Wiring

We will be connecting multiple I2C devices to a single I2C controller using only two wires - SCL and SDA.

• Interested in learning more about I2C Addressing?  Check out our learn guide on connecting multiple I2C devices. 

Make the following connections between the Adafruit Feather Huzzah and the BME280:

• Feather 3V to BME280 Vin
• Feather GND to BME280 GND
• Feather SCL to BME280 SCK
• Feather SDI to BME280 SDI

Make the following connections between the BME280 and the SGP30:

• BME280 SCK to SGP30 SCL
• BME280 SDI to SGP30 SDA
• Feather 3V to SGP30 Vin
• Feather GND to SGP30 GND

Make the following connections between the VEML6070 and the SGP30

• SGP30 SCL to VEML6070 SCL
• SGP30 SDA to VEML6070 SDA
• Feather 3V to VEML6070 Vin
• Feather GND to VEML6070 GND

Assembly

If you'd like to make this portable using the Adafruit Featherwing Proto and a project enclosure, we have some great news, You can fit all the sensors on the FeatherWing Proto. The wiring between the sensors and the feather are identical to the connections made above.

Note: The ACK pin for the VEML6070 is unused, so we're going to hang it off the side so we can fit everything on the board. 

The small plastic project enclosure is the perfect size for a feather and a medium-sized LiPo battery. It's also rugged and has a waterproof gasket seal. 

Connect the Feather Huzzah's JST port to a lipo battery using the included JST connector on the battery:

Next, we're going to test-fit the feather and the lipo battery in the project enclosure. Use a non-permanent marker to outline the positions of the battery and the feather on the bottom of the case.

Put the lid on the box and screw it down to ensure everything fits correctly. Use a ruler and a marker to mark locations for holes on the plastic lid of your project box. Be sure to mark the locations closer to the sensors. 

Let's drill some holes! I used a rotary tool with a 4mm drill bit mounted to a drill press. Be sure to hold the lid tightly, use a low RPM on your tool, and watch your fingers!

Next, we're going to attach a cable gland to seal off the USB cable from the elements. Drill a 5/8" hole on the side of the enclosure where the Feather HUZZAH's USB port is located. The cable gland has integrated screw threads - twist it into the hole you drilled and attach the retaining nut. 

You'll need to cut and splice the Micro USB cable to fit it into the enclosure through the cable gland. Plug a Micro-USB cable into the Feather HUZZAH and your computer. The green CHG LED should turn on to indicate the lipo is charging.

Next, we're going to load the environmental monitoring code on your Feather.