See also: Enviro + review
The Enviro (£28/$30. Pimoroni)also features the same slimline pHAT form factor to match the size of a Raspberry Pi Zero, although it can be used with any Raspberry Pi model.
Sensing the world
The Enviro’s BME280 weather sensor monitors temperature, barometric pressure, and humidity. As on the Enviro +, this has been positioned at the left edge of the board, away from Raspberry Pi’s CPU, and there’s even a little smile-shaped slot around it to help reduce heat radiated through the board. Even so, you’ll need to adjust its temperature reading for accuracy (by measuring that of the CPU itself and deducting a factor of it).
A smartphone-style LTR-559 light and proximity sensor detects the ambient light level and also proves handy as a substitute for a push-button when you put your finger on it. The board’s tiny MEMs microphone measures sound levels, useful for monitoring noise pollution, and can also be used to record audio.
At the time of writing, most of the code examples provided with the Python library are aimed at the Enviro + Air Quality board. However, it’s easy to edit the code for missing sensors from the all-in-one example to get it showing rolling graphs for temperature, pressure, humidity, and light level on the LCD. There are also a couple of examples that make use of the mic to plot noise levels and frequencies.
If you don’t need to test air quality and just want a simple environmental sensor with a built-in display, the Enviro is ideal. The light sensor could also come in handy for use in IoT setups, such as to trigger your lights to come on when the light level falls below a certain level.
If you also require motion/direction sensing, the original Enviro pHAT is still available (albeit without the mini LCD).
Built-in sensors: BME280 temperature/pressure/humidity, LTR559 light/proximity, SPH0645LM4H-B noise
Display: 0.96-inch colour LCD (160×80)
Dimensions: 65×30×8.5 mm
Lacks the gas sensor of the Enviro + Air Quality board, but features the same mini LCD screen to display your environmental data without a monitor.