Adafruit MACROPAD RP2040 Bare Bones, MacroPad RP2040 Starter Kit User Manual

Adafruit MacroPad RP2040

Created by Kattni Rembor

https://learn.adafruit.com/adafruit-macropad-rp2040

Last updated on 2022-01-01 02:40:49 PM EST

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Table of Contents

Overview

Pinouts

• Key Switch Sockets

• Rotary Encoder / BOOT Button

• OLED Display

• NeoPixel LEDs

• RP2040 Microcontroller

• QSPI Flash

• Speaker

• STEMMA QT Connector

• USB C Connector

• Red LED

• Reset Button

• Mounting Bosses

Macropad Assembly

• Switches into Plate

• Connect to Board

• Add Switches

• Backplate

• Keycaps

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CircuitPython

• CircuitPython Quickstart

• Safe Mode

• Flash Resetting UF2

Installing the Mu Editor

• Download and Install Mu

• Starting Up Mu

• Using Mu

Creating and Editing Code

• Creating Code

• Editing Code

• Back to Editing Code...

• Naming Your Program File

Connecting to the Serial Console

• Are you using Mu?

• Serial Console Issues or Delays on Linux

• Setting Permissions on Linux

• Using Something Else?

Interacting with the Serial Console

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The REPL

• Entering the REPL

• Interacting with the REPL

• Returning to the Serial Console

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CircuitPython Libraries

• The Adafruit CircuitPython Library Bundle

• Downloading the Adafruit CircuitPython Library Bundle

• The CircuitPython Community Library Bundle

• Downloading the CircuitPython Community Library Bundle

• Understanding the Bundle

• Example Files

• Copying Libraries to Your Board

• Understanding Which Libraries to Install

• Example: ImportError Due to Missing Library

• Library Install on Non-Express Boards

• Updating CircuitPython Libraries and Examples

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Frequently Asked Questions

Troubleshooting

• Always Run the Latest Version of CircuitPython and Libraries

• I have to continue using CircuitPython 5.x or earlier. Where can I find compatible libraries?

• Bootloader (boardnameBOOT) Drive Not Present

• Windows Explorer Locks Up When Accessing boardnameBOOT Drive

• Copying UF2 to boardnameBOOT Drive Hangs at 0% Copied

• CIRCUITPY Drive Does Not Appear

• Device Errors or Problems on Windows

• Serial Console in Mu Not Displaying Anything

• code.py Restarts Constantly

• CircuitPython RGB Status Light

• CircuitPython 7.0.0 and Later

• CircuitPython 6.3.0 and earlier

• Serial console showing ValueError: Incompatible .mpy file

• CIRCUITPY Drive Issues

• Safe Mode

• To erase CIRCUITPY: storage.erase_filesystem()

• Erase CIRCUITPY Without Access to the REPL

• For the specific boards listed below:

• For SAMD21 non-Express boards that have a UF2 bootloader:

• For SAMD21 non-Express boards that do not have a UF2 bootloader:

• Running Out of File Space on SAMD21 Non-Express Boards

• Delete something!

• Use tabs

• On MacOS?

• Prevent & Remove MacOS Hidden Files

• Copy Files on MacOS Without Creating Hidden Files

• Other MacOS Space-Saving Tips

• Device Locked Up or Boot Looping

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"Uninstalling" CircuitPython

• Backup Your Code

• Moving Circuit Playground Express to MakeCode

• Moving to Arduino

Welcome to the Community!

• Adafruit Discord

• CircuitPython.org

• Adafruit GitHub

• Adafruit Forums

• Read the Docs

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CircuitPython Essentials

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Blink

• LED Location

• Blinking an LED

Digital Input

• LED and Button

• Controlling the LED with a Button

Keypad

MacroPad CircuitPython Library

• MacroPad Library Installation

MacroPad Basics

MacroPad Display Text

MacroPad Display Image

MacroPad Rotation

• Rotation Example

• Other Rotations

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MacroPad Tone

MacroPad Keyboard and Mouse

Macropad MIDI

• Modes

MacroPad Library Docs

Arduino

• Required Libraries

• Example Code

Installing the Earle Philhower core

Connecting your RP2040

Downloads

• Files

• Original MacroPad Demo

• Schematic

• Fab Print

• 3D Model

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Overview

Strap yourself in, we're launching in T-minus 10 seconds...Destination? A new Class M

planet called MACROPAD! M here, stands for Microcontroller because this 3x4

keyboard controller features the newest technology from the Raspberry Pi sector: say

hello to the RP2040. It's speedy little microcontroller with lots of GPIO pins and a 64

times more RAM than the Apollo Guidance Computer. We added 8 MB of flash

memory for plenty of storage.

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Get ready to upgrade your desk's mission control station with a CircuitPython or

Arduino powered Macropad - complete with 12 buttons, OLED display, speaker and

rotary encoder. Customize it for your spacecraft to help guide you through the great

reaches of the unknown. (Or just have it type out your favorite emojis.)

Each of the 12 sockets can accept a Cherry MX-compatible key switch. No soldering

required, just snap it in! Use any key switch you like - but we recommend ones with

slots that will allow the matching twelve NeoPixels underneath to shine through.

This space-ship is also fitted with a 128x64 monochome OLED for a crisp heads-up

display that can be used in Arduino or CircuitPython to display keymaps, stats,

computer performance, etc. There's also a rotary encoder with push-button soldered

in. Twist and turn it or push to change volume or monitor brightness or scroll:

whatever you like! A tiny speaker can give audio feedback or play fun bleepy tunes.

Want to add more hardware? No worries - a STEMMA QT port on the side lets you

connect any I2C add-on peripherals from the massive STEMMA QT / Qwiic family of

plug in boards(https://adafru.it/Qgf).

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Please note, the RP2040 chip does not currently have QMK support - this macropad

is designed to be programmed in Arduino or CircuitPython! If QMK eventually does

add RP2040 as a supported chipset (no ETA and no plans that we know of ), we'll

update this page.

TL;DR?

Raspberry Pi RP2040 Chip + 8MB Flash memory - Dual core Cortex M0+ at

•

~130MHz with 264KB of RAM. Runs CircuitPython, Arduino or MicroPython with

ease and lots of space for development code and files

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USB C Connector for Power/Data - of course this can act as an HID device but

•

also can be MIDI, UART, etc.

3x4 Mechanical key switch sockets - accepts any Cherry MX-compatible

•

switches. Individually tied to GPIO pins (not matrix wired)

One NeoPixel RGB LED per switch, on north side

•

Rotary encoder, 20 detents per rotation, with push-switch on GPIO pin. Push

•

switch is also used for entering bootloader mode when held down on power-up

or reset.

128x64 SH1106 Monochrome OLED display - On high speed hardware SPI port

•

for quick updates

8mm Speaker/Buzzer - With Class D amplifier and RC filter, can be used to make

•

simple beeps and sounds effects.

STEMMA QT Connector - Allows adding any I2C sensors/displays/devices with

•

plug-and-play cables.

Reset button - On the side, for quick restarting of code

•

Four M3 mounting bosses - Make custom enclosures easily

•

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Pinouts

The MacroPad RP2040 is full of macropad deliciousness. It has some great features

beyond the keys. Time for tour!

PDF of the pinouts image above is available here(https://adafru.it/TBk).

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Key Switch Sockets

On the MacroPad, laid out in a 3x4 grid,

are the Cherry-MX compatible key switch

sockets. They are mounted on the back

of the board so the socket points through

to the front. The key switch sockets are

individually tied to GPIO pins (i.e. not

matrix-wired).

Simply press any compatible key switch

into the socket from the top of the board.

You can add a dab of glue to keep the

switch in place; hot glue or a dot of

epoxy will work.

The sockets are available in
CircuitPython as board.KEY1 through
b oard.KEY12 . In Arduino they are pins 1

through 12. Pressing key grounds the pin,

so set a pull-up on each pin.

Rotary Encoder / BOOT Button

We snuck the BOOT button in as the button switch in the rotary encoder. Press

the rotary encoder to engage the BOOT button!

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On the top right corner of the board

(when viewed from the top), is the rotary

encoder / BOOT button. The rotary

encode has 20 detents per rotation. The

BOOT button is required to enter the

bootloader (needed for both

CircuitPython and Arduino), and is also

available as a user input in code. To use

the button, simply press the rotary

encoder down.

The rotary encoder is available in
CircuitPython at board.ROTA or

board.ENCODER_A and board.ROTB or

board.ENCODER_B . It is available in

Arduino as PIN_ROTA and PIN_ROTB .

The BOOT button is available in

CircuitPython at

board.ENCODER_SWITCH or
board.BUTTON . It is available in Arduino

at PIN_SWITCH . Pressing the button

grounds the pin.

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OLED Display

On the top left corner of the board (when

viewed from the top), is the 128x64

SH1106 Monochrome OLED display. The

ribbon cable for the display goes through

a hole in the board to the back, where it

is inserted into the display connector.

This OLED is on high-speed hardware SPI

to ensure quick updates.

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NeoPixel LEDs

Above each set of key switch sockets,

are RGB NeoPixel LEDs laid out in the

same 3x4 grid. These reverse-mount

LEDs are mounted to the back of the

board to shine through to the front (to

allow for the key switches to sit flush

against the front of the board!).

The NeoPixel LEDs are available in
CircuitPython as board.NEOPIXEL . They

are available in Arduino as

PIN_NEOPIXEL .

RP2040 Microcontroller

The large square on the back of the

board, at the top-center, is the RP2040

microcontroller. This is the brain of the

board.

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QSPI Flash

The little square above the RP2040

microcontroller is the 8MB QSPI flash.

QSPI is neat because it allows you to

have 4 data in/out lines instead of just

SPI's single line in and single line out.

This means that QSPI is at least 4 times

faster. But in reality is at least 10x faster

because you can clock the QSPI

peripheral much faster than a plain SPI

peripheral. In CircuitPython, the QSPI

flash is used natively by the interpreter

and is read-only to user code, instead the

flash just shows up as the writable disk

drive!

Speaker

The grey square a bit to the right of the

center of the board on the back is the

8mm speaker/buzzer. With a Class D

amplifier and RC filter, it can be used to

make simple beeps and sounds effects.

The speaker is available in CircuitPython
at board.SPEAKER . It is available in
Arduino at PIN_SPEAKER .

The speaker must be enabled to work in

code. The speaker enable pin in

CircuitPython is

board.SPEAKER_ENABLE . In Arduino, it

is PIN_SPEAKER_ENABLE . Set the pin

high to enable the speaker.

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STEMMA QT Connector

USB C Connector

In the top right corner of the back of the

board, below the mounting boss, is the

STEMMA QT(https://adafru.it/Ft4)

connector. This Qwiic-compatible I2C

connector is designed to make it super

simple to connect up STEMMA QT

sensors and breakouts(https://adafru.it/

Qgf).

At the top-center of the board, visible

from both sides, is the USB Type C

connector. This connector is used both

for transferring data from your computer

(e.g. updating your CircuitPython code.py

file, or uploading an Arduino sketch) and

powering the board.

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Red LED

Reset Button

On the top edge of the back of the

board, to the right of the USB Type C

connector is the red LED. You can control

this in your code.

The red LED is available in CircuitPython
at board.LED . It is available in Arduino
at PIN_LED .

On the right edge of the back of the

board (visible from the front), below the

STEMMA QT connector, is the reset

button. Tap once to reset the board.

When combined with the boot button, the

reset button allows the board to enter

the bootloader.

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Mounting Bosses

Arranged in the top two corners of the

board, and towards the bottom two

corners are four mounting bosses to

allow for using the MacroPad enclosure

kit(https://adafru.it/TAe) or designing

your own enclosures.

Macropad Assembly

The Macropad features hot-swap sockets for the switches -- gone are the days of

having to commit to one type of switch and solder it down! Now, you can plug in your

Cherry MX red keyswitches, use them for a while, get bored, decide its time to test

out some lubed, filmed, re-sprung Invyr Holy Pandas, and swap them just like that!

Switches into Plate

First, insert a couple pf keyswitches

through the keyswitch plate. The plate

mechanically connects the switches to

each other, which lends some nice lateral

stability to the keys.

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Connect to Board

Carefully press the two switches into the

switch sockets, being very careful to

align the legs so none bend!

Add Switches

Continue adding switches, being mindful

of their orientation.

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Backplate

You can add the optional backplate using

four M3 x 6mm screws.

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Keycaps

Now, you can add your keycaps! simply

press them onto the keyswitch stems

until they are fully seated.

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CircuitPython

CircuitPython(https://adafru.it/tB7) is a derivative of MicroPython(https://adafru.it/BeZ)

designed to simplify experimentation and education on low-cost microcontrollers. It

makes it easier than ever to get prototyping by requiring no upfront desktop software

downloads. Simply copy and edit files on the CIRCUITPY drive to iterate.

CircuitPython Quickstart

Follow this step-by-step to quickly get CircuitPython running on your board.

Download the latest version of

CircuitPython for this board via

circuitpython.org

https://adafru.it/TB9

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Click the link above to download the

latest CircuitPython UF2 file.

Save it wherever is convenient for you.

The BOOT button is the button switch in the rotary encoder! To engage the

BOOT button, simply press down on the rotary encoder.

To enter the bootloader, hold down the BOOT/BOOTSEL button (highlighted in red

above), and while continuing to hold it (don't let go!), press and release the reset

button (highlighted in blue above). Continue to hold the BOOT/BOOTSEL button until

the RPI-RP2 drive appears!

If the drive does not appear, release all the buttons, and then repeat the process

above.

You can also start with your board unplugged from USB, press and hold the BOOTSEL

button (highlighted in red above), continue to hold it while plugging it into USB, and

wait for the drive to appear before releasing the button.

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A lot of people end up using charge-only USB cables and it is very frustrating! Make

sure you have a USB cable you know is good for data sync.

You will see a new disk drive appear

called RPI-RP2.



Drag the adafruit_circuitpython_etc.uf2

file to RPI-RP2.

The RPI-RP2 drive will disappear and a

new disk drive called CIRCUITPY will

appear.

That's it, you're done! :)

Safe Mode

You want to edit your code.py or modify the files on your CIRCUITPY drive, but find

that you can't. Perhaps your board has gotten into a state where CIRCUITPY is read-

only. You may have turned off the CIRCUITPY drive altogether. Whatever the reason,

safe mode can help.

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Safe mode in CircuitPython does not run any user code on startup, and disables auto-

reload. This means a few things. First, safe mode bypasses any code in boot.py

(where you can set CIRCUITPY read-only or turn it off completely). Second, it does not

run the code in code.py. And finally, it does not automatically soft-reload when data is

written to the CIRCUITPY drive.

Therefore, whatever you may have done to put your board in a non-interactive state,

safe mode gives you the opportunity to correct it without losing all of the data on the

CIRCUITPY drive.

Entering Safe Mode in CircuitPython 6.x

This section explains entering safe mode on CircuitPython 6.x.

To enter safe mode when using CircuitPython 6.x, plug in your board or hit reset

(highlighted in red above). Immediately after the board starts up or resets, it waits

700ms. On some boards, the onboard status LED (highlighted in green above) will

turn solid yellow during this time. If you press reset during that 700ms, the board will

start up in safe mode. It can be difficult to react to the yellow LED, so you may want to

think of it simply as a slow double click of the reset button. (Remember, a fast double

click of reset enters the bootloader.)

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Entering Safe Mode in CircuitPython 7.x

This section explains entering safe mode on CircuitPython 7.x.

To enter safe mode when using CircuitPython 7.x, plug in your board or hit reset

(highlighted in red above). Immediately after the board starts up or resets, it waits

1000ms. On some boards, the onboard status LED (highlighted in green above) will

blink yellow during that time. If you press reset during that 1000ms, the board will

start up in safe mode. It can be difficult to react to the yellow LED, so you may want to

think of it simply as a slow double click of the reset button. (Remember, a fast double

click of reset enters the bootloader.)

In Safe Mode

Once you've entered safe mode successfully in CircuitPython 6.x, the LED will pulse

yellow.

If you successfully enter safe mode on CircuitPython 7.x, the LED will intermittently

blink yellow three times.

If you connect to the serial console, you'll find the following message.

Auto-reload is off.
Running in safe mode! Not running saved code.

CircuitPython is in safe mode because you pressed the reset button during boot.
Press again to exit safe mode.

Press any key to enter the REPL. Use CTRL-D to reload.

You can now edit the contents of the CIRCUITPY drive. Remember, your code will not

run until you press the reset button, or unplug and plug in your board, to get out of

safe mode.

Flash Resetting UF2

If your board ever gets into a really weird state and doesn't even show up as a disk

drive when installing CircuitPython, try loading this 'nuke' UF2 which will do a 'deep

clean' on your Flash Memory. You will lose all the files on the board, but at least you'll

be able to revive it! After loading this UF2, follow the steps above to re-install

CircuitPython.

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Download flash erasing "nuke" UF2

https://adafru.it/RLE

Installing the Mu Editor

Mu is a simple code editor that works with the Adafruit CircuitPython boards. It's

written in Python and works on Windows, MacOS, Linux and Raspberry Pi. The serial

console is built right in so you get immediate feedback from your board's serial

output!

Mu is our recommended editor - please use it (unless you are an experienced

coder with a favorite editor already!).

Download and Install Mu

Download Mu fromhttps://

codewith.mu(https://adafru.it/Be6).

Click theDownload link for downloads

and installation instructions.

Click Start Hereto find a wealth of other

information, including extensive tutorials

and and how-to's.



Windows users: due to the nature of MSI installers, please remove old versions of

Mu before installing the latest version.

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Starting Up Mu

The first time you start Mu, you will be

prompted to select your 'mode' - you can

always change your mind later. For now

please select CircuitPython!

The current mode is displayed in the

lower right corner of the window, next to

the "gear" icon. If the mode says

"Microbit" or something else, click the

Mode button in the upper left, and then

choose "CircuitPython" in the dialog box

that appears.

Mu attempts to auto-detect your board

on startup, so if you do not have a

CircuitPython board plugged in with a

CIRCUITPY drive available, Mu will inform

you where it will store any code you save

until you plug in a board.

To avoid this warning, plug in a board

and ensure that the CIRCUITPY drive is

mounted before starting Mu.

Using Mu

You can now explore Mu! The three main sections of the window are labeled below;

the button bar, the text editor, and the serial console / REPL.

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Now you're ready to code! Let's keep going...

Creating and Editing Code

One of the best things about CircuitPython is how simple it is to get code up and

running. This section covers how to create and edit your first CircuitPython program.

To create and edit code, all you'll need is an editor. There are many options. Adafruit

strongly recommends using Mu! It's designed for CircuitPython, and it's really simple

and easy to use, with a built in serial console!

If you don't or can't use Mu, there are a number of other editors that work quite well.

The Recommended Editors page(https://adafru.it/Vue) has more details. Otherwise,

make sure you do "Eject" or "Safe Remove" on Windows or "sync" on Linux after

writing a file if you aren't using Mu. (This is not a problem on MacOS.)

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Creating Code

Installing CircuitPython generates a

code.py file on your CIRCUITPY drive. To

begin your own program, open your

editor, and load the code.py file from the

CIRCUITPY drive.

If you are using Mu, click the Load button

in the button bar, navigate to the

CIRCUITPY drive, and choose code.py.

Copy and paste the following code into your editor:

import board
import digitalio
import time

led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

while True:

led.value = True
time.sleep(0.5)
led.value = False
time.sleep(0.5)

The KB2040, QT Py and the Trinkeys do not have a built-in little red LED! There is

an addressable RGB NeoPixel LED. The above example will NOT work on the

KB2040, QT Py or the Trinkeys!

If you're using a KB2040, QT Py or a Trinkey, please download the NeoPixel blink

example(https://adafru.it/UDU).

The NeoPixel blink example uses the onboard NeoPixel, but the time code is the

same. You can use the linked NeoPixel Blink example to follow along with this

guide page.

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It will look like this. Note that under the

while True: line, the next four lines

begin with four spaces to indent them,

and they're indented exactly the same

amount. All the lines before that have no

spaces before the text.

Save the code.py file on your CIRCUITPY

drive.

The little LED should now be blinking. Once per half-second.

Congratulations, you've just run your first CircuitPython program!

On most boards you'll find a tiny red LED.

On the ItsyBitsy nRF52840, you'll find a tiny blue LED.

On QT Py M0, QT Py RP2040, and the Trinkey series, you will find only an RGB

NeoPixel LED.

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Editing Code

To edit code, open thecode.pyfile on

your CIRCUITPY drive into your editor.



Make the desired changes to your code.

Save the file. That's it!

Your code changes are run as soon as the file is done saving.

There's one warning before you continue...

Don't click reset or unplug your board!

The CircuitPython code on your board detects when the files are changed or written

and will automatically re-start your code. This makes coding very fast because you

save, and it re-runs. If you unplug or reset the board before your computer finishes

writing the file to your board, you can corrupt the drive. If this happens, you may lose

the code you've written, so it's important to backup your code to your computer

regularly.

There are a couple of ways to avoid filesystem corruption.

1. Use an editor that writes out the file completely when you save it.

Check out the Recommended Editors page(https://adafru.it/Vue) for details on

different editing options.

If you are dragging a file from your host computer onto the CIRCUITPY drive, you

still need to do step 2. Eject or Sync (below) to make sure the file is completely

written.

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2. Eject or Sync the Drive After Writing

If you are using one of our not-recommended-editors, not all is lost! You can still make

it work.

On Windows, you can Eject or Safe Remove the CIRCUITPY drive. It won't actually

eject, but it will force the operating system to save your file to disk. On Linux, use the

sync command in a terminal to force the write to disk.

You also need to do this if you use Windows Explorer or a Linux graphical file

manager to drag a file onto CIRCUITPY.

Oh No I Did Something Wrong and Now The CIRCUITPY Drive Doesn't Show Up!!!

Don't worry! Corrupting the drive isn't the end of the world (or your board!). If this

happens, follow the steps found on the Troubleshooting(https://adafru.it/Den) page

of every board guide to get your board up and running again.

Back to Editing Code...

Now! Let's try editing the program you added to your board. Open your code.py file
into your editor. You'll make a simple change. Change the first 0.5 to 0.1 . The code

should look like this:

import board
import digitalio
import time

led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

while True:

led.value = True
time.sleep(0.1)
led.value = False
time.sleep(0.5)

Leave the rest of the code as-is. Save your file. See what happens to the LED on your

board? Something changed! Do you know why?

You don't have to stop there! Let's keep going. Change the second 0.5 to 0.1 so it

looks like this:

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while True:
led.value = True
time.sleep(0.1)
led.value = False
time.sleep(0.1)

Now it blinks really fast! You decreased the both time that the code leaves the LED on

and off!

Now try increasing both of the 0.1 to 1 . Your LED will blink much more slowly

because you've increased the amount of time that the LED is turned on and off.

Well done! You're doing great! You're ready to start into new examples and edit them

to see what happens! These were simple changes, but major changes are done using

the same process. Make your desired change, save it, and get the results. That's

really all there is to it!

Naming Your Program File

CircuitPython looks for a code file on the board to run. There are four options: code.t

xt, code.py, main.txt and main.py. CircuitPython looks for those files, in that order, and

then runs the first one it finds. While code.py is the recommended name for your code

file, it is important to know that the other options exist. If your program doesn't seem

to be updating as you work, make sure you haven't created another code file that's

being read instead of the one you're working on.

Connecting to the Serial Console

One of the staples of CircuitPython (and programming in general!) is something called

a "print statement". This is a line you include in your code that causes your code to

output text. A print statement in CircuitPython (and Python) looks like this:

print("Hello, world!")

This line in your code.py would result in:

Hello, world!

However, these print statements need somewhere to display. That's where the serial

console comes in!

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The serial console receives output from your CircuitPython board sent over USB and

displays it so you can see it. This is necessary when you've included a print statement

in your code and you'd like to see what you printed. It is also helpful for

troubleshooting errors, because your board will send errors and the serial console will

display those too.

The serial console requires an editor that has a built in terminal, or a separate

terminal program. A terminal is a program that gives you a text-based interface to

perform various tasks.

Are you using Mu?

If so, good news! The serial consoleis built into Mu and willautodetect your board

making using the serial console really really easy.

First, make sure your CircuitPython board

is plugged in.

If you open Mu without a board plugged

in, you may encounter the error seen

here, letting you know no CircuitPython

board was found and indicating where

your code will be stored until you plug in

a board.

If you are using Windows 7, make sure

you installed the drivers(https://adafru.it/

VuB).

Once you've opened Mu with your board plugged in, look for the Serial button in the

button bar and click it.

The Mu window will split in two, horizontally, and display the serial console at the

bottom.

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If nothing appears in the serial console, it may mean your code is done running

or has no print statements in it. Click into the serial console part of Mu, and press

CTRL+D to reload.

Serial Console Issues or Delays on Linux

If you're on Linux, and are seeing multi-second delays connecting to the serial
console, or are seeing "AT" and other gibberish when you connect, then the modemma

nager service might be interfering. Just remove it; it doesn't have much use unless

you're still using dial-up modems.

To remove modemmanager , type the following command at a shell:

sudo apt purge modemmanager

Setting Permissions on Linux

On Linux, if you see an error box something like the one below when you press the S

erial button, you need to add yourself to a user group to have permission to connect

to the serial console.

On Ubuntu and Debian, add yourself to the dialout group by doing:

sudo adduser $USER dialout

After running the command above, reboot your machine to gain access to the group.

On other Linux distributions, the group you need may be different. See the Advanced

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Serial Console on Linux(https://adafru.it/VAO)for details on how to add yourself to

the right group.

Using Something Else?

If you're not using Mu to edit, are using or if for some reason you are not a fan of its

built in serial console, you can run the serial console from a separate program.

Windows requires you to download a terminal program. Check out the Advanced

Serial Console on Windows page for more details.(https://adafru.it/AAH)

MacOS has Terminal built in, though there are other options available for download. C

heck the Advanced Serial Console on Mac page for more details.(https://adafru.it/

AAI)

Linux has a terminal program built in, though other options are available for

download. Check the Advanced Serial Console on Linux page for more details.(https:

//adafru.it/VAO)

Once connected, you'll see something like the following.

Interacting with the Serial Console

Once you've successfully connected to the serial console, it's time to start using it.

The code you wrote earlier has no output to the serial console. So, you're going to

edit it to create some output.

Open your code.py file into your editor, and include a print statement. You can print

anything you like! Just include your phrase between the quotation marks inside the

parentheses. For example:

import board
import digitalio
import time

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led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

while True:

print("Hello, CircuitPython!")
led.value = True
time.sleep(1)
led.value = False
time.sleep(1)

Save your file.

Now, let's go take a look at the window with our connection to the serial console.

Excellent! Our print statement is showing up in our console! Try changing the printed

text to something else.

import board
import digitalio
import time

led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

while True:

print("Hello back to you!")
led.value = True
time.sleep(1)
led.value = False
time.sleep(1)

Keep your serial console window where you can see it. Save your file. You'll see what

the serial console displays when the board reboots. Then you'll see your new change!

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The Traceback (most recent call last): is telling you the last thing your board

was doing before you saved your file. This is normal behavior and will happen every

time the board resets. This is really handy for troubleshooting. Let's introduce an error

so you can see how it is used.

Delete the e at the end of True from the line led.value = True so that it says le

d.value = Tru

import board
import digitalio
import time

led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

while True:

print("Hello back to you!")
led.value = Tru
time.sleep(1)
led.value = False
time.sleep(1)

Save your file. You will notice that your red LED will stop blinking, and you may have a

colored status LED blinking at you. This is because the code is no longer correct and

can no longer run properly. You need to fix it!

Usually when you run into errors, it's not because you introduced them on purpose.

You may have 200 lines of code, and have no idea where your error could be hiding.

This is where the serial console can help. Let's take a look!

The Traceback (most recent call last): is telling you that the last thing it was
able to run was line 10 in your code. The next line is your error: NameError: name

'Tru' is not defined . This error might not mean a lot to you, but combined with

knowing the issue is on line 10, it gives you a great place to start!

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Go back to your code, and take a look at line 10. Obviously, you know what the

problem is already. But if you didn't, you'd want to look at line 10 and see if you could

figure it out. If you're still unsure, try googling the error to get some help. In this case,

you know what to look for. You spelled True wrong. Fix the typo and save your file.

Nice job fixing the error! Your serial console is streaming and your red LED Is blinking

again.

The serial console will display any output generated by your code. Some sensors,

such as a humidity sensor or a thermistor, receive data and you can use print

statements to display that information. You can also use print statements for

troubleshooting, which is called "print debugging". Essentially, if your code isn't

working, and you want to know where it's failing, you can put print statements in

various places to see where it stops printing.

The serial console has many uses, and is an amazing tool overall for learning and

programming!

The REPL

The other feature of the serial connection is the Read-Evaluate-Print-Loop, or REPL.

The REPL allows you to enter individual lines of code and have them run immediately.

It's really handy if you're running into trouble with a particular program and can't

figure out why. It's interactive so it's great for testing new ideas.

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Entering the REPL

To use the REPL, you first need to be connected to the serial console. Once that

connection has been established, you'll want to press CTRL+C.

If there is code running, in this case code measuring distance, it will stop and you'll
see Press any key to enter the REPL. Use CTRL-D to reload. Follow those

instructions, and press any key on your keyboard.

The Traceback (most recent call last): is telling you the last thing your board
was doing before you pressed Ctrl + C and interrupted it. The KeyboardInterrupt

is you pressing CTRL+C. This information can be handy when troubleshooting, but for

now, don't worry about it. Just note that it is expected behavior.

If your code.py file is empty or does not contain a loop, it will show an empty output
and Code done running. . There is no information about what your board was

doing before you interrupted it because there is no code running.

If you have no code.py on your CIRCUITPY drive, you will enter the REPL immediately

after pressing CTRL+C. Again, there is no information about what your board was

doing before you interrupted it because there is no code running.

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Regardless, once you press a key you'll see a >>> prompt welcoming you to the

REPL!

If you have trouble getting to the >>> prompt, try pressing Ctrl + C a few more times.

The first thing you get from the REPL is information about your board.

This line tells you the version of CircuitPython you're using and when it was released.

Next, it gives you the type of board you're using and the type of microcontroller the

board uses. Each part of this may be different for your board depending on the

versions you're working with.

This is followed by the CircuitPython prompt.

Interacting with the REPL

From this prompt you can run all sorts of commands and code. The first thing you'll do
is run help() . This will tell you where to start exploring the REPL. To run code in the

REPL, type it in next to the REPL prompt.

Type help() next to the prompt in the REPL.

Then press enter. You should then see a message.

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First part of the message is another reference to the version of CircuitPython you're

using. Second, a URL for the CircuitPython related project guides. Then... wait. What's
this? To list built-in modules type `help("modules")`. Remember the

modules you learned about while going through creating code? That's exactly what

this is talking about! This is a perfect place to start. Let's take a look!

Type help("modules") into the REPL next to the prompt, and press enter.

This is a list of all the core modules built into CircuitPython, including board .
Remember, board contains all of the pins on the board that you can use in your

code. From the REPL, you are able to see that list!

Type import board into the REPL and press enter. It'll go to a new prompt. It might
look like nothing happened, but that's not the case! If you recall, the import

statement simply tells the code to expect to do something with that module. In this

case, it's telling the REPL that you plan to do something with that module.

Next, type dir(board) into the REPL and press enter.

This is a list of all of the pins on your board that are available for you to use in your

code. Each board's list will differ slightly depending on the number of pins available.
Do you see LED ? That's the pin you used to blink the red LED!

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The REPL can also be used to run code. Be aware that any code you enter into the

REPL isn't saved anywhere. If you're testing something new that you'd like to keep,

make sure you have it saved somewhere on your computer as well!

Every programmer in every programming language starts with a piece of code that

says, "Hello, World." You're going to say hello to something else. Type into the REPL:

print("Hello, CircuitPython!")

Then press enter.

That's all there is to running code in the REPL! Nice job!

You can write single lines of code that run stand-alone. You can also write entire

programs into the REPL to test them. Remember that nothing typed into the REPL is

saved.

There's a lot the REPL can do for you. It's great for testing new ideas if you want to

see if a few new lines of code will work. It's fantastic for troubleshooting code by

entering it one line at a time and finding out where it fails. It lets you see what

modules are available and explore those modules.

Try typing more into the REPL to see what happens!

Everything typed into the REPL is ephemeral. Once you reload the REPL or return

to the serial console, nothing you typed will be retained in any memory space. So

be sure to save any desired code you wrote somewhere else, or you'll lose it

when you leave the current REPL instance!

Returning to the Serial Console

When you're ready to leave the REPL and return to the serial console, simply press CT

RL+D. This will reload your board and reenter the serial console. You will restart the

program you had running before entering the REPL. In the console window, you'll see

any output from the program you had running. And if your program was affecting

anything visual on the board, you'll see that start up again as well.

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You can return to the REPL at any time!

CircuitPython Libraries

As CircuitPython development continues and there are new releases, Adafruit

will stop supporting older releases. Visit https://circuitpython.org/downloads to

download the latest version of CircuitPython for your board. You must download

the CircuitPython Library Bundle that matches your version of CircuitPython.

Please update CircuitPython and then visit https://circuitpython.org/libraries to

download the latest Library Bundle.

Each CircuitPython program you run needs to have a lot of information to work. The

reason CircuitPython is so simple to use is that most of that information is stored in

other files and works in the background. These files are called libraries. Some of them

are built into CircuitPython. Others are stored on your CIRCUITPY drive in a folder

called lib. Part of what makes CircuitPython so great is its ability to store code

separately from the firmware itself. Storing code separately from the firmware makes

it easier to update both the code you write and the libraries you depend.

Your board may ship with a lib folder already, it's in the base directory of the drive. If

not, simply create the folder yourself. When you first install CircuitPython, an empty lib

directory will be created for you.

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CircuitPython libraries work in the same way as regular Python modules so the Python

docs(https://adafru.it/rar) are an excellent reference for how it all should work. In

Python terms, you can place our library files in the lib directory because it's part of the

Python path by default.

One downside of this approach of separate libraries is that they are not built in. To

use them, one needs to copy them to the CIRCUITPY drive before they can be used.

Fortunately, there is a library bundle.

The bundle and the library releases on GitHub also feature optimized versions of the

libraries with the .mpy file extension. These files take less space on the drive and

have a smaller memory footprint as they are loaded.

Due to the regular updates and space constraints, Adafruit does not ship boards with

the entire bundle. Therefore, you will need to load the libraries you need when you

begin working with your board. You can find example code in the guides for your

board that depends on external libraries.

Either way, as you start to explore CircuitPython, you'll want to know how to get

libraries on board.

The Adafruit CircuitPython Library Bundle

Adafruit provides CircuitPython libraries for much of the hardware they provide,

including sensors, breakouts and more. To eliminate the need for searching for each

library individually, the libraries are available together in the Adafruit CircuitPython

Library Bundle. The bundle contains all the files needed to use each library.

Downloading the Adafruit CircuitPython Library Bundle

You can download the latest Adafruit CircuitPython Library Bundle release by clicking

the button below. The libraries are being constantly updated and improved, so you'll

always want to download the latest bundle.

Match up the bundle version with the version of CircuitPython you are running. For

example, you would download the 6.x library bundle if you're running any version of

CircuitPython 6, or the 7.x library bundle if you're running any version of CircuitPython

7, etc. If you mix libraries with major CircuitPython versions, you will get incompatible

mpy errors due to changes in library interfaces possible during major version

changes.

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Click to visit circuitpython.org for the

latest Adafruit CircuitPython Library

Bundle

https://adafru.it/ENC

Download the bundle version that matches your CircuitPython firmware version. If you

don't know the version, check the version info in boot_out.txt file on the CIRCUITPY

drive, or the initial prompt in the CircuitPython REPL. For example, if you're running

v7.0.0, download the 7.x library bundle.

There's also a py bundle which contains the uncompressed python files, you probably

don't want that unless you are doing advanced work on libraries.

The CircuitPython Community Library Bundle

The CircuitPython Community Library Bundle is made up of libraries written and

provided by members of the CircuitPython community. These libraries are often

written when community members encountered hardware not supported in the

Adafruit Bundle, or to support a personal project. The authors all chose to submit

these libraries to the Community Bundle make them available to the community.

These libraries are maintained by their authors and are not supported by Adafruit. As

you would with any library, if you run into problems, feel free to file an issue on the

GitHub repo for the library. Bear in mind, though, that most of these libraries are

supported by a single person and you should be patient about receiving a response.

Remember, these folks are not paid by Adafruit, and are volunteering their personal

time when possible to provide support.

Downloading the CircuitPython Community Library Bundle

You can download the latest CircuitPython Community Library Bundle release by

clicking the button below. The libraries are being constantly updated and improved,

so you'll always want to download the latest bundle.

Click for the latest CircuitPython

Community Library Bundle release

https://adafru.it/VCn

The link takes you to the latest release of the CircuitPython Community Library

Bundle on GitHub. There are multiple versions of the bundle available. Download the

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bundle version that matches your CircuitPython firmware version. If you don't know

the version, check the version info in boot_out.txt file on the CIRCUITPY drive, or the

initial prompt in the CircuitPython REPL. For example, if you're running v7.0.0,

download the 7.x library bundle.

Understanding the Bundle

After downloading the zip, extract its contents. This is usually done by double clicking

on the zip. On Mac OSX, it places the file in the same directory as the zip.

Open the bundle folder. Inside you'll find two information files, and two folders. One

folder is the lib bundle, and the other folder is the examples bundle.

Now open the lib folder. When you open the folder, you'll see a large number of .mpy

files, and folders.

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Example Files

All example files from each library are now included in the bundles in an examples

directory (as seen above), as well as an examples-only bundle. These are included for

two main reasons:

Allow for quick testing of devices.

•

Provide an example base of code, that is easily built upon for individualized

•

purposes.

Copying Libraries to Your Board

First open the lib folder on your CIRCUITPY drive. Then, open the lib folder you

extracted from the downloaded zip. Inside you'll find a number of folders and .mpy

files. Find the library you'd like to use, and copy it to the lib folder on CIRCUITPY.

If the library is a directory with multiple .mpy files in it, be sure to copy the entire

folder to CIRCUITPY/lib.

This also applies to example files. Open the examples folder you extracted from the

downloaded zip, and copy the applicable file to your CIRCUITPY drive. Then, rename

it to code.py to run it.

If a library has multiple .mpy files contained in a folder, be sure to copy the entire

folder to CIRCUITPY/lib.

Understanding Which Libraries to Install

You now know how to load libraries on to your CircuitPython-compatible

microcontroller board. You may now be wondering, how do you know which libraries

you need to install? Unfortunately, it's not always straightforward. Fortunately, there is

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an obvious place to start, and a relatively simple way to figure out the rest. First up:

the best place to start.

When you look at most CircuitPython examples, you'll see they begin with one or
more import statements. These typically look like the following:

import library_or_module

•

However, import statements can also sometimes look like the following:

from library_or_module import name

•

from library_or_module.subpackage import name

•

from library_or_module import name as local_name

•

They can also have more complicated formats, such as including a try / except

block, etc.

The important thing to know is that an import statement will always include the

name of the module or library that you're importing.

Therefore, the best place to start is by reading through the import statements.

Here is an example import list for you to work with in this section. There is no setup or

other code shown here, as the purpose of this section involves only the import list.

import time
import board
import neopixel
import adafruit_lis3dh
import usb_hid
from adafruit_hid.consumer_control import ConsumerControl
from adafruit_hid.consumer_control_code import ConsumerControlCode

Keep in mind, not all imported items are libraries. Some of them are almost always

built-in CircuitPython modules. How do you know the difference? Time to visit the

REPL.

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In the Interacting with the REPL section(https://adafru.it/Awz) on The REPL page(http

s://adafru.it/Awz) in this guide, the help("modules") command is discussed. This

command provides a list of all of the built-in modules available in CircuitPython for

your board. So, if you connect to the serial console on your board, and enter the
REPL, you can run help("modules") to see what modules are available for your
board. Then, as you read through the import statements, you can, for the purposes

of figuring out which libraries to load, ignore the statement that import modules.

The following is the list of modules built into CircuitPython for the Feather RP2040.

Your list may look similar or be anything down to a significant subset of this list for

smaller boards.

Now that you know what you're looking for, it's time to read through the import
statements. The first two, time and board , are on the modules list above, so they're

built-in.

The next one, neopixel , is not on the module list. That means it's your first library!

So, you would head over to the bundle zip you downloaded, and search for neopixel.

There is a neopixel.mpy file in the bundle zip. Copy it over to the lib folder on your CI
RCUITPY drive. The following one, adafruit_lis3dh , is also not on the module list.

Follow the same process for adafruit_lis3dh, where you'll find adafruit_lis3dh.mpy,

and copy that over.

The fifth one is usb_hid , and it is in the modules list, so it is built in. Often all of the

built-in modules come first in the import list, but sometimes they don't! Don't assume

that everything after the first library is also a library, and verify each import with the

modules list to be sure. Otherwise, you'll search the bundle and come up empty!

The final two imports are not as clear. Remember, when import statements are
formatted like this, the first thing after the from is the library name. In this case, the
library name is adafruit_hid . A search of the bundle will find an adafruit_hid folder.

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When a library is a folder, you must copy the entire folder and its contentsas it is in

the bundle to the lib folder on your CIRCUITPY drive. In this case, you would copy the

entire adafruit_hid folder to your CIRCUITPY/lib folder.

Notice that there are two imports that begin with adafruit_hid . Sometimes you will

need to import more than one thing from the same library. Regardless of how many

times you import the same library, you only need to load the library by copying over

the adafruit_hid folder once.

That is how you can use your example code to figure out what libraries to load on

your CircuitPython-compatible board!

There are cases, however, where libraries require other libraries internally. The

internally required library is called a dependency. In the event of library

dependencies, the easiest way to figure out what other libraries are required is to
connect to the serial console and follow along with the ImportError printed there.
The following is a very simple example of an ImportError , but the concept is the

same for any missing library.

Example: ImportError Due to Missing Library

If you choose to load libraries as you need them, or you're starting fresh with an

existing example, you may end up with code that tries to use a library you haven't yet

loaded. This section will demonstrate what happens when you try to utilise a library

that you don't have loaded on your board, and cover the steps required to resolve the

issue.

This demonstration will only return an error if you do not have the required library

loaded into the lib folder on your CIRCUITPY drive.

Let's use a modified version of the Blink example.

import board
import time
import simpleio

led = simpleio.DigitalOut(board.LED)

while True:
led.value = True
time.sleep(0.5)
led.value = False
time.sleep(0.5)

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Save this file. Nothing happens to your board. Let's check the serial console to see

what's going on.

You have an ImportError . It says there is no module named 'simpleio' . That's

the one you just included in your code!

Click the link above to download the correct bundle. Extract the lib folder from the

downloaded bundle file. Scroll down to find simpleio.mpy. This is the library file you're

looking for! Follow the steps above to load an individual library file.

The LED starts blinking again! Let's check the serial console.

No errors! Excellent. You've successfully resolved an ImportError !

If you run into this error in the future, follow along with the steps above and choose

the library that matches the one you're missing.

Library Install on Non-Express Boards

If you have an M0 non-Express board such as Trinket M0, Gemma M0, QT Py M0, or

one of the M0 Trinkeys, you'll want to follow the same steps in the example above to
install libraries as you need them. Remember, you don't need to wait for an ImportE

rror if you know what library you added to your code. Open the library bundle you

downloaded, find the library you need, and drag it to the lib folder on your CIRCUITPY

drive.

You can still end up running out of space on your M0 non-Express board even if you

only load libraries as you need them. There are a number of steps you can use to try

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to resolve this issue. You'll find suggestions on the Troubleshooting page(https://

adafru.it/Den).

Updating CircuitPython Libraries and Examples

Libraries and examples are updated from time to time, and it's important to update the

files you have on your CIRCUITPY drive.

To update a single library or example, follow the same steps above. When you drag

the library file to your lib folder, it will ask if you want to replace it. Say yes. That's it!

A new library bundle is released every time there's an update to a library. Updates

include things like bug fixes and new features. It's important to check in every so

often to see if the libraries you're using have been updated.

Frequently Asked Questions

These are some of the common questions regarding CircuitPython and CircuitPython

microcontrollers.

As CircuitPython development continues and there are new releases, Adafruit

will stop supporting older releases. Visit https://circuitpython.org/downloads to

download the latest version of CircuitPython for your board. You must download

the CircuitPython Library Bundle that matches your version of CircuitPython.

Please update CircuitPython and then visit https://circuitpython.org/libraries to

download the latest Library Bundle.

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I have to continue using CircuitPython 6.x or earlier. Where can I find compatible libraries?

We are no longer building or supporting the CircuitPython 6.x or earlier library

bundles. We highly encourage you to update CircuitPython to the latest

version(https://adafru.it/Em8) and use the current version of the libraries(https://

adafru.it/ENC). However, if for some reason you cannot update, here are the last

available library bundles for older versions:

2.x bundle(https://adafru.it/FJA)

•

3.x bundle(https://adafru.it/FJB)

•

4.x bundle(https://adafru.it/QDL)

•

5.x bundle(https://adafru.it/QDJ)

•

6.x bundle(https://adafru.it/Xmf )

•

Is ESP8266 or ESP32 supported in CircuitPython? Why not?

We dropped ESP8266 support as of 4.x - For more information please read about it

here(https://adafru.it/CiG)!

We do not support ESP32 because it does not have native USB.

We do support ESP32-S2, which has native USB.

How do I connect to the Internet with CircuitPython?

If you'd like to include WiFi in your project, check out this guide(https://adafru.it/

F5X) on using AirLift with CircuitPython. For further project examples, and guides

about using AirLift with specific hardware, check out the Adafruit Learn

System(https://adafru.it/VBr).

Is there asyncio support in CircuitPython?

There is preliminary support for asyncio starting with CircuitPython 7.1.0. Read

about using it in the Cooperative Multitasking in CircuitPython(https://adafru.it/

XnA) Guide.

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My RGB NeoPixel/DotStar LED is blinking funny colors ­what does it mean?

The status LED can tell you what's going on with your CircuitPython board. Read

more here for what the colors mean!(https://adafru.it/Den)

What is a MemoryError?

Memory allocation errors happen when you're trying to store too much on the

board. The CircuitPython microcontroller boards have a limited amount of memory

available. You can have about 250 lines of code on the M0 Express boards. If you
try to import too many libraries, a combination of large libraries, or run a program

with too many lines of code, your code will fail to run and you will receive a

MemoryError in the serial console.

What do I do when I encounter a MemoryError?

Try resetting your board. Each time you reset the board, it reallocates the memory.

While this is unlikely to resolve your issue, it's a simple step and is worth trying.

Make sure you are using .mpy versions of libraries. All of the CircuitPython libraries

are available in the bundle in a .mpy format which takes up less memory than .py

format. Be sure that you're using the latest library bundle(https://adafru.it/uap) for

your version of CircuitPython.

If that does not resolve your issue, try shortening your code. Shorten comments,

remove extraneous or unneeded code, or any other clean up you can do to

shorten your code. If you're using a lot of functions, you could try moving those

into a separate library, creating a .mpy of that library, and importing it into your

code.

You can turn your entire file into a .mpy and import that into code.py. This means

you will be unable to edit your code live on the board, but it can save you space.

Can the order of my import statements affect memory?

It can because the memory gets fragmented differently depending on allocation

order and the size of objects. Loading .mpy files uses less memory so its

recommended to do that for files you aren't editing.

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How can I create my own .mpy files?

You can make your own .mpy versions of files with mpy-cross .

You can download mpy-cross for your operating system from here(https://

adafru.it/QDK). Builds are available for Windows, macOS, x64 Linux, and Raspberry

Pi Linux. Choose the latest mpy-cross whose version matches the version of

CircuitPython you are using.

To make a .mpy file, run ./mpy-cross path/to/yourfile.py to create a

yourfile.mpy in the same directory as the original file.

How do I check how much memory I have free?

Run the following to see the number of bytes available for use:

import gc
gc.mem_free()

Does CircuitPython support interrupts?

No. CircuitPython does not currently support interrupts. We do not have an

estimated time for when they will be included

Does Feather M0 support WINC1500?

No, WINC1500 will not fit into the M0 flash space.

Can AVRs such as ATmega328 or ATmega2560 run CircuitPython?

No.

Commonly Used Acronyms

CP or CPy = CircuitPython(https://adafru.it/KJD)

CPC = Circuit Playground Classic(https://adafru.it/ncE)

CPX = Circuit Playground Express(https://adafru.it/wpF)

CPB = Circuit Playground Bluefruit(https://adafru.it/Gpe)

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Troubleshooting

From time to time, you will run into issues when working with CircuitPython. Here are

a few things you may encounter and how to resolve them.

As CircuitPython development continues and there are new releases, Adafruit

will stop supporting older releases. Visit https://circuitpython.org/downloads to

download the latest version of CircuitPython for your board. You must download

the CircuitPython Library Bundle that matches your version of CircuitPython.

Please update CircuitPython and then visit https://circuitpython.org/libraries to

download the latest Library Bundle.

Always Run the Latest Version of CircuitPython and Libraries

As CircuitPython development continues and there are new releases, Adafruit will

stop supporting older releases. You need to update to the latest CircuitPython.(https:

//adafru.it/Em8).

You need to download the CircuitPython Library Bundle that matches your version of

CircuitPython. Please update CircuitPython and then download the latest bundle(http

s://adafru.it/ENC).

As new versions of CircuitPython are released, Adafruit will stop providing the

previous bundles as automatically created downloads on the Adafruit CircuitPython

Library Bundle repo. If you must continue to use an earlier version, you can still
download the appropriate version of mpy-cross from the particular release of

CircuitPython on the CircuitPython repo and create your own compatible .mpy library

files. However, it is best to update to the latest for both CircuitPython and the library

bundle.

I have to continue using CircuitPython 5.x or earlier. Where can I find compatible libraries?

Adafruit is no longer building or supporting the CircuitPython 5.x or earlier library

bundles. You are highly encourged to update CircuitPython to the latest version(http

s://adafru.it/Em8) and use the current version of the libraries(https://adafru.it/ENC).

©Adafruit Industries Page 57 of 124

However, if for some reason you cannot update, links to the previous bundles are

available in the FAQ(https://adafru.it/FwY).

Bootloader (boardnameBOOT) Drive Not Present

You may have a different board.

Only Adafruit Express boards and the SAMD21 non-Express boards ship with the UF2

bootloader (https://adafru.it/zbX)installed. The Feather M0 Basic, Feather M0

Adalogger, and similar boards use a regular Arduino-compatible bootloader, which

does not show a boardnameBOOT drive.

MakeCode

If you are running a MakeCode(https://adafru.it/zbY) program on Circuit Playground

Express, press the reset button just onceto get the CPLAYBOOT drive to show up.

Pressing it twice will not work.

MacOS

DriveDx and its accompanything SAT SMART Driver can interfere with seeing the

BOOT drive. See this forum post(https://adafru.it/sTc) for how to fix the problem.

Windows 10

Did you install the Adafruit Windows Drivers package by mistake, or did you upgrade

to Windows 10 with the driver package installed? You don't need to install this

package on Windows 10 for most Adafruit boards. The old version (v1.5) can interfere

with recognizing your device. Go to Settings -> Apps and uninstall all the "Adafruit"

driver programs.

Windows 7 or 8.1

To use a CircuitPython-compatible board with Windows 7 or 8.1, you must install a

driver. Installation instructions are available here(https://adafru.it/VuB).

It is recommended(https://adafru.it/Amd) that you upgrade to Windows 10 if possible;

an upgrade is probably still free for you. Check here(https://adafru.it/Amd).

©Adafruit Industries Page 58 of 124

The Windows Drivers installer was last updated in November 2020 (v2.5.0.0) .

Windows 7 drivers for CircuitPython boards released since then, including

RP2040 boards, are not yet available. The boards work fine on Windows 10. A

new release of the drivers is in process.

You should now be done! Test by unplugging and replugging the board. You should

see the CIRCUITPY drive, and when you double-click the reset button (single click on

Circuit Playground Express running MakeCode), you should see the appropriateboar

dnameBOOT drive.

Let us know in the Adafruit support forums(https://adafru.it/jIf) or on the Adafruit

Discord() if this does not work for you!

Windows Explorer Locks Up When Accessing boardnameBOOT Drive

On Windows, several third-party programs that can cause issues. The symptom is that

you try to access the boardnameBOOTdrive, and Windows or Windows Explorer

seems to lock up. These programs are known to cause trouble:

AIDA64: to fix, stop the program. This problem has been reported to AIDA64.

•

They acquired hardware to test, and released a beta version that fixes the

problem. This may have been incorporated into the latest release. Please let us

know in the forums if you test this.

Hard Disk Sentinel

•

Kaspersky anti-virus: To fix, you may need to disable Kaspersky completely.

•

Disabling some aspects of Kaspersky does not always solve the problem. This

problem has been reported to Kaspersky.

ESET NOD32 anti-virus: There have been problems with at least version

•

9.0.386.0, solved by uninstallation.

Copying UF2 to boardnameBOOT Drive Hangs at 0% Copied

On Windows, a Western DIgital (WD) utility that comes with their external USB drives

can interfere with copying UF2 files to the boardnameBOOT drive. Uninstall that utility

to fix the problem.

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CIRCUITPY Drive Does Not Appear

Kaspersky anti-virus can block the appearance of the CIRCUITPY drive. There has not

yet been settings change discovered that prevents this. Complete uninstallation of

Kaspersky fixes the problem.

Norton anti-virus can interfere with CIRCUITPY. A user has reported this problem on

Windows 7. The user turned off both Smart Firewall and Auto Protect, and CIRCUITPY

then appeared.

Device Errors or Problems on Windows

Windows can become confused about USB device installations. This is particularly

true of Windows 7 and 8.1. It is recommended(https://adafru.it/Amd) that you upgrade

to Windows 10 if possible; an upgrade is probably still free for you: see this link(https

://adafru.it/V2a).

If not, try cleaning up your USB devices. Use Uwe Sieber's Device Cleanup Tool(http

s://adafru.it/RWd). Download and unzip the tool. Unplug all the boards and other USB

devices you want to clean up. Run the tool as Administrator. You will see a listing like

this, probably with many more devices. It is listing all the USB devices that are not

currently attached.

Select all the devices you want to remove, and then press Delete. It is usually safe

just to select everything. Any device that is removed will get a fresh install when you

plug it in. Using the Device Cleanup Tool also discards all the COM port assignments

for the unplugged boards. If you have used many Arduino and CircuitPython boards,

©Adafruit Industries Page 60 of 124

you have probably seen higher and higher COM port numbers used, seemingly

without end. This will fix that problem.

Serial Console in Mu Not Displaying Anything

There are times when the serial console will accurately not display anything, such as,

when no code is currently running, or when code with no serial output is already

running before you open the console. However, if you find yourself in a situation

where you feel it should be displaying something like an error, consider the following.

Depending on the size of your screen or Mu window, when you open the serial

console, the serial console panel may be very small. This can be a problem. A basic

CircuitPython error takes 10 lines to display!

Auto-reload is on. Simply save files over USB to run them or enter REPL to disable.
code.py output:
Traceback (most recent call last):
File "code.py", line 7
SyntaxError: invalid syntax

Press any key to enter the REPL. Use CTRL-D to reload.

More complex errors take even more lines!

Therefore, if your serial console panel is five lines tall or less, you may only see blank
lines or blank lines followed by Press any key to enter the REPL. Use CTRL-D

to reload. . If this is the case, you need to either mouse over the top of the panel to

utilise the option to resize the serial panel, or use the scrollbar on the right side to

scroll up and find your message.

This applies to any kind of serial output whether it be error messages or print

statements. So before you start trying to debug your problem on the hardware side,

be sure to check that you haven't simply missed the serial messages due to serial

output panel height.

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code.py Restarts Constantly

CircuitPython will restart code.py if you or your computer writes to something on the

CIRCUITPY drive. This feature is called auto-reload, and lets you test a change to your

program immediately.

Some utility programs, such as backup, anti-virus, or disk-checking apps, will write to

the CIRCUITPY as part of their operation. Sometimes they do this very frequently,

causing constant restarts.

Acronis True Image and related Acronis programs on Windows are known to cause

this problem. It is possible to prevent this by disabling the "(https://adafru.it/XDZ)Acr

onis Managed Machine Service Mini"(https://adafru.it/XDZ).

If you cannot stop whatever is causing the writes, you can disable auto-reload by

putting this code in boot.py or code.py:

import supervisor

supervisor.disable_autoreload()

CircuitPython RGB Status Light

Nearly all CircuitPython-capable boards have a single NeoPixel or DotStar RGB LED

on the board that indicates the status of CircuitPython. A few boards designed before

CircuitPython existed, such as the Feather M0 Basic, do not.

Circuit Playground Express and Circuit Playground Bluefruit have multiple RGB LEDs,

but do NOT have a status LED. The LEDs are all green when in the bootloader. In

versions before 7.0.0, they do NOT indicate any status while running CircuitPython.

CircuitPython 7.0.0 and Later

The status LED blinks were changed in CircuitPython 7.0.0 in order to save battery

power and simplify the blinks. These blink patterns will occur on single color LEDs

when the board does not have any RGB LEDs. Speed and blink count also vary for

this reason.

©Adafruit Industries Page 62 of 124

On start up, the LED will blink YELLOW multiple times for 1 second. Pressing reset

during this time will restart the board and then enter safe mode. On Bluetooth

capable boards, after the yellow blinks, there will be a set of faster blue blinks.

Pressing reset during the BLUE blinks will clear Bluetooth information and start the

device in discoverable mode, so it can be used with a BLE code editor.

Once started, CircuitPython will blink a pattern every 5 seconds when no user code is

running to indicate why the code stopped:

1 GREEN blink: Code finished without error.

•

2 RED blinks:Code ended due to an exception. Check the serial console for

•

details.

3 YELLOW blinks:CircuitPython is in safe mode. No user code was run. Check

•

the serial console for safe mode reason.

When in the REPL, CircuitPython will set the status LED to WHITE. You can change the

LED color from the REPL. The status indicator will not persist on non-NeoPixel or

DotStar LEDs.

CircuitPython 6.3.0 and earlier

Here's what the colors and blinking mean:

steady GREEN: code.py (or code.txt, main.py, or main.txt) is running

•

pulsing GREEN: code.py (etc.) has finished or does not exist

•

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steady YELLOW at start up: (4.0.0-alpha.5 and newer) CircuitPython is waiting for

•

a reset to indicate that it should start in safe mode

pulsing YELLOW: Circuit Python is in safe mode: it crashed and restarted

•

steady WHITE: REPL is running

•

steady BLUE: boot.py is running

•

Colors with multiple flashes following indicate a Pythonexception and then indicate

the line number of the error. The color of the first flash indicates the type of error:

GREEN:IndentationError

•

CYAN:SyntaxError

•

WHITE: NameError

•

ORANGE: OSError

•

PURPLE: ValueError

•

YELLOW: other error

•

These are followed by flashes indicating the line number, including place value. WHIT

E flashes are thousands' place, BLUE are hundreds' place, YELLOW are tens' place,

and CYAN are one's place. So for example, an error on line 32 would flash YELLOW

three times and then CYAN two times. Zeroes are indicated by an extra-long dark gap.

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Serial console showing ValueError:

Incompatible .mpy file

This error occurs when importing a module that is stored as a .mpy binary file that

was generated by a different version of CircuitPython than the one its being loaded

into. In particular, the mpy binary format changed between CircuitPython versions 6.x

and 7.x, 2.x and 3.x, and 1.x and 2.x.

So, for instance, if you upgraded to CircuitPython 7.x from 6.x you’ll need to download
a newer version of the library that triggered the error on import . All libraries are

available in the Adafruit bundle(https://adafru.it/y8E).

CIRCUITPY Drive Issues

You may find that you can no longer save files to your CIRCUITPY drive. You may find

that your CIRCUITPY stops showing up in your file explorer, or shows up as NO_NAM

E. These are indicators that your filesystem has issues. When the CIRCUITPY disk is

not safely ejected before being reset by the button or being disconnected from USB,

it may corrupt the flash drive. It can happen on Windows, Mac or Linux, though it is

more common on Windows.

Be aware, if you have used Arduino to program your board, CircuitPython is no longer

able to provide the USB services. You will need to reload CircuitPython to resolve this

situation.

The easiest first step is to reload CircuitPython. Double-tap reset on the board so you

get a boardnameBOOT drive rather than a CIRCUITPY drive, and copy the latest

version of CircuitPython (.uf2) back to the board. This may restore CIRCUITPY

functionality.

If reloading CircuitPython does not resolve your issue, the next step is to try putting

the board into safe mode.

Safe Mode

Whether you've run into a situation where you can no longer edit your code.py on

your CIRCUITPY drive, your board has gotten into a state where CIRCUITPY is read-

only, or you have turned off the CIRCUITPY drive altogether, safe mode can help.

©Adafruit Industries Page 65 of 124

Safe mode in CircuitPython does not run any user code on startup, and disables auto-

reload. This means a few things. First, safe mode bypasses any code in boot.py

(where you can set CIRCUITPY read-only or turn it off completely). Second, it does not

run the code in code.py. And finally, it does not automatically soft-reload when data is

written to the CIRCUITPY drive.

Therefore, whatever you may have done to put your board in a non-interactive state,

safe mode gives you the opportunity to correct it without losing all of the data on the

CIRCUITPY drive.

Entering Safe Mode in CircuitPython 7.x

To enter safe mode when using CircuitPython 7.x, plug in your board or hit reset

(highlighted in red above). Immediately after the board starts up or resets, it waits

1000ms. On some boards, the onboard status LED will blink yellow during that time. If

you press reset during that 1000ms, the board will start up in safe mode. It can be

difficult to react to the yellow LED, so you may want to think of it simply as a "slow"

double click of the reset button. (Remember, a fast double click of reset enters the

bootloader.)

Entering Safe Mode in CircuitPython 6.x

To enter safe mode when using CircuitPython 6.x, plug in your board or hit reset

(highlighted in red above). Immediately after the board starts up or resets, it waits

700ms. On some boards, the onboard status LED (highlighted in green above) will

turn solid yellow during this time. If you press reset during that 700ms, the board will

start up in safe mode. It can be difficult to react to the yellow LED, so you may want to

think of it simply as a slow double click of the reset button. (Remember, a fast double

click of reset enters the bootloader.)

In Safe Mode

Once you've entered safe mode successfully in CircuitPython 6.x, the LED will pulse

yellow.

If you successfully enter safe mode on CircuitPython 7.x, the LED will intermittently

blink yellow three times.

If you connect to the serial console, you'll find the following message.

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Auto-reload is off.
Running in safe mode! Not running saved code.

CircuitPython is in safe mode because you pressed the reset button during boot.
Press again to exit safe mode.

Press any key to enter the REPL. Use CTRL-D to reload.

You can now edit the contents of the CIRCUITPY drive. Remember, your code will not

run until you press the reset button, or unplug and plug in your board, to get out of

safe mode.

At this point, you'll want to remove any user code incode.py and, if present, the boot.

py file from CIRCUITPY. Once removed, tap the reset button, or unplug and plug in

your board, to restart CircuitPython. This will restart the board and may resolve your

drive issues. If resolved, you can begin coding again as usual.

If safe mode does not resolve your issue, the board must be completely erased and

CircuitPython must be reloaded onto the board.

You WILL lose everything on the board when you complete the following steps. If

possible, make a copy of your code before continuing.

To erase CIRCUITPY: storage.erase_filesystem()

CircuitPython includes a built-in function to erase and reformat the filesystem. If you

have a version of CircuitPython older than 2.3.0 on your board, you can update to the

newest version(https://adafru.it/Amd) to do this.

Connect to the CircuitPython REPL(https://adafru.it/Bec)using Mu or a terminal

1.

program.

Type the following into the REPL:

2.

>>> import storage
>>> storage.erase_filesystem()

CIRCUITPY will be erased and reformatted, and your board will restart. That's it!

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Erase CIRCUITPY Without Access to the REPL

If you can't access the REPL, or you're running a version of CircuitPython previous to

2.3.0 and you don't want to upgrade, there are options available for some specific

boards.

The options listed below are considered to be the "old way" of erasing your board.

The method shown above using the REPL is highly recommended as the best method

for erasing your board.

If at all possible, it is recommended to use the REPL to erase your CIRCUITPY

drive. The REPL method is explained above.

For the specific boards listed below:

If the board you are trying to erase is listed below, follow the steps to use the file to

erase your board.

 1. Download the correct erase file:

Circuit Playground Express

https://adafru.it/AdI

Feather M0 Express

https://adafru.it/AdJ

Feather M4 Express

https://adafru.it/EVK

Metro M0 Express

https://adafru.it/AdK

Metro M4 Express QSPI Eraser

https://adafru.it/EoM

Trellis M4 Express (QSPI)

https://adafru.it/DjD

©Adafruit Industries Page 68 of 124

Grand Central M4 Express (QSPI)

https://adafru.it/DBA

PyPortal M4 Express (QSPI)

https://adafru.it/Eca

Circuit Playground Bluefruit (QSPI)

https://adafru.it/Gnc

Monster M4SK (QSPI)

https://adafru.it/GAN

PyBadge/PyGamer QSPI Eraser.UF2

https://adafru.it/GAO

CLUE_Flash_Erase.UF2

https://adafru.it/Jat

Matrix_Portal_M4_(QSPI).UF2

https://adafru.it/Q5B

 2. Double-click the reset button on the board to bring up the boardnameBOOT

drive.

 3. Drag the erase .uf2 file to theboardnameBOOT drive.

 4. The status LED will turn yellow or blue, indicating the erase has started.

 5. After approximately 15 seconds, the status LED will light up green. On the

NeoTrellis M4 this is the first NeoPixel on the grid

 6. Double-click the reset button on the board to bring up theboardnameBOOTd

rive.

 7. Drag the appropriate latest release of CircuitPython(https://adafru.it/Em8) .uf2

file to theboardnameBOOTdrive.

It should reboot automatically and you should see CIRCUITPY in your file explorer

again.

If the LED flashes red during step 5, it means the erase has failed. Repeat the steps

starting with 2.

©Adafruit Industries Page 69 of 124

If you haven't already downloaded the latest release of CircuitPython for your board,

check out the installation page(https://adafru.it/Amd). You'll also need to load your

code and reinstall your libraries!

For SAMD21 non-Express boards that have a UF2 bootloader:

Any SAMD21-based microcontroller that does not have external flash available is

considered a SAMD21 non-Express board. Non-Express boards that have a UF2

bootloader include Trinket M0, GEMMA M0, QT Py M0, and the SAMD21-based

Trinkey boards.

If you are trying to erase a SAMD21 non-Express board, follow these steps to erase

your board.

 1. Download the erase file:

SAMD21 non-Express Boards

https://adafru.it/VB-

 2. Double-click the reset button on the board to bring up the boardnameBOOT

drive.

 3. Drag the erase .uf2 file to the boardnameBOOT drive.

 4. The boot LED will start flashing again, and the boardnameBOOT drive will

reappear.

 5. Drag the appropriate latest release CircuitPython(https://adafru.it/Em8) .uf2

file to the boardnameBOOT drive.

It should reboot automatically and you should see CIRCUITPY in your file explorer

again.

If you haven't already downloaded the latest release of CircuitPython for your board,

check out the installation page(https://adafru.it/Amd) YYou'll also need to load your

code and reinstall your libraries!

For SAMD21 non-Express boards that do not have a UF2 bootloader:

Any SAMD21-based microcontroller that does not have external flash available is

considered a SAMD21 non-Express board. Non-Express boards that do not have a

©Adafruit Industries Page 70 of 124

UF2 bootloader include the Feather M0 Basic Proto, Feather Adalogger, or the

Arduino Zero.

If you are trying to erase a non-Express board that does not have a UF2 bootloader, f

ollow these directions toreload CircuitPython using bossac (https://adafru.it/Bed),

which will erase and re-create CIRCUITPY.

Running Out of File Space on SAMD21 Non­Express Boards

Any SAMD21-based microcontroller that does not have external flash available is

considered a SAMD21 non-Express board. This includes boards like the Trinket M0,

GEMMA M0, QT Py M0, and the SAMD21-based Trinkey boards.

The file system on the board is very tiny. (Smaller than an ancient floppy disk.) So, its

likely you'll run out of space but don't panic! There are a number of ways to free up

space.

Delete something!

The simplest way of freeing up space is to delete files from the drive. Perhaps there

are libraries in the lib folder that you aren't using anymore or test code that isn't in

use. Don't delete the lib folder completely, though, just remove what you don't need.

The board ships with the Windows 7 serial driver too! Feel free to delete that if you

don't need it or have already installed it. It's ~12KiB or so.

Use tabs

One unique feature of Python is that the indentation of code matters. Usually the

recommendation is to indent code with four spaces for every indent. In general, that

©Adafruit Industries Page 71 of 124

is recommended too. However, one trick to storing more human-readable code is to

use a single tab character for indentation. This approach uses 1/4 of the space for

indentation and can be significant when you're counting bytes.

On MacOS?

MacOS loves to generate hidden files. Luckily you can disable some of the extra

hidden files that macOS adds by running a few commands to disable search indexing

and create zero byte placeholders. Follow the steps below to maximize the amount of

space available on macOS.

Prevent & Remove MacOS Hidden Files

First find the volume name for your board. With the board plugged in run this

command in a terminal to list all the volumes:

ls -l /Volumes

Look for a volume with a name likeCIRCUITPY(the default for CircuitPython). The full

path to the volume is the/Volumes/CIRCUITPYpath.

Now follow thesteps from this question(https://adafru.it/u1c)to run these terminal

commands that stop hidden files from being created on the board:

mdutil -i off /Volumes/CIRCUITPY
cd /Volumes/CIRCUITPY
rm -rf .{,_.}{fseventsd,Spotlight-V*,Trashes}
mkdir .fseventsd
touch .fseventsd/no_log .metadata_never_index .Trashes
cd -

Replace/Volumes/CIRCUITPYin the commands above with the full path to your

board's volume if it's different. At this point all the hidden files should be cleared from

the board and some hidden files will be prevented from being created.

Alternatively, with CircuitPython 4.x and above, the special files and folders

mentioned above will be created automatically if you erase and reformat the

filesystem. WARNING: Save your files first! Do this in the REPL:

>>> import storage
>>> storage.erase_filesystem()

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However there are still some cases where hidden files will be created by MacOS. In

particular if you copy a file that was downloaded from the internet it will have special

metadata that MacOS stores as a hidden file. Luckily you can run a copy command

from the terminal to copy files without this hidden metadata file. See the steps below.

Copy Files on MacOS Without Creating Hidden Files

Once you've disabled and removed hidden files with the above commands on macOS

you need to be careful to copy files to the board with a special command that

prevents future hidden files from being created. Unfortunately you cannotuse drag

and drop copy in Finder because it will still create these hidden extended attribute

files in some cases (for files downloaded from the internet, like Adafruit's modules).

To copy a file or folder use the-Xoption for thecpcommand in a terminal. For

example to copy a file_name.mpy file to the board use a command like:

cp -X file_name.mpy /Volumes/CIRCUITPY

(Replace file_name.mpy with the name of the file you want to copy.)

Or to copy a folder and all of the files and folders contained within, use a command

like:

cp -rX folder_to_copy /Volumes/CIRCUITPY

If you are copying to the lib folder, or another folder, make sure it exists before

copying.

# if lib does not exist, you'll create a file named lib !

cp -X file_name.mpy /Volumes/CIRCUITPY/lib

# This is safer, and will complain if a lib folder does not exist.

cp -X file_name.mpy /Volumes/CIRCUITPY/lib/

Other MacOS Space-Saving Tips

If you'd like to see the amount of space used on the drive and manually delete hidden
files here's how to do so. First, move into the Volumes/ directory with cd /Volumes/ ,
and then list the amount of space used on the CIRCUITPY drive with the df

command.

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That's not very much space left! The next step is to show a list of the files currently on
the CIRCUITPY drive, including the hidden files, using the ls command. You cannot

use Finder to do this, you must do it via command line!

There are a few of the hidden files that MacOS loves to generate, all of which begin
with a ._ before the file name. Remove the ._ files using the rm command. You can
remove them all once by running rm CIRCUITPY/._* . The * acts as a wildcard to

apply the command to everything that begins with ._ at the same time.

Finally, you can run df again to see the current space used.

Nice! You have 12Ki more than before! This space can now be used for libraries and

code!

Device Locked Up or Boot Looping

In rare cases, it may happen that something in your code.py or boot.py files causes

the device to get locked up, or even go into a boot loop. A boot loop occurs when the

board reboots repeatedly and never fully loads. These are not caused by your

everyday Python exceptions, typically it's the result of a deeper problem within

CircuitPython. In this situation, it can be difficult to recover your device if CIRCUITPY

is not allowing you to modify the code.py or boot.py files. Safe mode is one recovery

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option. When the device boots up in safe mode it will not run the code.py or boot.py

scripts, but will still connect the CIRCUITPY drive so that you can remove or modify

those files as needed.

The method used to manually enter safe mode can be different for different devices.

It is also very similar to the method used for getting into bootloader mode, which is a

different thing. So it can take a few tries to get the timing right. If you end up in

bootloader mode, no problem, you can try again without needing to do anything else.

For most devices:

Press the reset button, and then when the RGB status LED blinks yellow, press the

reset button again. Since your reaction time may not be that fast, try a "slow" double

click, to catch the yellow LED on the second click.

For ESP32-S2 based devices:

Press and release the reset button, then press and release the boot button about 3/4

of a second later.

Refer to the diagrams above for boot sequence details.

"Uninstalling" CircuitPython

A lot of our boards can be used with multiple programming languages. For example,

the Circuit Playground Express can be used with MakeCode, Code.org CS

Discoveries, CircuitPython and Arduino.

Maybe you tried CircuitPython and want to go back to MakeCode or Arduino? Not a

problem. You can always remove or reinstall CircuitPython whenever you want! Heck,

you can change your mind every day!

There is nothing to uninstall. CircuitPython is "just another program" that is loaded

onto your board. You simply load another program (Arduino or MakeCode) and it will

overwrite CircuitPython.

Backup Your Code

Before replacing CircuitPython, don't forget to make a backup of the code you have

on the CIRCUITPY drive. That means your code.py any other files, the lib folder etc.

You may lose these files when you remove CircuitPython, so backups are key! Just

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drag the files to a folder on your laptop or desktop computer like you would with any

USB drive.

Moving Circuit Playground Express to MakeCode

On the Circuit Playground Express (this currently does NOT apply to Circuit

Playground Bluefruit), if you want to go back to using MakeCode, it's really easy. Visit

makecode.adafruit.com(https://adafru.it/wpC) and find the program you want to

upload. Click Download to download the .uf2 file that is generated by MakeCode.

Now double-click your CircuitPython board until you see the onboard LED(s) turn

green and the ...BOOT directory shows up.

Then find the downloaded MakeCode .uf2 file and drag it to the CPLAYBOOT drive.

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Your MakeCode is now running and CircuitPython has been removed. Going forward

you only have to single click the reset button to get to CPLAYBOOT. This is an

idiosyncrasy of MakeCode.

Moving to Arduino

If you want to use Arduino instead, you just use the Arduino IDE to load an Arduino

program. Here's an example of uploading a simple "Blink" Arduino program, but you

don't have to use this particular program.

Start by plugging in your board, and double-clicking reset until you get the green

onboard LED(s).

Within Arduino IDE, select the matching board, say Circuit Playground Express.

Select the correct matching Port:

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Create a new simple Blink sketch example:

// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin 13 as an output.
pinMode(13, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
digitalWrite(13, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(13, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second
}

Make sure the LED(s) are still green, then click Upload to upload Blink. Once it has

uploaded successfully, the serial Port will change so re-select the new Port!

Once Blink is uploaded you should no longer need to double-click to enter

bootloader mode. Arduino will automatically reset when you upload.

Welcome to the Community!

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CircuitPython is a programming language that's super simple to get started with and

great for learning. It runs on microcontrollers and works out of the box. You can plug it

in and get started with any text editor. The best part? CircuitPython comes with an

amazing, supportive community.

Everyone is welcome! CircuitPython is Open Source. This means it's available for

anyone to use, edit, copy and improve upon. This also means CircuitPython becomes

better because of you being a part of it. Whether this is your first microcontroller

board or you're a seasoned software engineer, you have something important to offer

the Adafruit CircuitPython community. This page highlights some of the many ways

you can be a part of it!

Adafruit Discord

The Adafruit Discord server is the best place to start. Discord is where the community

comes together to volunteer and provide live support of all kinds. From general

discussion to detailed problem solving, and everything in between, Discord is a digital

maker space with makers from around the world.

There are many different channels so you can choose the one best suited to your

needs. Each channel is shown on Discord as "#channelname". There's the #help-with-

projects channel for assistance with your current project or help coming up with ideas

for your next one. There's the #show-and-tell channel for showing off your newest

creation. Don't be afraid to ask a question in any channel! If you're unsure, #general is

a great place to start. If another channel is more likely to provide you with a better

answer, someone will guide you.

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The help with CircuitPython channel is where to go with your CircuitPython questions.

#help-with-circuitpython is there for new users and developers alike so feel free to

ask a question or post a comment! Everyone of any experience level is welcome to

join in on the conversation. Your contributions are important! The #circuitpython-dev

channel is available for development discussions as well.

The easiest way to contribute to the community is to assist others on Discord.

Supporting others doesn't always mean answering questions. Join in celebrating

successes! Celebrate your mistakes! Sometimes just hearing that someone else has

gone through a similar struggle can be enough to keep a maker moving forward.

The Adafruit Discord is the 24x7x365 hackerspace that you can bring your

granddaughter to.

Visit https://adafru.it/discord ()to sign up for Discord. Everyone is looking forward to

meeting you!

CircuitPython.org

Beyond the Adafruit Learn System, which you are viewing right now, the best place to

find information about CircuitPython is circuitpython.org(https://adafru.it/KJD).

Everything you need to get started with your new microcontroller and beyond is

available. You can do things like download CircuitPython for your microcontroller(htt

ps://adafru.it/Em8) or download the latest CircuitPython Library bundle(https://

adafru.it/ENC), or check out which single board computers support Blinka(https://

adafru.it/EA8). You can also get to various other CircuitPython related things like

Awesome CircuitPython or the Python for Microcontrollers newsletter. This is all

incredibly useful, but it isn't necessarily community related. So why is it included

here? The Contributing page(https://adafru.it/VD7).

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CircuitPython itself is written in C. However, all of the Adafruit CircuitPython libraries

are written in Python. If you're interested in contributing to CircuitPython on the

Python side of things, check out circuitpython.org/contributing(https://adafru.it/VD7).

You'll find information pertaining to every Adafruit CircuitPython library GitHub

repository, giving you the opportunity to join the community by finding a contributing

option that works for you.

Note the date on the page next to Current Status for:

If you submit any contributions to the libraries, and do not see them reflected on the

Contributing page, it could be that the job that checks for new updates hasn't yet run

for today. Simply check back tomorrow!

Now, a look at the different options.

Pull Requests

The first tab you'll find is a list of open pull requests.

GitHub pull requests, or PRs, are opened when folks have added something to an

Adafruit CircuitPython library GitHub repo, and are asking for Adafruit to add, or

merge, their changes into the main library code. For PRs to be merged, they must first

be reviewed. Reviewing is a great way to contribute! Take a look at the list of open

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pull requests, and pick one that interests you. If you have the hardware, you can test

code changes. If you don't, you can still check the code updates for syntax. In the

case of documentation updates, you can verify the information, or check it for spelling

and grammar. Once you've checked out the update, you can leave a comment letting

us know that you took a look. Once you've done that for a while, and you're more

comfortable with it, you can consider joining the CircuitPythonLibrarians review team.

The more reviewers we have, the more authors we can support. Reviewing is a crucial

part of an open source ecosystem, CircuitPython included.

Open Issues

The second tab you'll find is a list of open issues.

GitHub issues are filed for a number of reasons, including when there is a bug in the

library or example code, or when someone wants to make a feature request. Issues

are a great way to find an opportunity to contribute directly to the libraries by

updating code or documentation. If you're interested in contributing code or

documentation, take a look at the open issues and find one that interests you.

If you're not sure where to start, you can search the issues by label. Labels are

applied to issues to make the goal easier to identify at a first glance, or to indicate the

difficulty level of the issue. Click on the dropdown next to "Sort by issue labels" to see

the list of available labels, and click on one to choose it.

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If you're new to everything, new to contributing to open source, or new to

contributing to the CircuitPython project, you can choose "Good first issue". Issues

with that label are well defined, with a finite scope, and are intended to be easy for

someone new to figure out.

If you're looking for something a little more complicated, consider "Bug" or

"Enhancement". The Bug label is applied to issues that pertain to problems or failures

found in the library. The Enhancement label is applied to feature requests.

Don't let the process intimidate you. If you're new to Git and GitHub, there is a guide(

https://adafru.it/Dkh) to walk you through the entire process. As well, there are always

folks available on Discord() to answer questions.

Library Infrastructure Issues

The third tab you'll find is a list of library infrastructure issues.

This section is generated by a script that runs checks on the libraries, and then

reports back where there may be issues. It is made up of a list of subsections each

containing links to the repositories that are experiencing that particular issue. This

page is available mostly for internal use, but you may find some opportunities to

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contribute on this page. If there's an issue listed that sounds like something you could

help with, mention it on Discord, or file an issue on GitHub indicating you're working

to resolve that issue. Others can reply either way to let you know what the scope of it

might be, and help you resolve it if necessary.

CircuitPython Localization

The fourth tab you'll find is the CircuitPython Localization tab.

If you speak another language, you can help translate CircuitPython! The translations

apply to informational and error messages that are within the CircuitPython core. It

means that folks who do not speak English have the opportunity to have these

messages shown to them in their own language when using CircuitPython. This is

incredibly important to provide the best experience possible for all users.

CircuitPython uses Weblate to translate, which makes it much simpler to contribute

translations. You will still need to know some CircuitPython-specific practices and a

few basics about coding strings, but as with any CircuitPython contributions, folks are

there to help.

Regardless of your skill level, or how you want to contribute to the CircuitPython

project, there is an opportunity available. The Contributing page(https://adafru.it/VD7)

is an excellent place to start!

Adafruit GitHub

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Whether you're just beginning or are life-long programmer who would like to

contribute, there are ways for everyone to be a part of the CircuitPython project. The

CircuitPython core is written in C. The libraries are written in Python. GitHub is the

best source of ways to contribute to the CircuitPython core(https://adafru.it/tB7), and

the CircuitPython libraries(https://adafru.it/VFv). If you need an account, visit https://

github.com/(https://adafru.it/d6C)and sign up.

If you're new to GitHub or programming in general, there are great opportunities for

you. For the CircuitPython core, head over to the CircuitPython repository on GitHub,

click on "Issues(https://adafru.it/tBb)", and you'll find a list that includes issues labeled

"good first issue(https://adafru.it/Bef)". For the libraries, head over to the Contributing

page Issues list(https://adafru.it/VFv), and use the drop down menu to search for "go

od first issue(https://adafru.it/VFw)". These issues are things that have been identified

as something that someone with any level of experience can help with. These issues

include options like updating documentation, providing feedback, and fixing simple

bugs. If you need help getting started with GitHub, there is an excellent guide on Con

tributing to CircuitPython with Git and GitHub(https://adafru.it/Dkh).

Already experienced and looking for a challenge? Checkout the rest of either issues

list and you'll find plenty of ways to contribute. You'll find all sorts of things, from new

driver requests, to library bugs, to core module updates. There's plenty of

opportunities for everyone at any level!

When working with or using CircuitPython or the CircuitPython libraries, you may find

problems. If you find a bug, that's great! The team loves bugs! Posting a detailed issue

to GitHub is an invaluable way to contribute to improving CircuitPython. For

CircuitPython itself, file an issue here(https://adafru.it/tBb). For the libraries, file an

issue on the specific library repository on GitHub. Be sure to include the steps to

replicate the issue as well as any other information you think is relevant. The more

detail, the better!

Testing new software is easy and incredibly helpful. Simply load the newest version of

CircuitPython or a library onto your CircuitPython hardware, and use it. Let us know

about any problems you find by posting a new issue to GitHub. Software testing on

both stable and unstable releases is a very important part of contributing

CircuitPython. The developers can't possibly find all the problems themselves! They

need your help to make CircuitPython even better.

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On GitHub, you can submit feature requests, provide feedback, report problems and

much more. If you have questions, remember that Discord and the Forums are both

there for help!

Adafruit Forums

The Adafruit Forums(https://adafru.it/jIf ) are the perfect place for support. Adafruit

has wonderful paid support folks to answer any questions you may have. Whether

your hardware is giving you issues or your code doesn't seem to be working, the

forums are always there for you to ask. You need an Adafruit account to post to the

forums. You can use the same account you use to order from Adafruit.

While Discord may provide you with quicker responses than the forums, the forums

are a more reliable source of information. If you want to be certain you're getting an

Adafruit-supported answer, the forums are the best place to be.

There are forum categories that cover all kinds of topics, including everything

Adafruit. The Adafruit CircuitPython(https://adafru.it/xXA)category under "Supported

Products & Projects" is the best place to post your CircuitPython questions.

Be sure to include the steps you took to get to where you are. If it involves wiring,

post a picture! If your code is giving you trouble, include your code in your post!

These are great ways to make sure that there's enough information to help you with

your issue.

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You might think you're just getting started, but you definitely know something that

someone else doesn't. The great thing about the forums is that you can help others

too! Everyone is welcome and encouraged to provide constructive feedback to any of

the posted questions. This is an excellent way to contribute to the community and

share your knowledge!

Read the Docs

Read the Docs(https://adafru.it/Beg) is a an excellent resource for a more detailed

look at the CircuitPython core and the CircuitPython libraries. This is where you'll find

things like API documentation and example code. For an in depth look at viewing and

understanding Read the Docs, check out the CircuitPython Documentation(https://

adafru.it/VFx) page!

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CircuitPython Essentials

You've been introduced to CircuitPython, and worked through getting everything set

up. What's next? CircuitPython Essentials!

There are a number of core modules built into CircuitPython, which can be used along

side the many CircuitPython libraries available. The following pages demonstrate

some of these modules. Each page presents a different concept including a code

example with an explanation. All of the examples are designed to work with your

microcontroller board.

Time to get started learning the CircuitPython essentials!

Blink

In learning any programming language, you often begin with some sort of Hello,

World! program. In CircuitPython, Hello, World! is blinking an LED. Blink is one of the

simplest programs in CircuitPython. It involves three built-in modules, two lines of set

up, and a short loop. Despite its simplicity, it shows you many of the basic concepts

needed for most CircuitPython programs, and provides a solid basis for more complex

projects. Time to get blinky!

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LED Location

The red LED is located on the top edge

of the back of the board, to the left of the

USB connector.

Blinking an LED

Save the following as code.py on your CIRCUITPY drive.

# SPDX-FileCopyrightText: 2021 Kattni Rembor for Adafruit Industries
# SPDX-License-Identifier: Unlicense

"""CircuitPython Blink Example - the CircuitPython 'Hello, World!'"""

import time
import board
import digitalio

led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

while True:

led.value = True
time.sleep(0.5)
led.value = False
time.sleep(0.5)

The built-in LED begins blinking!

Note that the code is a little less "Pythonic" than it could be. It could also be written as

led.value = not led.value with a single time.sleep(0.5) . That way is more

difficult to understand if you're new to programming, so the example is a bit longer

than it needed to be to make it easier to read.

It's important to understand what is going on in this program.

First you import three modules: time , board and digitalio . This makes these

modules available for use in your code. All three are built-in to CircuitPython, so you

don't need to download anything to get started.

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Next, you set up the LED. To interact with hardware in CircuitPython, your code must

let the board know where to look for the hardware and what to do with it. So, you
create a digitalio.DigitalInOut() object, provide it the LED pin using the boa

rd module, and save it to the variable led . Then, you tell the pin to act as an OUTP
UT .

Finally, you create a while True: loop. This means all the code inside the loop will
repeat indefinitely. Inside the loop, you set led.value = True which powers on the
LED. Then, you use time.sleep(0.5) to tell the code to wait half a second before
moving on to the next line. The next line sets led.value = False which turns the
LED off. Then you use another time.sleep(0.5) to wait half a second before

starting the loop over again.

With only a small update, you can control the blink speed. The blink speed is
controlled by the amount of time you tell the code to wait before moving on using ti

me.sleep() . The example uses 0.5 , which is one half of one second. Try increasing

or decreasing these values to see how the blinking changes.

That's all there is to blinking an LED using CircuitPython!

Digital Input

The CircuitPython digitalio module has many applications. The basic Blink

program sets up the LED as a digital output. You can just as easily set up a digital

input such as a button to control the LED. This example builds on the basic Blink
example, but now includes setup for a button switch. Instead of using the time

module to blink the LED, it uses the status of the button switch to control whether the

LED is turned on or off.

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LED and Button

The red LED (highlighted in red) is

•

located on the top edge of the back

of the board, to the left of the USB

connector.

The button (highlighted in green) is

•

located in the rotary encoder - to

use the button, simply press down

on the rotary encoder.

Controlling the LED with a Button

Save the following as code.py on your CIRCUITPY drive.

"""CircuitPython Digital Input example for MacroPad"""

import board
import digitalio

led = digitalio.DigitalInOut(board.LED)
led.direction = digitalio.Direction.OUTPUT

button = digitalio.DigitalInOut(board.BUTTON)
button.switch_to_input(pull=digitalio.Pull.UP)

while True:

if not button.value:
led.value = True
else:
led.value = False

Now, press the button. The LED lights up! Let go of the button and the LED turns off.

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Note that the code is a little less "Pythonic" than it could be. It could also be written as

led.value = not button.value . That way is more difficult to understand if you're

new to programming, so the example is a bit longer than it needed to be to make it

easier to read.

First you import two modules: board and digitalio . This makes these modules

available for use in your code. Both are built-in to CircuitPython, so you don't need to

download anything to get started.

Next, you set up the LED. To interact with hardware in CircuitPython, your code must

let the board know where to look for the hardware and what to do with it. So, you
create a digitalio.DigitalInOut() object, provide it the LED pin using the boa

rd module, and save it to the variable led . Then, you tell the pin to act as an OUTP
UT .

You include setup for the button as well. It is similar to the LED setup, except the
button is an INPUT , and requires a pull up.

Inside the loop, you check to see if the button is pressed, and if so, turn on the LED.

Otherwise the LED is off.

That's all there is to controlling an LED with a button switch!

Keypad

To use the keypad module, you must be running at least CircuitPython 7.0.0-

alpha.4!

Using the keys on the Adafruit MacroPad in CircuitPython is super simple, thanks to
the keypad module. This module allows you to print the key number, and read key
press and releases. The rotaryio module allows you to read the rotation of the
rotary encoder, and digitalio allows you to read the rotary encoder button switch

presses. All of these modules are built into CircuitPython, meaning to use them, you

do not need to load any separate libraries onto your MacroPad.

However, the following example involves the NeoPixel LEDs, which do require a

separate library - Adafruit CircuitPython NeoPixel.

Save the following to your CIRCUITPY drive as code.py.

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Click the Download Project Bundle button below to download the necessary libraries

and the code.py file in a zip file. Extract the contents of the zip file, find your

CircuitPython version, and copy the matching entire lib folder and code.py file to your

CIRCUITPY drive.

"""Keypad and rotary encoder example for Adafruit MacroPad"""

import board
import digitalio
import rotaryio
import neopixel
import keypad
from rainbowio import colorwheel

key_pins = (board.KEY1, board.KEY2, board.KEY3, board.KEY4, board.KEY5, board.KEY6,
board.KEY7, board.KEY8, board.KEY9, board.KEY10, board.KEY11,
board.KEY12)
keys = keypad.Keys(key_pins, value_when_pressed=False, pull=True)

encoder = rotaryio.IncrementalEncoder(board.ROTA, board.ROTB)
button = digitalio.DigitalInOut(board.BUTTON)
button.switch_to_input(pull=digitalio.Pull.UP)

pixels = neopixel.NeoPixel(board.NEOPIXEL, 12, brightness=0.2)

last_position = None

while True:

if not button.value:
pixels.brightness = 1.0
else:
pixels.brightness = 0.2

position = encoder.position
if last_position is None or position != last_position:
print("Rotary:", position)
last_position = position

color_value = (position * 2) % 255

event = keys.events.get()
if event:
print(event)
if event.pressed:
pixels[event.key_number] = colorwheel(color_value)
else:
pixels[event.key_number] = 0

Now try pressing any of the keys to see a message printed out. The corresponding

NeoPixel will light up. To change the color of the NeoPixel and see a value printed

out, rotate the rotary encoder. To temporarily increase the brightness of the NeoPixel,

press down on the rotary encoder.

Note that the key numbers start at 0, so the printed key numbers are 0-11. The

CircuitPython pin names are KEY1 - KEY12. KEY1 is key number 0, KEY2 is key

number 1, etc, through KEY12 being key number 11.

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MacroPad CircuitPython Library

The Adafruit MacroPad has a number of great features, all of which work great with

CircuitPython. The Adafruit CircuitPython MacroPad(https://adafru.it/U9C) library

wraps all of those features into one place to make it super simple to get started using

CircuitPython with your Adafruit MacroPad.

This section provides a few examples of using the MacroPad CircuitPython library to

read key presses, the rotary encoder values and rotary encoder switch state, and to

send HID and MIDI commands.

The MacroPad library is easy to use. Simply import it, and then create an instance of it

in your code. To do this, you include the following two lines at the beginning of your

program.

from adafruit_macropad import MacroPad

macropad = MacroPad()

Then, you're ready to access all the features of the library using macropad . Each of

the examples will show you how to access different features of the library.

First, you'll want to install the MacroPad library and its dependencies.

MacroPad Library Installation

To use the MacroPad library, you'll need to install it and a few other CircuitPython

libraries on your CIRCUITPY drive.

There are two ways to get the necessary libraries onto your CIRCUITPY drive. You can

click the Download Project Bundle button at the top of each example, open the 7.x

folder within, and copy the code.py file and the lib folder to your CIRCUITPY drive.

Alternatively, you can follow the instructions below.

Download the latest Adafruit CircuitPython Bundle that matches the version of

CircuitPython you're using.

Download the latest CircuitPython

Library Bundle

©Adafruit Industries Page 94 of 124

https://adafru.it/ENC

Extract the zip and navigate to the lib folder found within. Drag the necessary libraries

from the zip lib folder to the lib folder on your CIRCUITPY drive.

At a minimum, the following libraries are required to use the MacroPad CircuitPython

library. Drag the following files and folders to the lib folder on your CIRCUITPY drive:

adafruit_macropad.mpy - A helper library for using the features of the Adafruit

•

MacroPad.

adafruit_debouncer.mpy - A helper library for debouncing pins. Used to provide

•

a debounced instance of the rotary encoder switch.

adafruit_simple_text_display.mpy - A helper library for easily displaying lines of

•

text on a display.

neopixel.mpy - A CircuitPython driver for NeoPixel LEDs.

•

adafruit_display_text/ - A library to display text using displayio . Used for the

•

text display functionality of the MacroPad library that allows you easily display

lines of text on the built-in display.

adafruit_hid/ - CircuitPython USB HID drivers.

•

adafruit_midi/ - A CircuitPython helper for encoding/decoding MIDI packets over

•

a MIDI or UART connection

There is an example included that uses a library that is not required for the MacroPad

library to work, but provides a convenient way to layout text in grid. The following

library is recommended as well:

adafruit_displayio_layout - A library that includes a grid layout helper.

•

MacroPad Basics

The Adafruit MacroPad RP2040 features a 3x4 key pad with NeoPixel LEDs, and a

rotary encoder with push switch. This example reads the key presses, the relative

position of the rotary encoder and the state of the rotary encoder switch, and prints

the information to the serial console.

Update your code.py to the following.

Click the Download Project Bundle button below to download the necessary libraries

and the code.py file in a zip file. Extract the contents of the zip file, open the folder

©Adafruit Industries Page 95 of 124

that matches your CircuitPython version, and copy the entire lib folder and the code.

py file to your CIRCUITPY drive.

# SPDX-FileCopyrightText: Copyright (c) 2021 Kattni Rembor for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense

"""
Simpletest demo for MacroPad. Prints the key pressed, the relative position of the
rotary
encoder, and the state of the rotary encoder switch to the serial console.
"""

import time
from adafruit_macropad import MacroPad

macropad = MacroPad()

while True:

key_event = macropad.keys.events.get()
if key_event and key_event.pressed:
print("Key pressed: {}".format(key_event.key_number))
print("Encoder: {}".format(macropad.encoder))
print("Encoder switch: {}".format(macropad.encoder_switch))
time.sleep(0.4)

Now, connect to the serial console(https://adafru.it/Bec). Try pressing keys, rotating

the rotary encoder, and pressing the rotary encoder switch to see the results printed

out.

To use the MacroPad library, you need to import it and instantiate it with the following

code:

from adafruit_macropad import MacroPad

macropad = MacroPad()

Once, instantiated as macropad , you have access to all the features of the MacroPad
library. To use the features of the library, you include macropad.feature_name in

your code. This example uses the following features:

keys - The keys on the MacroPad. Uses events to track key number and state,

•

e.g. pressed or released. You must fetch the events using keys.events.get()

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and then the events are available for usage in your code. Each event has three
properties: key_number , pressed , and released .

encoder - The rotary encoder relative rotation position. Always begins at 0

•

when the code is run, so the value returned is relative to the initial location.

encoder_switch - The rotary encoder switch. Returns True when pressed.

•

Therefore, to read the rotary encoder, you would include macropad.encoder in your

code.

In this example, you first import time , then the MacroPad library, and instantiate the
library as macropad .

Inside the loop, the first thing you do is setup to look for the key press by creating the

key_event variable and assigning it to macropad.keys.events.get() . Then, you

check to see if there is a key_event (i.e. a key being pressed) and if it is a key being
pressed ( key_event.pressed ). Then, if so, print the key number ( key_event.key_

number ) being pressed to the serial console.

Then, you print to the serial console the relative position of the rotary encoder (with m

acropad.encoder ) and the state of the encoder switch (with macropad.encoder_s
witch ).

Finally, you include a time.sleep(0.4) to print the information every 0.4 seconds to

keep the serial console results readable.

That's all there is to reading the key presses, rotary encoder relative position, and

rotary encoder switch state on the Adafruit MacroPad using the CircuitPython

MacroPad library!

MacroPad Display Text

The Adafruit MacroPad RP2040 features a 3x4 key pad with NeoPixel LEDs, a rotary

encoder with push switch, and a display. This example reads the key presses, the

relative position of the rotary encoder and the state of the rotary encoder switch, and

displays the information on the display.

Update your code.py to the following.

Click the Download Project Bundle button below to download the necessary libraries

and the code.py file in a zip file. Extract the contents of the zip file, open the folder

©Adafruit Industries Page 97 of 124

that matches your CircuitPython version, and copy the entire lib folder and the code.

py file to your CIRCUITPY drive.

# SPDX-FileCopyrightText: Copyright (c) 2021 Kattni Rembor for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense

"""
Simpletest demo for MacroPad. Displays the key pressed, the relative position of
the rotary
encoder, and the state of the rotary encoder switch to the built-in display. Note
that the key
pressed line does not appear until a key is pressed.
"""

from adafruit_macropad import MacroPad

macropad = MacroPad()

text_lines = macropad.display_text(title="MacroPad Info")

while True:

key_event = macropad.keys.events.get()
if key_event and key_event.pressed:
text_lines[0].text = "Key {} pressed!".format(key_event.key_number)
text_lines[1].text = "Rotary encoder {}".format(macropad.encoder)
text_lines[2].text = "Encoder switch: {}".format(macropad.encoder_switch)
text_lines.show()

Now, check out the display!

If you rotate the rotary encoder, the number will change. It doesn't matter where the

rotary encoder is, it will begin at 0. The number provided is a relative position.

If you press the rotary encoder switch down, it will display True .

Note that the key press line does not show up initially. Try pressing a key!

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To use the display_text feature of the MacroPad library, you need to instantiate it
by assigning it to a variable, e.g. text_lines =

macropad.display_text(title="MacroPad Info") . Once created, the title cannot

be updated. Note that if you want to be able to dynamically update the title, simply
instantiate it without a tittle ( text_lines = macropad.display_text() ), and treat

the first line of text as the title, which can be dynamically updated.

Once you've instantiated it, you can create lines of text below the title with dynamic

information in them, such as the key number being pressed or the relative position of
the rotary encoder. To do this, you use the text_lines object, and provide it a line

number and a string to display. Remember, Python begins counting at 0. For example,

to display a line of text with the rotary encoder relative position below the title, you
would include text_lines[0].text = "Rotary encoder

{}".format(macropad.encoder) in your code. To include a second line of code,

you would use text_lines[1].text = and provide a string to display.

This feature uses the Simple Text Display library; for advanced usage check out the

Simple Text Display documentation(https://adafru.it/U9D).

In your code, first, you import the MacroPad library, and then instantiate it.

Then, you create a text_lines variable, initialise the display_text feature by
assigning text_lines = macropad.display_text() , and, inside the parentheses,
provide it the title as a string, e.g. title="MacroPad Info" .

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Inside the loop, the first thing you do is setup to look for the key press by creating the

key_event variable and assigning it to macropad.keys.events.get() . Then, you

check to see if there is a key_event (i.e. a key being pressed) and if it is a key being
pressed ( key_event.pressed ). Then, if so, if so, update the first line of text to
appear on the display showing which key number ( key_event.key_number ) was

pressed.

Next, you display two more lines of text - one for the rotary encoder relative position

and one for the rotary encoder switch state. Each of these updates when you rotate

the rotary encoder or press on the rotary encoder switch.

Finally, you call text_lines.show() to make the lines of text show up on the

display.

That's all there is to displaying lines of text on the built-in display of the Adafruit

MacroPad using the CircuitPython MacroPad library!

MacroPad Display Image

The Adafruit MacroPad comes with a built in display. The MacroPad library makes it

super simple to display a CircuitPython-compatible bitmap image on the display. To

learn more about how to create a CircuitPython-compatible bitmap, check out this

guide(https://adafru.it/MbZ) - the difference here is, the MacroPad display is

monochrome, so you'll want a black and white image.

You can easily update the code to use any compatible bitmap you'd like, but for this

example, download the following image and save it to your CIRCUITPY drive as blink

a.bmp.

Update your code.py to the following.

Click the Download Project Bundle button below to download the necessary libraries

and the code.py file in a zip file. Extract the contents of the zip file, open the folder

that matches your CircuitPython version, and copy the entire lib folder and the code.

py file to your CIRCUITPY drive.

# SPDX-FileCopyrightText: Copyright (c) 2021 Kattni Rembor for Adafruit Industries
#

©Adafruit Industries Page 100 of 124