Wio Lite W600 IoTwx ATMOS Node

This repository contains the code for running the Wio Lite W600 microcontroller as an ATMOS node in an IoTwx station. This implementation is based on the CircuitPython 5.0 release (January 2020), and requires the BME280 sensor for basic temperature, humidity, pressure and altitude measurements.

Hardware

The ATMOS node is composed of a radiation shield and a connector allowing installation on a 1" PVC pipe constructed stand for the instrument to be seated.

Computer

Any computer with a modern operating system running MacOS, Windows or Linux will work for this installation. You will need the computer to connect the microcontroller for programming the node and uploading the code that reads sensor measurements.

Microcontroller

• Wio Lite W600 ATSAMD21/Cortex M0 micrcontroller
• Wio Lite W600 Grove Shield
• USB-C cable

Sensor

• SeeedStudio Grove BME280 I2C Sensor
• 50-100cm Grove cable

3D-printed Stevenson Radiation Shield

You will need to purchase the filament and have a 3D-printer with at least a 7" base plate to print the standard sized radiation shield.

Software

This node is based on the CircuitPython 5.0.0 Beta 3 release, and uses the Adafruit CircuitPython BME280 library.

Installation, Implementation and Testing

3. Carefully install the W600 onto the Grove shield. NOTE: Do not plug in the W600 USB-C cable at this time — the microcontroller should be unpowered at this time.

4. Power on the W600, inserting the USB cable into your computer and install CircuitPython 5.0 according to the SAMD21 instructions here.

5. Install the BME280 libraries according to the instructions here for installing the CircuitPython Bundle. This is the fastest, easiest way to obtain the drivers.

6. Insert the Grove cable into an available I2C port and attach the BME280 onto the other end.

7. With the W600 connected to your computer, test the sensor with the instructions and code provided in the test folder.

Limitations and Issues

Please post any issues with the software or documentation in the issues area of this repository.

At the time of CirctuitPython 5.0.0, Wifi capabilities are not implemented for this chip. According to the CircuitPython development team, (as of Q1/2020) since the MicroPython libraries are not yet implemented for the full feature set of the SAMD21 M0 chipset functionalities like Wifi, BLE and others are not yet implemented in CircuitPython:

Thus, none of the typical communications capabilities are implemented, but will be integreated when they are available.