[captain obvious mode on]
You can buy a lot of crap on Aliexpress. Seriously – A LOT. But you can also buy stuff you need for fraction of the price you need to pay in your country (well, I guess if you live in China it’s not the case). And if you are a geek – you are in heaven, cause most of the world electronics comes from there anyway.
[captain obvious mode of]
My wife wanted few temperature and humidity meters, cause the old ones was crap and broke down after two years. They say: “Happy wife happy life”, so I’ve ordered five ESP-12E yellow boards, five DHT-11 modules, one 128×64 OLED screen, UART USB connector, few buttons and bunch of wires.
Not sure if this is what she meant, but hell, this will be fun project :D
It came two days ago, nicely packed. So I’ve played with it a little bit – tried to connect it with my laptop, flash it with micropython, play with sensors, leds and screen. Just wanted to check if everything works as I expected and i didn’t break anything in the process.
The idea (for now) is to create sort of ‘sensor cloud’ that communicates with the central one (with display, buttons and also sensor) which orchestrate the whole thing, displays stuff and also pushes the data online for reading it through our phones (website, or maybe a simple app for android?). I will see how it plays during development, cause i have concerns with security etc. cause I don’t want to add 5 more devices to the insecure IOT cloud that will DDoS someone…
Why this hardware?
- ESP-12E yellow board – it’s cheap, has 4MB flash, all pins nicely available, bunch of leds (one rgb), fotoresistor, power stabilization and battery holder
- DHT11 module – in general I prefer modules over bare sensors, cause I can focus on software instead of soldering and preparing boards – DHT11 is enough for indoor usage, maybe it’s not as accurate as DHT22, but i don’t really care if temperature is 22C or 21.8C, and we have ready python module for handling it
- SSD1306 128×64 OLED display module – again, cheap, cool looking, python module ready
- buttons and wires – just needed this, didn’t really care which one
And maybe the best reason for above – it’s all supported by micropython modules almost out of the box (module names: esp – for board, dht – for sensor, ssd1306 – for screen).
I will be adding more posts under tswarm tag and my projects/tswarm category as the project moves forward. Here is photo of some unpacked modules.