sparkfun micro climate Kit User manual

micro:climate Kit Experiment Guide
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Introduction to the Micro:Climate Kit
Introduction
We have seen a huge amount of excitement from hobbyists, students and
scientists around building a DIY weather station to track what is going on
around us on Planet Earth on a daily basis.
We have seen just as much excitement around the BBC’s newly released
micro:bit, which made its debut in the United Kingdom and is now available
in the United States through SparkFun.
And then it dawned on us…why not combine the two? So, here it is: a
weather station kit that is built on top of the inexpensive, easy-to-use
micro:bit and Microsoft MakeCode. We have also written seven
experiments that walk you through how to use each and every component
of the kit and how to use them with the micro:bit and Microsoft MakeCode.
What’s Included in the Kit?
Below is all the parts included in the SparkFun micro:climate kit.
The kit comes with everything you need to build a fully featured weather
station for the micro:bit. All you need to supply is, well, the micro:bit!
SparkFun micro:climate kit
KIT-14217
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The kit includes the following parts:
•SparkFun weather:bit — The carrier board for the micro:bit and the
central component to building a weather station
•Weather Meter — Wind speed, direction and rain gauge that
connects to the SparkFun weather:bit
•SparkFun Soil Moisture Sensor — A simple probe for measuring
soil moisture
•Waterproof Temperature Sensor — Waterproof temperature
sensor with a long wire
•SparkFun OpenLog — A small widget that logs any data sent to it
over a serial connection to a microSD card
•10-Pack of M/M 12" Jumper Wires — Jumper wires for connecting
things
•SparkFun Screwdriver — Great for tightening screws and screw
terminals
How to Use This Guide
Please note that this guide is designed to get you started with the
weather:bit board and the SparkFun micro:climate kit in a simple,
straightforward way. We demonstrate each component’s functionality and
the corresponding code to make it work.
While you explore this guide, we urge you to take your time and tinker with
the sensors, code and ideas shared to build something tailored to your
application. Our goal is to get you enough information and know-how to
make you dangerous and then release you into the wild, weather station in
hand, to do whatever you do with a weather station.
Be sure to share your projects with us via Twitter or Facebook! We are
excited to see you get creative and Start Something!
Suggested Reading
Before continuing with this guide, we recommend you be somewhat familiar
with the concepts in the following tutorials:
micro:bit Board
DEV-14208
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Open Source!
All of our experiments and guides are licensed under the Creative
Commons Attribution Share-Alike 4.0 Unported License. Feel free to remix
and reuse our work. But please, share the love and give us attribution for
our hard work!
To view a copy of this license visit this link, or write: Creative Commons,
171 Second Street, Suite 300, San Francisco, CA 94105, USA.
About the weather:bit
The weather:bit is a carrier board for the micro:bit. Similar to an Arduino
shield, it is designed to add functionality to the micro:bit without the hassle
of a number of other boards, components and all of those jumper wires.
In this case, the weather:bit takes your normal run-of-the-mill micro:bit and
turns it into a full-blown weather station with a few extra parts, which you
can use to measure the following:
• Air Temperature
• Relative Humidity
• Barometric Pressure
• Wind Speed
• Wind Direction
• Rain Fall
What is a Circuit
?
Every electrical project starts with a
circuit. Don't know what a circuit is?
We're here to help.
Getting Started with the
micro:bit
The micro:bit is a compact, powerful
programming tool that requires no
software installation. Read on to
learn how to use it YOUR way!
SparkFun weather:bit
DEV-14214
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• Soil Moisture
• Soil Temperature
Phewwwww! That is a lot of data for such a tiny computer! Let’s take a
closer look at this board and check it out for ourselves.
Edge Connector
The weather:bit connects to the micro:bit via an edge pin connector. This
makes it handy to swap out micro:bits for programming, but also gives
reliable connections to all of the different pins on the micro:bit.
BME280 Barometric Pressure Sensor
The weather:bit has a BME280 barometric pressure sensor onboard, which
can measure air temperature, humidity, barometric pressure and altitude. It
communicates with the micro:bit via I C, and the data from this sensor is
easily accessible using the SparkFun weather:bit package for MakeCode.
Weather Meter Sockets
There are two RJ11 jacks at the bottom of the weather:bit. These are used
to connect our weather meters to the weather:bit.
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These meters enable you to measure the wind speed and direction, as well
as rain fall.
Again, these are easily accessible in MakeCode via our SparkFun
weather:bit package.
Soil Moisture and Temperature
Between the two RJ11 jacks are two sets of screw terminals sets.
The one on the left is used to hook up a soil moisture sensor. You can use
either longer jumper wires or wires cut to whatever length works for your
project.
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The set on the right is the soil temperature sensor. It is set up to use our
waterproof temperature sensor. This sensors wire is rather long and is
great for monitoring the temperature of the soil in your garden so that you
know the exact moment the ground is ready for planting those tomatoes!
Serial Port
We have populated the serial port pins with a standard FTDI format to
make it easy for you to plug in a serial widget of your choice, such as an
OpenLog or Serial LCD display, or to just monitor data through an FTDI
breakout and USB cable.
ICPort
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For those of you who are more adventurous and demand a way to hook up
other sensors of your choice, we have added an I C port that can be
soldered to directly — or you can add headers for plug-and-play use of your
I C sensors and actuators.
Installing the weather:bit Package in
MakeCode
To make the most out of the weather:bit with the least amount of coding,
use the MakeCode package we wrote for the weather:bit board.
Packages?
If you have used Arduino before, you probably know about a thing called a
library; which is a collection of code that extends the functionality of the
core programming language. MakeCode packages work the same way.
There are some amazing differences between Arduino libraries and
MakeCode packages. One of them is that MakeCode packages include
JavaScript functions, which you can use when programming in text, as well
as all of the blocks you need to program using the block method. This
makes learning and using new packages straightforward and shortens the
time to awesome when setting out to build the project of your dreams.
Installing a MakeCode Package
To install or add a new package to your MakeCode toolbox (the list of
different block groups), click on “Advanced” and then on “Add Package.”
From here you can search for “SparkFun weather-bit,” and it should show
up as a public package in the list. Go ahead and click on it.
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This will add all of the blocks to your toolbox. In general, this is a bit tricky
as, depending on how the package was written, it may either have its own
toolbox or just add blocks to the existing ones. Take a look at your toolbox;
for the weather:bit you should see…
Great! You have now installed the weather:bit package and are ready to
use the board as well as the components that come in the micro:climate kit.
As a side note, for every new MakeCode project that you make, you will
have to load packages over again. Not a big deal, but noteworthy! Now,
let’s put this package to good use!
Experiment 1: Reading the
Temperature, Humidity and Pressure
Introduction
What comes to mind first when you hear the term “Atmospheric
Conditions”? Well, other than the weatherman on the news, you probably
think about temperature — maybe humidity and even barometric pressure if
you are a weather nerd like many of us at SparkFun. In this first experiment
we will explore measuring those conditions using a micro:bit and the
weather:bit carrier board.
Parts Needed
•1x micro:bit board (Not included)
•1x weather:bit carrier board
•1x micro-B USB cable (Not included)
micro:bit Board
DEV-14208
USB Micro-B Cable - 6"
CAB-13244
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Suggested Reading
• Getting Started with the micro:bit — Basic hookup and programming
of the micro:bit
Introduction to the BME280
The BME280 Atmospheric Sensor is an easy way to measure aspects of
the atmosphere around you, including pressure, humidity and air
temperature. All of this is combined into a petite package that resides on
the weather:bit.
The sensor operates on 3.3V and is super power-efficient, using as little as
5µA (that’s 1/1,000,000 of an amp!) when idling and less than 1mA when
it’s taking measurements. This means you can operate the board on a
battery, with little thought to major power issues.
In this experiment, you will work with the BME280 to read the temperature,
pressure, and humidity of the room as well as your altitude based off of the
atmospheric pressure.
Hardware Hookup
Since the BME280 is already on the weather:bit board, this should be pretty
straightforward; you have one step in hooking everything up. Insert the
micro:bit into the weather:bit carrier board with the LED array facing up as
shown in the image below.
SparkFun weather:bit
DEV-14214
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Note: The edge connector for the micro:bit is not keyed, so there is
the potential for the micro:bit to be inserted backward. Be sure to
check the orientation of the board and micro:bit before plugging it in!
Running Your Script
We are going to use Microsoft MakeCode to program the micro:bit. Please
open a browser window and navigate to https://makecode.microbit.org. This
should open the MakeCode environment that you used to install the
weather:bit package.
Be sure to add the weather:bit package as instructed in the Installing the
weather:bit Package in MakeCode section of this tutorial.
Now, you can either download the following example script and drag and
drop it onto your micro:bit, or use it as an example and build it from scratch
in MakeCode.
Note: If this is your first time programming a micro:bit, please be sure
to see our Getting Started with the micro:bit tutorial on how to get the
MakeCode program onto your micro:bit.
Code to Note
Download
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Start Weather Monitoring
When the script starts, we use this block to start or initiate the BME280
sensor and get it ready to take readings. Anytime you want to use the
temperature, humidity, pressure or altitude blocks, you need to have this
block in your on start block.
Set Item To
We use a variable called item to keep track of which data are being
displayed on the LED array. If item is equal to 0, it shows the temperature;
if 1, it shows the humidity; if 2, the pressure. If the variable goes over 2, we
reset it to 0. We increment the variable by pressing the A button.
Temperature (°C)
This variable returns a number that you then have to divide by 100 to get
the temperature in Celsius.
Humidity
This variable returns a number that you need to divide by 1,024 to get the
relative humidity.
Pressure
This variable returns a number that you divide by 25,600 to get the
atmospheric pressure in hPa.
Why All of the Math?
This is a good question! It all comes down to accuracy of the data that you
receive. MakeCode cannot handle floating point numbers (numbers with
decimal points) yet. Which can be troublesome for getting really accurate
readings from the BME280 with a single variable block. So, to as accurate
of values as possible you have to do some math in the programming
environment. We know, not fun! But, hey now you might pay attention in
math class a bit more now.
What You Should See
Once your code is loaded, you should start to see numbers scroll across
the LED array on your micro:bit, beginning with the temperature in Celsius.
If you press the left button on your micro:bit, the number will change to
percent humidity; press it again, and it will be pressure. Pretty cool…well,
hmmm…maybe warm?
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Troubleshooting
•weather:bit blocks not showing up — Make sure you have a
network connection and have added the package to your MakeCode
environment.
•micro:bit not showing up — Try unplugging the USB cable and
plugging it back in. Also, be sure that you have the cable inserted all
the way into your micro:bit.
•atmospheric data seems odd — Make sure that the BME280 is
free from contact with sources of heat and/or moisture (for example,
having your finger over the top of it).
Experiment 2: Reading the Light Level
Introduction
Light conditions are a huge part of the weather. The great thing is that the
weather:bit doesn’t have a light sensor. No, we didn’t miss a typo! The
weather:bit doesn’t have a light sensor. Why not? Because the micro:bit
has one already! In this experiment you will measure the light around you
and have the micro:bit “graph” it
Parts Needed
For this experiment you actually don’t need the weather:bit carrier board, so
we left it out. But feel free to leave it attached to your micro:bit if you so
choose.
•1x micro:bit board (Not included)
•1x micro-B USB cable (Not included)
micro:climate kit: Exp1
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Suggested Reading
• Using LEDs as Light Sensors — That’s correct! You can use LEDs
as light sensors. In fact, that is how the micro:bit does it.
Hardware Hookup
Again, the hardware hookup here is minimal! Plug your micro:bit into your
computer with the USB cable, and you are good to go!
Running Your Script
Please open a browser window and navigate to makecode.microbit.org.
This should open the MakeCode environment that you used to install the
weather:bit package.
Code to Note
Set lightVal To
We read the light level in the area using the light level block and store it
in a variable called lightVal . This is the value that we can compare
against the calibration value you captured at the beginning of your script.
micro:bit Board
DEV-14208
USB Micro-B Cable - 6
"
CAB-13244
Download
Blocks
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Plot Bar Graph Of
This block is fun! It accepts two values: the value of what you want to graph
and a maximum value of that variable. In this case we want to graph
lightVal , and it has a maximum value of 255 . This will create a “bar
graph” of the light value on your micro:bit.
What You Should See
You should see the LED array light up as a graph based on how bright it is
wherever you are. Turn out the lights or pass your hand over the array, and
the graph should react. Pretty sweet! You now have a way to measure the
light value as well as another way to display data with the micro:bit.
Troubleshooting
•odd light readings — Make sure you are not leaning over the
micro:bit, your shadow will impact the sensor reading.
•The arrows threshold is odd — Try resetting the micro:bit while you
are not leaning over it or casting a shadow on it.
Experiment 3: Reading the Soil
Moisture
Introduction
How wet is the ground? It is actually an important question to ask if you are
thinking about growing plants, digging a hole, or even walking across your
yard. Enter the soil moisture sensor. In this experiment you will hook up the
soil moisture sensor and use it. You will display different images on your
micro:bit based on the moisture level of the soil.
Parts Needed
•1x micro:bit board (Not included)
•1x weather:bit carrier board
•1x micro-B USB cable (Not included)
•3x 12" M/M jumper wires
micro:climate kit: Exp2
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•1x SparkFun Soil Moisture Sensor
Suggested Reading
• Soil Moisture Sensor Hookup Guide — How does the moisture
sensor work?
• Voltage Dividers — The moisture sensor works as a voltage divider.
Dig in and see what makes it tick!
About the Moisture Sensor
micro:bit Board
DEV-14208
SparkFun Soil Moisture
Sensor
SEN-13322
USB Micro-B Cable - 6"
CAB-13244
SparkFun weather:bit
DEV-14214
Jumper Wires Premium 12"
M/M Pack of 10
PRT-09387
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The SparkFun Soil Moisture Sensor is a simple breakout board for
measuring the moisture in soil and similar materials. The soil moisture
sensor is straightforward to use. The two large, exposed pads function as
probes for the sensor, together acting as a variable resistor. The more
water that is in the soil, the better the conductivity between the pads will be,
which will result in a lower resistance and a higher SIG (output voltage).
To get the SparkFun Soil Moisture Sensor functioning with your weather:bit,
all you need to do is connect the VCC, GND and SIG pins to the
weather:bits VCC, GND and SIG screw terminals. You will receive a SIG
out, which will depend on the amount of water in the soil. Oh, and you’ll
also need a bit of dirt in a pot to test it all out!
One commonly known issue with soil moisture sensors is their short life
span when exposed to a moist environment. To combat this, we’ve had the
PCB coated in gold finishing (ENIG, or Electroless Nickel Immersion Gold).
Hardware Hookup
Hooking the moisture sensor up to the weather:bit is relatively easy. You
will need a screwdriver with a small bit, preferably a jeweler’s screwdriver or
our pocket screwdriver.
Pocket Screwdriver Set
TOL-12891
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Start by using the screwdriver to open the three screw terminals on the
moisture sensor enough that you can insert the ends of the jumper wires
into them. Next, insert three jumper wires into the screw terminals using
Red for VCC, Black for GND and Yellow for SIG. Tighten the screws down
so that the wires will not come loose.
Next, do the same thing for the screw terminals for the moisture sensor port
on the weather:bit. Open the screws enough that you can insert the jumper
wires with Red to VCC, Black to GND and Yellow to SIG. Tighten the
screws enough to hold the wires in place.
With that, you are done hooking the moisture sensor up!
Running Your Script
Please open a browser window and navigate to
https://makecode.microbit.org. This should open the MakeCode
environment that you used to install the weather:bit package.
Code to Note
Download
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Soil Moisture
The Soil Moisture block returns an analog value range of 0 - 1023 (a 10
bit number). The lower the number is the less moisture the sensor detects.
The “dryness” and “wetness” level depends on your climate, humidity, etc.
so we cannot give you a concrete range of what is wet and dry, that is
something you will have to fiddle with yourself.
If / Else If / Else
We used an if then block to create some logic that changes based on the
soil moisture detected by the sensor. If the moisture value is low the LED
array shows an angry face, if just right a smiley face and if too wet and
frown.
To add more else / else if options to your if statement click on the small
gear and build your state tree using the block interface presented.
Show Icon
The Show Icon block is really useful when you want to display a simple
image or icon on the LED array. You can select from a number of premade
images from the pull down menu in the block.
What You Should See
Based on our extensive testing (me pouring water into a pot of soil with the
sensor stuck in it), we defined dry, damp and wet states. The image below
shows the experiment powered up to test the plant’s soil.
When you insert your sensor into a potted plant of your own and run your
script, you will see an icon show up on your micro:bit. If you get an angry
face, your soil is too dry; a sad face means it is too wet; and finally, a happy
face is “moist” and just right. Water as needed to keep your plants “happy.”
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You may need to adjust the numbers in your code to match the state of
preference for your house plants!
Troubleshooting
•Odd readings — Make sure your wiring is correct, if you wire the
sensor backwards it will give backwards results.
•I never get a “happy” face — Try playing around with the threshold
values in your if statements to find a range that works for your
application.
•It still doesn’t work — Drop us a line, we would love to help you
figure it out!
Experiment 4: Reading the Soil
Temperature
Introduction
When you are looking to put plants in the ground in spring, plant seed, or
even track the temperature of your koi pond, you need a temperature
sensor. But not just any temperature sensor…a waterproof one! In this
experiment you will explore using the waterproof temperature sensor to
measure ground temperature in a garden or pot.
Parts Needed
•1x micro:bit board (Not included)
•1x weather:bit carrier board
•1x micro-B USB cable (Not included)
•1x Waterproof Temperature Sensor
micro:climate kit: Exp3
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Suggested Reading
• Temperature Sensor Datasheet - The nitty gritty details on the water
proof temperature sensor
• Simple Sketch Video - Video demonstrating the use with Arduino
Hardware Hookup
The hookup of this sensor is much easier with the weather:bit carrier board
than with any other microcontroller. We have done a lot of the leg work for
you!
Find the screw terminals for the soil temperature on the weather:bit. Using
your screwdriver, open the screw terminals a bit and insert the wires as
shown in the photo below with the wires from left to right:
• Red to VCC
• White to SIG
•BlacktoGND
Running Your Script
Temperature Sensor -
Waterproof (DS18B20)
SEN-11050
micro:bit Board
DEV-14208
USB Micro-B Cable - 6"
CAB-13244
SparkFun weather:bit
DEV-14214
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