View source for Team11 temperature and humidity sensor

= SENS BME680 Temperature, Humidity, Air Pressure & Gas Sensor =
The SENS BME680 is a temperature, humidity, air pressure and gas (air quality) sensor. The breakout board is equipped with a 3.3V regulator and I2C as well as SPI digital interface. This lets you use it safely with any kind of microcontroller with 3.3V-5V power or logic.

* Temperature - operation range from -40 to 85°C with an accuracy of ±1°C (full accuracy from 0 to 65°C)
* Humidity - operation range from 0 to 100% with an accuracy of ±3%
* Air pressure - operation range from 300 to 1100 hPa with an accuracy of ±1 hPa
* Air quality - a MOX (Metal-oxide) sensor that detects VOCs (like ethanol and carbon monoxide) in the air

== Technical Specifications ==
The SENS BME680 is an I2C and SPI sensor. That means it uses the two I2C/SPI data/clock wires available on most microcontrollers and can share those pins with other sensors as long as they don't have an address collision.

=== Pinout ===
* '''VCC''' – power pin which can take 3-5VDC and safely converts it down using the built-in voltage regulator
* '''GND'''
* '''SCL''' - SCL pin for I2C communication / SCK pin for SPI communication
* '''SDA''' - SDA pin for I2C communication / SDI (MOSI)  pin for SPI communication
* '''SDO''' - SDO (MISO) pin for SPI communication
* '''CS''' - Chip select pin for SPI communication

== Advantages and Disadvantages ==
=== Advantages ===
* Best alternative to the DHT22 sensor which is a popular standard. However, it would be too large/clunky as a smartwatch component
* I2C and SPI bus interface
* 4-in-1 digital sensor

=== Disadvantages ===
* Size 30 x 14 x 10mm
* Relatively heavy (10g) in comparison to similar sensors

= How to get it to work =
== Wiring with an ESP8266 ==
* Connect VCC to the power supply (3-5V is fine) - 3V
* Connect GND to common power/data ground - G
* Connect SCL to the I2C clock SCL pin on your microcontroller - GPIO5 (D1)
* Connect SDA to the I2C data SDA pin on your microcontroller - GPIO4 (D2)

'''[https://i0.wp.com/randomnerdtutorials.com/wp-content/uploads/2020/07/ESP8266-BME680-Environmental-Sensor-Wiring-Diagram-I2C.png?w=831&quality=100&strip=all&ssl=1 See schematic wiring diagram ]'''

== Required Library ==
* Download and save following code as '''[https://raw.githubusercontent.com/RuiSantosdotme/Random-Nerd-Tutorials/master/Projects/ESP-MicroPython/bme680.py bme680.py]'''
* upload library to your microcontroller

== Code Example ==
<syntaxhighlight lang="python" line='line'>

# import modules
from machine import Pin, I2C
from time import sleep
from bme680 import *

# Create sensor object, communicating over the board's default I2C bus
i2c = I2C(scl=Pin(5), sda=Pin(4))
bme = BME680_I2C(i2c=i2c)

# Print out temperature, humidity, air pressure and air quality values
while True:
    temp = str(round(bme.temperature, 2)) + ' °C'
    hum = str(round(bme.humidity, 2)) + ' %'
    pres = str(round(bme.pressure, 2)) + ' hPa'
    gas = str(round(bme.gas/1000, 2)) + ' KOhms'

    print('Temperature:', temp)
    print('Humidity:', hum)
    print('Pressure:', pres)
    print('Gas:', gas)
    print('----------')

    sleep(5)

</syntaxhighlight>

== Instructional Video ==
<youtube>g_oUZPzScyk</youtube>