Micro:Climate Kit Experiment Guide Datasheet by SparkFun Electronics

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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

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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.

IC Port

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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

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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

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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

•Black to GND

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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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

Soil Temperature

The Soil Temperature block returns the soil a value that you need to

divide by 100 to get the temperature in Celcius. Like the data from the

BME280 sensor in Experiment 1, this is to get you the most accurate

temperature possible.

Set Item To

In this Set Item To block we use a boolean variable of true . You can

then flip flop that variables to false when needed

Not

We use the not block to flip flop a boolean variable when needed. In this

case when a button is pressed.

Show String

The Show String Block enables you to display a scrolling string of

character across the LED array.

Show Number

As in previous experiments we use the show number block to display the

temperature data from the soil temperature sensor.

What You Should See

As soon as you power up your micro:bit, you should see the ground

temperature from the temperature sensor scrolling across the LED array in

Celcius. If you press the A button, it will change what is scrolling to a “Plant”

or “Don’t Plant” depending on the temperature of the ground making it a

useful tool for when to figure out when it is time to plant your tomato crop.

Download

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Note: The actual temperature sensor is at the end of the long wire.

Make sure that is in place where you want to take temperature

readings; otherwise you may get odd values.

Troubleshooting

•Odd temperature — Make sure you are measuring with the end of

the temperature sensor, that is where the actual sensor is.

•Really odd temperature — Double check your wiring and hookup!

•Numbers still seem odd — Check your math blocks! You may be

missing an order of operation.

Experiment 5: Reading the Wind

Direction and Speed

Introduction

The winds are a-blowin'! The question is, which direction and how hard? In

this experiment you will assemble, hook up and program your weather:bit to

read the weather meters — more specifically, the wind anemometer (wind

speed) and directional vane. We will again use the micro:bit’s LED array to

display the wind speed or the direction.

Parts Needed

•1x micro:bit board (Not included)

•1x weather:bit carrier board

•1x micro-B USB cable (Not included)

•1x Weather Meter

micro:climate kit: Exp4

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Suggested Reading

• Reed Switch — A tutorial about how a reed switch works.

• Weather Meter Datasheet — The nitty-gritty details on the weather

meter.

Introducing the Weather Meter (Anemometer and Vane)

The anemometer on the weather meter is the propeller-looking thing that

got lost in a ping-pong ball factory.

It has three cups that catch the wind, which then cause it to spin. As the

head spins, a magnet at the center of the hub travels over a reed switch

that closes the circuit to the pin that the sensor is connected to for a brief

moment. The faster the wind is, the faster the anemometer spins and the

faster and more often the reed switch is triggered.

We count the number of times that the reed switch is triggered every

second, and we can calculate the wind speed from that (1 click per second

is roughly 1.5mph).

We did the hard work on this one in terms of simplifying all of this for you.

All you need to know is that an anemometer is a wind-speed sensor.

The wind vane is the arrow-looking thing that spins.

Weather Meters

SEN-08942

micro:bit Board

DEV-14208

USB Micro-B Cable - 6"

CAB-13244

SparkFun weather:bit

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When the wind blows, it catches the vane, which points in the direction that

the wind is coming from. As the vane moves around, it closes a series of

switches inside, which produce a different resistance at 16 different

locations around the hub. Each direction has a specific value that we have

mapped to the cardinal directions once you have it set in the location you

want it. In the makeCode package the Wind Direction block will return

N,NE,E,SE,S,SW,W,NE directions as a string.

Hardware Hookup

To help you out in the assembly of your weather meter we have created

this step by step assembly guide.

Note: Once you have assembled your weather meter we highly

recommend labeling the two cables for the wind and rain sensors. This

will make your life much easier in the long run!

Once you have completed the assembly of the weather meter, find the

cable for the wind sensors and plug it into the RJ-11 connector on the

weather:bit labeled “wind”.

Weather Meter Hookup Guid

ULY 20, 201

How to assemble your very own weather meter!

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With that you are ready to roll!

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 in.

Code to Note

Start Wind Monitoring

The Start Wind Monitoring block starts all of the necessary processes to

use the wind sensors that plug into the weather:bit. This block show be

placed in the On Start block as it only needs to be called once at the very

beginning of the program.

Show Number

The Show Number block displays/scrolls whatever number is placed inside

of it across the LED array. We use it to display the wind speed in this

example.

Wind Speed

The Wind Speed block is a variable block that returns the calculated wind

speed from the anemometer. It is updated every 2 seconds!

Show String

The Show String block is similar to the Show Number block in that it

displays/scrolls whatever string that it is passed. In this case we use it to

display the wind direction.

Wind Direction

Last but not least, the Wind Direction block is a variable block that returns

a string value of a cardinal direction that the wind vane is pointing.

What You Should See

Download

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Once you power up the micro:bit, spin the anemometer with your hand or

place it in front of a fan. The speed in miles per hour should start to scroll

across the LED array. If you press the A button on your micro:bit, it will

change the readout to print the direction the vane is pointing as the

direction the wind is coming from.

Note: Be sure to set your vane so that N on the micro:bit reading is

true north for this reading to be accurate.

Troubleshooting

•odd readings — Make sure your wiring is correct, make sure the

correct sensors are plugged into the correct RJ11 jack.

•What is north? — The directions produced by the weather:bit are

based off of readings from the vane, you have to personally line up

the orientation of your vane to north.

•It still doesn’t work — Drop us a line, we would love to help you

figure it out!

Experiment 6: Reading the Rain Gauge

Introduction

Rain, rain, go away; come again another day! In this experiment you will

add the rain gauge to your weather meter and use it to track the amount of

rain that falls. In the end you will use the micro:bit to keep track of the

amount of rain, print it out over the LED array when a button is pressed and

then use another button press to reset that value to 0. Ready to get wet?

Us too…

Parts Needed

•1x micro:bit board (Not included)

•1x weather:bit carrier board

•1x micro-B USB cable (Not included)

micro:climate kit: Exp5

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•1x Weather Meter

Suggested Reading

• Weather Meter Datasheet — The nitty-gritty details on the weather

meter.

Introducing the Weather Meter (Rain Gauge)

In the previous experiment you met the wind sensors on the weather meter.

Here you meet the rain gauge!

The rain gauge is actually quite an ingenious design. Inside of the box is a

tiny bucket. When that bucket is full (0.011" of rain) it tips over, both

triggering a switch and dumping out the water that is in the bucket, which

then allows the bucket to come back to upright. So, for every switch press

there is 0.011" of rain. In software we count these triggers and increment

the rainfall value.

Hardware Hookup

If you didn’t assembly your weather meter in the previous experiment we

created this step by step assembly guide for you to follow!

Weather Meters

SEN-08942

micro:bit Board

DEV-14208

USB Micro-B Cable - 6"

CAB-13244

SparkFun weather:bit

DEV-14214

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Page 28 of 36 b Simu‘ator 1 Blocks U JavaScrip\ 2' >300)X loading pvojem. N .t ' .t

Note: Once you have assembled your weather meter we highly

recommend labeling the two cables for the wind and rain sensors. This

will make your life much easier in the long run!

Once you have completed the assembly of the weather meter, find the

cable for the rain gauge and plug it into the RJ-11 connector on the

weather:bit labeled “rain”.

Hope you have an umbrella!

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.

Weather Meter Hookup Guid

ULY 20, 201

How to assemble your very own weather meter!



Page 28 of 3

Page 29 of 36

Code to Note

Start Rain Monitoring

To use the rain gauge you need to add the Start Rain Monitoring block

to your On Start Block for it to be able to function correctly. It sets up the

micro:bit hardware correctly to be able to read the rain gauge correctly.

Rain

The rain block returns the number of inches of rain that the gauge has

measured as a whole number. This variable block stores that value until

your micro:bit is reset or power cycled (turned off and on again).

Show LEDs

We used the Show LEDs block to draw an image of the sun. If MakeCode

doesn’t have just the right icon for you pre-drawn you can make your own

using this method.

Reset

The reset block resets the code that you have on your micro:bit. This is

the same as pressing the reset button on the back of the micro:bit, but at

times it is useful to be able to do this in software. A great example would be

that you couldn’t reach the back of the micro:bit for some reason.

What You Should See

Once you power up your micro:bit, you should see a sun show up on the

LED array. Once the amount of rain fallen goes over 1" the LED array will

display an umbrella and every 10 seconds the number of inches of rain fall

since you started your program.

micro:climate kit: Exp6

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To restart the counter, press the A button or, if you can reach it, the reset

button on the back of the micro:bit.

Troubleshooting

•I am getting a lot or rain? — Every time the bucket tip, it is

measured as rainfall. If you bump into the sensor or if it is vibrated it

may trigger the sensor and you get a false reading.

•Getting an Odd reading?! — Make sure the rain gauge is plugged

into the proper RJ11 jack and there is a “click” when you insert it all

the way.

•It still doesn’t work — Drop us a line, we would love to help you

figure it out!

Experiment 7: Logging to the MicroSD

Card

Introduction

We are almost done with our whirlwind series of weather experiments. In

this final experiment we will look at how to log all of this amazing weather

data to a microSD card using the OpenLog.

Parts Needed

•1x micro:bit board (Not included)

•1x weather:bit carrier board

•1x micro-B USB cable (Not included)

•1x OpenLog (with headers)

•1x microSD card (NOT INCLUDED WITH THIS KIT)

SparkFun OpenLog

DEV-13712

micro:bit Board

DEV-14208

USB Micro-B Cable - 6"

CAB-13244

SparkFun weather:bit

DEV-14214

Page 30 of 3

Page 31 0f36 O O O D o OpenLoqu RENEW“ nu, .. .. .. .. .. ”2 .. . .... ..‘ ..- GQN DXI YXO UCC EN 0 m r. x

Suggested Reading

• OpenLog Hookup Guide — The ups and downs of how to use the

OpenLog

Introducing the SparkFun OpenLog

The OpenLog Data Logger is a simple-to-use open source solution for

logging serial data from your projects. The OpenLog provides a simple

serial interface to log data from a project to a microSD card.

The primary interface with the OpenLog is the FTDI header on the board

edge. This header is designed to plug directly into the weather:bit carrier

board’s serial port, which allows the micro:bit to send data over a serial

connection to the OpenLog.

There are two status LEDs on the OpenLog to help you with

troubleshooting.

MicroSD Card with Adapter -

8GB

COM-11609

Page 31 of 3

Page 32 of 36 I :- aunmmuu I Van-nu...“

•STAT1 — This blue indicator LED toggles on/off when a new

character is received. This LED blinks when serial communication is

functioning.

•STAT2 — This green LED is connected to Arduino D13 (SPI Serial

Clock Line/ATmega328 PB5). This LED only blinks when the SPI

interface is active. You will see it flash when the OpenLog records

512 bytes to the microSD card.

Hardware Hookup

You are going to love this! First thing is that you need to insert a microSD

card into the OpenLog with the text side “up” as shown in the image below.

Make sure the card “clicks” into place and stays in place.

Next insert the OpenLog’s pins into the serial port on the weather:bit carrier

board as shown below. Make sure that all of the pins are aligned and

inserted correctly. Offsetting these pins could end in damaging your

OpenLog or micro:bit. Finally, if you haven’t already, plug your micro:bit into

the weather:bit. With that you should be good to go!

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I) V Simunatnr I}. r/maso’ 1-, mm; (} JavaSnript max \oadmg project ' .t kéfods “gnownlcamw F)! Page 33 of36

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

Serial Redirect To

We use the Serial Port on the weather:bit board to write data to the

SparkFun OpenLog. To do this we need to do some setup for the micro:bit

to use it correctly. We do this through the Serial Redirect To block

placed in our On Start block.

In the Serial Redirect To block we set the transmit (TX) and receive (RX)

pins. In this case we use pins 15 and 14. We also set the baud rate which is

the rate at which two devices “agree” to communicate at. The OpenLog is

preprogrammed to communicate at 9600 baud, so that is what we will set it

at.

Join

The join block is one of the most useful blocks out there. You use it to

join pieces of data together to build a long string that you then store in a

variable. For example for our header we stored comma separated names

Download

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Page 34 of 36

as a single variable called header . The join blocks standard size is 2

slots. To add more slots click on the gear button and drag more slots in

place as you have with the if / else if statements in previous experiments.

Serial Write Line

To send data to the OpenLog we use the Serial Write Line block. This

command sends whatever data you attach to it over the serial lines you

have specified in your Serial Redirect to block with a carriage return at

the end of it.

Running Time(ms)

The running time block returns the number of milliseconds that the

micro:bit has been powered up and running the current program. We are

using it as a timestamp for data logging since there is no access to a

realtime clock.

What You Should See

When you power your micro:bit, you will eventually see an “X” on the LED

array. Press the A button to start logging data every 30 seconds. A check

mark will be displayed on your LED array. Let the program run for a couple

of minutes and press the A button again. You will see an “X” again. It is now

safe to remove the microSD card from the OpenLog.

Now, using the microSD card slot on your computer or an adapter, open up

the microSD card on your computer. You should see two files. One is a

config file, which you can ignore. The other, which has a file name of

“LOGXXXXX.txt,” is what you are looking for; go ahead and open it.

The data in this text file is a Comma Separated Value (CSV) set of the data

you sent it. The format is that the first line is the “header,” which is the

name of each “column.” You see that our header is the following:

time,temperature,humidity,pressure,altitude

The header is followed by lines of values associated with each reading.

In fact, if you are a user of Google Sheets you can import this text file as a

CSV and then graph these values pretty easily. We recommend this quick

guide from Google on how to import a .txt file as a CSV into sheets.

Troubleshooting

•Doesn’t seem to be logging — Make sure your openLog is oriented

correctly in the Serial port

•The log has weird characters —Make sure you have the serial

baud rate set to 9600!

•It still doesn’t work — Drop us a line, we would love to help you

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figure it out!

Resources and Going Further

We produce a number of other kits and carrier boards that you can hook up

to your micro:bit to help take your projects to the next level. Here is some

further reading that may help you along in learning more about the world of

electronics.

For more information on our micro:bit ecosystem, check out these tutorials:

For more Internet-connected weather fun, check out our these other

weather data tutorials.

SparkFun Inventor's Kit for

micro:bit Experiment Guide

This guide contains all the

information you will need to explore

the twelve circuits of the SparkFun

Inventors Kit for micro:bit.

micro:bot Kit Experiment

Guide

Get started with the moto:bit, a

carrier board for the micro:bit that

allows you to control motors, and

create your own robot using this

experiment guide for the micro:bot

kit.

micro:arcade Kit Experiment

Guide

We love games! We love writing

games, building games and yes,

even building game consoles. So we

ant to introduce to you the

micro:arcade kit for the micro:bit!

micro:bit Breakout Board

Hookup Guide

How to get started with the micro:bit

breakout board.

Weather Station Wirelessly

Connected to

Wunderground

Build your own open-source, official

Wunderground weather station that

connects over WiFi via an Electric

Imp.

Photon Weather Shield

Hookup Guide V11

Create Internet-connected weather

projects with the SparkFun Weather

Shield for the Photon.

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er 5 12 1c 11 Page 36 of36 9// 7

rduino Weather Shield

Hookup Guide V1

Read humidity, pressure and

luminosity quickly and easily. Add

ind speed, direction and rain

gauge for full weather station

capabilities.

ESP32 Environment Sensor

Shield Hookup Guide

SparkFun's ESP32 Environment

Sensor Shield provides sensors and

hookups for monitoring

environmental conditions. This

tutorial will show you how to connect

your sensor suite to the Internet and

post weather data online.

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201

https://learn.sparkfun.com/tutorials/microclimat

-kit-experiment-guide/al

Products related to this Datasheet

MICRO CLIMATE KIT

KIT-14217