Simple IoT Weather Station using AllThingsTalk platform, running on Mikroelektronika's Flip&Click (Arduino Due) board.
This project aims to demonstrate integration of Mikroelektronika's hardware components with AllThingsTalk IoT platform.
We're using BME280 all-on-one environmental sensor and ESP8266 to communicate data to cloud based system.
The device is sending temperature, humidity, pressure and derived altitude. There's also a LED actuator which you can toggle from the web to show off push functionality.
- Mikroelektronika's Flip&Click flavor of Arduino Due
- WiFi3 Click board (ESP8266)
- Weather Click board
- USB to Serial TTL Adapter (for flashing the ESP8266)
- Account on AllThingsTalk Maker
While hardware is mostly Plug&Play, some setup is required to get this up and running:
- Male headers need to be soldered to click boards
- 1x8 header needs to be soldered to WiFi3 click board (warning, this is not included in the package), as you'll need it to flash the firmware onto ESP8266. You can use either male or female headers, just make sure to watch the spacing and that it matches your USB-Serial adapter.
WiFi3 Click board is actually a well known inexpensive ESP8266 WiFi SOC in disguise. By default it comes with AT command based firmware for data and connection management. We could use it directly, however as we'd like to use both HTTP and MQTT APIs, implementing those wrappers from scratch over AT commands would probably be both time consuming and prone to bugs, therefore we'll be using espduino project which aims to provide REST and MQTT client over serial, exactly what we need here.
Naturally, if you're so inclined, you can program the ESP8266 using Arduino code directly, as it is supported as one of the Arduino Cores, however we're just going to add connectivity to Flip&Click (Due) board for now.
You can follow this extensive guide on Hackaday to program ESP chip with espduino firmware.
Use esptool or other flasher of your choice (nodemcu-flasher should work too)
esp8266/tools/esptool.py -p COM1 write_flash 0x00000 esp8266/release/0x00000.bin 0x40000 esp8266/release/0x40000.bin
Once flashed, you should be able to verify the ESP8266/espduino works by listening for serial data. It should print out debug information (e.g. MAC address) at the top, simillar to this:
mode : sta(xx:xx:xx:xx:xx:xx)
First, install Arduino IDE. Afterwards, go to Tools > Board > Boards Manager and install Arduino SAM Boards (32-bits ARM Cortex-M3) which will add support for Arduino Due development.
Next, we'll need some libraries. These can be installed either through Sketch > Include Library > Manage Libraries (if available) or by getting master version of library from github and installing it manually.
These libraries are required:
We're using AllThingsTalk as our platform of choice for this IoT project, as we can easily provision custom IoT devices like this one.
After you've created your account on AllThingsTalk Maker, log in, go to Playground if you're not already there.
Navigate to Devices > Make new Device, pick Custom, and name it however you'd like.
You can use Arduino type as well, however, once created, device will contain some preset assets which you can delete as we won't be using them here. There's also an example sketch you could use to get up and running quickly, however it's only usable for regular Arduino projects which have on board connectivity (e.g. Arduino Ethernet or Arduino ESP8266 Core).
Next, make a copy of credentials_sample.h called credentials.h in the same directory and fill in the details (You can find your AllThingsTalk credentials in the right pane of device page).
And... we're all set!
By this point the project should be able to compile without any warnings/errors.
Let's assemble the hardware first:
- Place WiFi3 Click into slot A
- Place Weather Click into slot C
- Connect Flip&Click to your computer using USB cable (make sure you use programming port on Flip&Click, one next to power connector), select appropriate port from Arduino IDE and click
Upload.
You can monitor debug output using Arduino's Serial Monitor. If your WiFi/AllThingsTalk credentials are correct you should see assets appearing on the device page and their data being updated in a real time as they arrive.
You should enable Activity Log from device settings pane if you'd like to retain historical data and plot them on the Activity page.
You can adapt this project to your needs, the Device API is quite simple:
You can add sensors or actuators directly from the device. This is useful in cases where you want devices to provision themselves. Otherwise you can create asset from the web interface and just send/receive data from/to them.
You can use addAsset(name, type, profileType) API, e.g.
// four environmental sensors
device.addAsset(S_TMP, AssetType::sensor, "number");
device.addAsset(S_PSA, AssetType::sensor, "number");
device.addAsset(S_HUM, AssetType::sensor, "number");
device.addAsset(S_ALT, AssetType::sensor, "number");
// and a LED actuator you can toggle
device.addAsset(A_LED, AssetType::actuator, "boolean");Use send(name, value) API to send data to cloud, e.g.:
device.send("Temperature", "10.0");
device.send("Door_Lock", "true");
device.send("Message", "Hello World!");If Command Handler is attached by using device.setCommandHandler(&handler), the handler function will be invoked each time data is sent to your device. You're presented with Command structure which contains name, identifying the asset, and value being value that is sent from Cloud.
Sometimes it's useful for a device to confirm it has in fact received data being sent to it (e.g. so that you could verify it has actually been received). You can either do that manually from Command Handler by calling send(name, value) or setting device.setAutoEcho(true);, as in that case the received value will be sent back immediately.
3D printable bracket is included in the res directory, in case you'd like to have a nice place to keep your weather station, or hang it up on the wall. Uses 3mm holes. Also available on [thingiverse] (http://www.thingiverse.com/thing:1422608).
Have fun!