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Parts

Part Voltage Protocol Required
2xMini Breadboard Yes
NodeMCU 5V Yes
BME280 3.3V I2C Yes
SSD1306 3.3V I2C Yes
MB85RC256V 3.3V I2C
CM1107 & CM1106 5V UART Yes

Diagram

Diagram of AirMeter.io device built on two breadboards using a Winsen sensor

Prepare breadboards

To accommodate the dimensions of CO2 sensor and NodeMCU the two breadboards can be clipped together.

First remove the power rail from one side of each breadboard. Then clip the two boards together so that there are no power rails in the center.

Finally place one of the spare power rails that were removed onto the side of the connected boards. This second power rail will be used as the I2C bus.

Use a power rail to connect 3.3V and GND

Connect a 3.3V (+) pin and GND (-) pin of the NodeMCU to an unused power rail +/- pair on the breadboard.

Next connect the matching VCC (3.3V) and GND (-) pins on the components listed below to the matching rail which is connected to the NodeMCU:

Use a another power rail as an I2C bus

Nominate a second power rail pair to use as an I2C bus.

Connect D2 (SCL) on the NodeMCU to one rail in the pair and then connect D1 (SDA) to the other.

Then for each of the components listed below connect the matching SCL and SDA pins to the matching rail connected the corresponding pins on the NodeMCU:

Connect 5V power and GND to Cubic Sensor

This sensor requires a 5V as it's supply voltage. Therefore connect the VCC and GND pins directly to the 5V and GND pins on the NodeMCU.

Connect the Cubic sensor using UART

Connect the RX and TX pins on the CO2 sensor to D8, D7 respectively on the NodeMCU.