:

Tuesday, April 7, 2015

Post man #4

To extend the range ( which seems to be fine for my project at this time) I've ordered some 
19 cm mini PCI U.FL to RP-SMA WiFi Antenna Cable. My plan was to reuse the antenna from NRF240L01P modules but I didn't checked the connectors. 

SMA U.FL wifi antenna cable and antenna from NRF24L01

Murphy's law is applicable also in this case, so as you can guess they don't match. So the new antennas are on their way also.

I've received also the BMP180 sensors ( replace the old BMP085 version). 
  • Pressure sensing range: 300-1100 hPa (9000m to -500m above sea level)
  • Up to 0.03hPa / 0.25m resolution
  • -40 to +85°C operational range, +-2°C temperature accuracy
  • This board/chip uses I2C 7-bit address 0x77

BMP180 sensor bag

The sensor and its board is very small, which is great. 

So I have temperature and humidity from DHT22, pressure from BMP180, I can now predict the weather for my irrigation platform.