Adafruit FunHouse User Manual

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Adafruit FunHouse

Created by Melissa LeBlanc-Williams

Last updated on 2021-10-16 03:46:26 PM EDT

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Guide Contents

Guide Contents Overview Pinouts

TFT Display and Display Connector Power ESP32-S2 WiFi Module DotStar LEDs and Red LED STEMMA QT Digital/Analog Connectors Speaker and Sensors Reset and Boot Buttons User Buttons Capacitive Touch Pads and Slider PIR Sensor Port

Install UF2 Bootloader

Step 1. Download the tinyuf2_combo.bin file here Step 2. Place your board in bootloader mode

Check for a new serial / COM port

Step 3 Option A. Use the Web Serial ESPTool to upload

Enable Web Serial (For older chrome) Connecting Erasing the Contents Programming the Microcontroller

Step 3. Option B. Use esptool.py to upload (for advanced users)

Install ESPTool.py Test the Installation Installing the Bootloader

Step 4. Reset the board

CircuitPython

Set Up CircuitPython Option 1 - Load with UF2 Bootloader

Try Launching UF2 Bootloader

Option 2 - Use Chrome Browser To Upload BIN file Option 3 - Use esptool to load BIN file

CircuitPython Internet Libraries

Adafruit CircuitPython Library Bundle

CircuitPython Internet Test

Secrets File Connect to WiFi

Getting The Date & Time

Step 1) Make an Adafruit account Step 2) Sign into Adafruit IO Step 3) Get your Adafruit IO Key Step 4) Upload Test Python Code

FunHouse-Specific CircuitPython Libraries

Get Latest Adafruit CircuitPython Bundle Secrets

Welcome To CircuitPython

This guide will get you started with CircuitPython!

Installing the Mu Editor Download and Install Mu Using Mu

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Creating and Editing Code

Creating Code Editing Code

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

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

2. Eject or Sync the Drive After Writing Oh No I Did Something Wrong and Now The CIRCUITPY Drive Doesn't Show Up!!!

Back to Editing Code... Exploring Your First CircuitPython Program

Imports & Libraries Setting Up The LED Loop-de-loops What Happens When My Code Finishes Running? What if I don't have the loop?

More Changes Naming Your Program File Connecting to the Serial Console Are you using Mu?

Setting Permissions on Linux

Using Something Else? Interacting with the Serial Console The REPL Returning to the serial console Advanced Serial Console on Windows Windows 7 Driver What's the COM? Install Putty CircuitPython Libraries

Installing the CircuitPython Library Bundle Example Files

Copying Libraries to Your Board

Example: ImportError Due to Missing Library Library Install on Non-Express Boards Updating CircuitPython Libraries/Examples

CircuitPython Pins and Modules CircuitPython Pins

import board I2C, SPI, and UART What Are All the Available Names? Microcontroller Pin Names

CircuitPython Built-In Modules Advanced Serial Console on Mac and Linux What's the Port? Connect with screen Permissions on Linux Frequently Asked Questions

I have to continue using an older version of CircuitPython; where can I find compatible libraries? Is ESP8266 or ESP32 supported in CircuitPython? Why not? How do I connect to the Internet with CircuitPython? Is there asyncio support in CircuitPython?

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My RGB NeoPixel/DotStar LED is blinking funny colors - what does it mean? What is a MemoryError? What do I do when I encounter a MemoryError? Can the order of my import statements affect memory? How can I create my own .mpy files? How do I check how much memory I have free? Does CircuitPython support interrupts? Does Feather M0 support WINC1500? Can AVRs such as ATmega328 or ATmega2560 run CircuitPython? Commonly Used Acronyms

ESP32-S2 Bugs & Limitations

Cannot reinitialize certain peripherals (especially busio.I2C) No DAC-based audio output Deep Sleep & Wake-up sources

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? CPLAYBOOT, TRINKETBOOT, FEATHERBOOT, or GEMMABOOT Drive Not Present

You may have a different board. MakeCode MacOS Windows 10 Windows 7 or 8.1

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 CircuitPython RGB Status Light

CircuitPython 7.0.0 and Later CircuitPython 6.3.0 and earlier

ValueError: Incompatible .mpy file. CIRCUITPY Drive Issues

Easiest Way: Use storage.erase_filesystem() Old Way: For the Circuit Playground Express, Feather M0 Express, and Metro M0 Express: Old Way: For Non-Express Boards with a UF2 bootloader (Gemma M0, Trinket M0): Old Way: For non-Express Boards without a UF2 bootloader (Feather M0 Basic Proto, Feather Adalogger, Arduino Zero):

Running Out of File Space on Non-Express Boards

Delete something! Use tabs MacOS loves to add extra files. Prevent & Remove MacOS Hidden Files Copy Files on MacOS Without Creating Hidden Files Other MacOS Space-Saving Tips

Device Locked Up or Boot Looping Welcome to the Community!

Adafruit Discord Adafruit Forums Adafruit Github ReadTheDocs

CircuitPython Essentials

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Blink

LED Location Blinking an LED

Digital Input

LED and Button Controlling the LED with a Button

Built-In DotStar LEDs

DotStar Location DotStar Color and Brightness RGB LED Colors DotStar Rainbow

CPU Temperature

Microcontroller Location Reading the Microcontroller Temperature

Arduino IDE Setup Arduino Libraries Install Libraries

Adafruit DotStar Adafruit GFX Adafruit ST7735 and ST7789 Adafruit ImageReader Adafruit AHTX0 Adafruit DPS310

Arduino Basics

Using the Red LED Reading the Buttons Reading the Capacitive Touch Pads Using On-Board DotStars Using On-board Humidity and Temperature Sensor Using On-board Pressure Sensor Using the TFT Display

Arduino Self Test Example Downloads

Files:

Schematic Fab Print

Overview

Home is where the heart is...it's also where we keep all our electronic bits. So why not wire it up with sensors and actuators to turn our house into an electronic wonderland. Whether it's tracking the environmental temperature and humidity in your laundry room, or notifying you when someone is detected in the kitchen, to sensing when a window was left open, or logging when your cat leaves through the pet door, this board is designed to make it way easy to make WiFi-connected home automation projects.

The main processor is the ESP32-S2, which has the advantage of the low cost and power of the ESP32 with the flexibility of CircuitPython support thanks to native USB support. There's also Arduino support for this chip, and many existing ESP32 projects seem to run as-is. Note this chip does not have BLE support, but for WiFi projects its great. You can use it to connect to IoT services or just the Internet in general, with SSL support and this module has plenty of PSRAM for any kind of data processing.

The board is designed to make it easy to wire up sensors with little or no soldering. There are built in sensors for light, pressure, humidity and temperature sensors.

Three JST PH plugs allow for quick connection of STEMMA boards (https://adafru.it/RKb) that use digital or analog I/O, and there's a STEMMA QT port for any I2C devices. (https://adafru.it/NmD)

Here's what we included on this development board:

ESP32-S2 240MHz Tensilica processor - the next generation of ESP32, now with native USB so it can act like a keyboard/mouse, MIDI device, disk drive, etc! WROVER module has FCC/CE certification and comes with 4 MByte of Flash and 2 MByte of PSRAM - you can have huge data buffers

1.54" Color TFT display with 240x240 pixels (https://adafru.it/RKc). This petite display is one of our favorites, with SPI interface and a controllable backlight.

USB C power and data connector Five mini RGB DotStar LEDs on the top, for animations or easily-visible notification Three buttons can be used to wake up the ESP32 from deep-sleep, or select different modes

DPS310 (https://adafru.it/RKd) barometric pressure and temperature sensor AHT20 (https://adafru.it/RKe) relative humidity and temperature sensor

Plug in socket for Mini PIR sensor (https://adafru.it/RKf) (not included) Front facing light sensor

Speaker/Buzzer can play tones and beeps for audible notification. STEMMA QT port for attaching all sorts of I2C devices (https://adafru.it/HMF)

Three STEMMA 3 pin JST connectors for attaching NeoPixels (https://adafru.it/Cup), speakers (https://adafru.it/Gpf), servos (https://adafru.it/FWq) or

relays (https://adafru.it/NmC).

Three capacitive touch pads and one capacitive touch slider with 5 elements.

On/Off switch

Boot and Reset buttons for re-programming

Pinouts

The Funhouse has a display and so many great features. It's packed with buttons, lights, connectors and sensors. Time to take a tour!

TFT Display and Display Connector

Front and center is a 1.54" ST7789-based IPS Wide Angle TFT Display with 240x240 pixe ls.

Each pixel is 16-bit full color.

On the back, the display cable goes through the board to the display co nnector on the back.

Power

USB C port - This is used for both powering an d programming the board. You can

power it with any USB C cable and will request 5V from a USB C PD.

On/Off switch - This switch controls power to the board. If you plug in your board and

nothing happens, make sure the switch is flipped to "ON"!

ESP32-S2 WiFi Module

The ESP32-S2 WROVER module .

The ESP32-S2 is a highly-integrated, low-power, 2.4 GHz Wi-Fi System-on-Chip (SoC) solution

that now has built-in native USB as well as some other interesting new technolo gies like

Time of Flight distance measurem ents. With its state-of-the-art power a nd RF performance,

this SoC is an ideal choice for a wid e variety of application scenarios relating to the Internet

of Things (IoT) (https://adafru.it/B wq), wearable electronics (https://adafru.it/Osb), and smart

homes.

Please note, this is a single-core 240 MHz chip, so it won't be as fast as ESP32's with dual-core. Also, there is no Bluetooth support. However, we are super excited about the ESP32-S2's native USB which unlocks a lot of capabilities for advanced interfacing! This WROVER module comes with 4 MB flash and 2 MB PSRAM.

The 4 MB of flash is inside the module and is used for both program firmware and filesystem storage. For example, in CircuitPython, we have 3 MB set aside for program firmware (this includes two OTA option spots as well) and a 1MB section for CircuitPython scripts and files.

DotStar LEDs and Red LED

DotStar LEDs and red LED.

On the front of the board, along the top, are five addressab le RGB DotStar LEDs, so

you can light up the display with an y color or pattern. You can use DO TSTAR_CLOCK or

GPIO15 for the Clock pin and DOTSTAR_DATA or GPIO14 for th e Data pin to control

the DotStars.

Below the display, and slightly to th e right, is a red LED positioned at the top right of

the FunHouse door. It is use r-controllable for blinky needs. You c an blink this at any

time. This LED is attached to LED or GPIO37 .

STEMMA QT

STEMMA QT (https://adafru.it/Ft4) - This JST SH 4-pin connector breaks out I2C (SC L, SDA,

3.3V, GND). It allows you to connec t to various breakouts and sensors with STEMMA

QT connectors (https://adafru.it/HMF) or to other things usin g assorted associated

accessories (https://adafru.it/Ft6).

Works great with any STEMMA QT or Qwiic sensor/device

You can also use it with Grove I2C devices thanks to this handy cable (https://adafru.it/Ndk)

Digital/Analog Connectors

On the side are three connectors labeled A0, A1, and A2. These are STEMM A 3 pin

JST digital or analog connectors for

attaching NeoPixels (https://adafru .it/Cup), speakers (https://adafru.it/G pf), servos (https://adafru.it/FWq)

These pins can be analog inputs o r digital I/O. They are connected to GPIO17 for A0 ,

GPIO2 for A1 , and GPIO1 for A2 .

All three connectors have protectio n 1K resistors + 3.6V zener diodes so you can drive an

LED directly from the output. The m aximum current from these connec tors is 200mA.

All three ports are 'true' analog outputs and all three can be used for PW M as well as analog

inputs. The maximum input voltag e is 2.6V, after which the zener diodes will kick in to drain

excess voltage.

The power output is 5V by default , but a jumper can be cut/soldered to change it to 3.3V.

Speaker and Sensors

Towards the middle of the board, a t the bottom right corner of the displa y, is

a speaker/buzzer labeled with a musical note. This in cludes a mini class D amplifier on

DAC output GPIO42 and can play tones or lo-fi audio clips.

In the bottom right corner of the bo ard, on the left side of the cutout reg ion, is

a DPS310 pressure sensor, that can be used to sense the barometric pressure It is

connected to the I2C port and available on I2C address 0x77 .

Also in the bottom right corner of t he board, on the right side of the cut out region, is

an AHT20 Humidity and Temperature se nsor, that can be used to sense the humidity

and temperature. It is connected to the I2C port and available on I2C address 0x38 .

Below the display, and slightly to th e left, is a front-facing light sensor that is positioned

at the top left of the FunHouse do or.

Note: The light sensor is influenced by the display's backlight, use some tape to block the light if needed. More info, and a great chart here (https://adafru.it/doW).

Reset and Boot Buttons

Reset button - The rese t button is on the front below the dis play and to the right of the

FunHouse Door.

Boot button - The boot button is on the back and situated between the Digital/Analog

Ports and the ESP32-S2 module. This is connected to BOOT0 and can be use d to put

the board into ROM bootloader mo de. To enter ROM bootloader mode, hold down DFU

button while clicking reset button m entioned above. When in th e ROM bootloader, you

can upload code and query the chip using esptool .

User Buttons

On the front of the board, to the le ft of the display, there are three user-controllable

buttons labeled arrows for the top and bottom buttons. The buttons are on BUTTON_DOWN

or GPIO3 , BUTTON_ SELECT or GPIO4 , and BUTTON_UP or GPIO5 . They can be used to

wake up the ESP32-S2 from deep -sleep, or however you want to use them.

There are no pull-ups on board, use internal pulldowns for these pins - when the buttons are

pressed the IO pin labeled is set to HIGH

Capacitive Touch Pads and Slider

On the front of the board, to the le ft of the display and along the top, there are three

capacitive touch pads with ravens on top labeled CT6, CT7, and CT8 . The pads are on

CAP6 or GPIO6 , CAP7 or GPIO7 , and CAP8 or GPIO8 . They can be used like buttons.

On the right side of the board, there is a capacitive touch slider made up of 5 capacitive

touch pads. It has a tree on top. The pads are on CAP9 or GPIO9 , CAP10 or GPIO10 ,

CAP11 or GPIO11 , CAP12 or GPIO12 , and CAP13 or GPIO13 . They can be used as

separate buttons or a positional slider.

PIR Sensor Port

On the front of the FunHouse is a location to add the PIR sensor. It is in tended to be inserted

through the front and into the con nector on the back, but it could also w ork from the back.

When inserting, make sure the + a nd - symbols match up with the PIR sensor's markings or

it will short out the board.

The PIR sensor is connected to PIR_SENSE or GPIO16 .

Install UF2 Bootloader

If you're familiar with our other products and chipsets you may be famliar with our drag-n-drop bootloader, a.k.a UF2. We have a UF2 bootloader for the ESP32-S2, that will let you drag firmware on/off a USB disk drive.

However, thanks to the ROM bootloader, you don't have to worry about it if the UF2 bootloader is damaged. The ROM bootloader can never be disabled or erased, so its always there if you need it! You can simply re-load the UF2 bootloader (USB-disk-style) with the ROM bootloader (non-USB-drive)

You can use the TinyUF2 bootloader to load code directly, say CircuitPython or the binary output of an Arduino compilation or you can use it to load a

second

bootloader

on, like UF2 which has a drag-n-drop interface.

Step 1. Download the tinyuf2_combo.bin file here

Note that this file is 3MB but that's because the bootloader is near the end of the available flash. It's not actually 3MB large, most of the file is empty but its easier to program if we give you one combined 'swiss cheese' file. Save this file to your desktop or wherever you plan to run esptool from

This is a link to the latest .zip files. Just click the one for the FunHouse.

https://adafru.it/TSA

Step 2. Place your board in bootloader mode

Entering the bootloader is easy. Complete the following steps.

1. Make sure your ESP32-S2 is plugged into USB port to your computer using a data/sync cable. Charge-only cables will not work!

2. Turn on the On/Off switch - check that you see the OK light on so you know the board is powered, a prerequisite!

3. Press and hold the DFU / Boot0 button down. Don't let go of it yet!

4. Press and release the Reset button. You should have the DFU/Boot0 button pressed while you do this.

5. Now you can release the DFU / Boot0 button

Check for a new serial / COM port

The FunHouse comes with a bootloader pre-installed, so you should only need to follow these steps if you are having issues.



Unlike the M0 (SAMD21) and M4 (SAMD51) boards, there is no bootloader protection for the UF2 bootloader. That means it is possible to erase or damage the bootloader, especially if you upload Arduino sketches to ESP32S2 boards that doesn't "know" there's a bootloader it should not overwrite!



Installing the UF2 bootloader will erase your board's firmware which is also used for storing CircuitPython/Arduino/Files! Be sure to back up your data first.



https://adafru.it/TSA

On Windows check the Device ma nager - you will see a COM port, for example here its

COM88. You may also see anothe r "Other device" called ESP32-S2

It's best to do this with no other de v boards plugged in so you don't get confused about

which COM port is the ESP32-S2

On Mac/Linux you will need to find the tty name which lives under /dev

On Linux, try ls /dev/ttyS* for example, to find the matching serial port name . In this case it

shows up as /dev/ttyS87. If you don't see it listed try ls /dev/ttyA* on some Linux systems it

might show up like /dev/ttyACM0

On Mac, try ls /dev/cu.usbmodem* for exam ple, to find the matching serial port name. In this

case, it shows up as /dev/cu.u sbmodem01

It's best to do this with no other de v boards plugged in so you don't get confused about

which serial port is the ESP32-S2

Step 3 Option A. Use the Web Serial ESPTool to upload

The WebSerial ESPTool was designed to be a web-capable option for programming ESP32-S2 boards. It allows you to erase the contents of the microcontroller and program up to 4 files at different offsets.

You will have to use the Chrome browser for this to work, Safari and Firefox, etc are

not

supported because we need Web Serial and only Chrome is supporting it to the

level needed.

Enable Web Serial (For older chrome)

Visit chrome://flags from within Chrome. Find and enable the Experimental Web Platform

features

Restart Chrome

As of chrome 89, Web Serial is already enabled, so this step is only necessary on older browsers.



Connecting

In the Chrome browse r

visit https://adafruit.github.io/Adafruit_WebSerial_ESPTool/ (https://adafru.it/PMB) it should

look like the image to the left

Press the Connect butt on in the top right of the web browse r. You will get a pop up asking

you to select the COM or Serial po rt. You may want to remove all other USB devices

only

the ESP32-S2 board is attached, t hat way there's no confusion over multiple ports!

The Javascript code will now try to connect to the ROM bootloader. It may timeout for a bit

until it succeeds. On success, you will see that it is Connected and will print out a

unique MAC address identifying the board.

Once you have successfully conne cted, the command toolbar will appear.

Erasing the Contents

If you would like to erase the entire flash area so that you can start with a clean slate, you can use the erase feature. We recommend doing this if you are having issues.

To erase the contents, click the Era se button. You will be prompted whether you want to

continue. Click OK to continue or if you changed your mind, just click ca ncel.

Programming the Microcontroller

Programming the microcontroller can be done with up to 4 files at different locations, but with the tinyuf2combo BIN file, which you should have downloaded under Step 1 on this page, you only need to use 1 file.

You can click on Choose a file... from any of the available buttons. It will only attempt t o

program buttons with a file and a u nique location. Then select the Adafruit

CircuitPython BIN files (not the UF2 file!)

Verify that the Offse t box next to the file location you used is 0x0.

Once you choose a file, the button text will change to match your filename. You can then

select the Program button to start f lashing.

A progress bar will appear and after a minute or two, you will have written the firmware.

Step 3. Option B. Use esptool.py to upload (for advanced users)

Once you have entered ROM bootloader mode, you can then use Espressif's esptool program (https://adafru.it/E9p) to communicate with the chip! esptool is the 'official'

programming tool and is the most common/complete way to program an ESP chip.

Install ESPTool.py

You will need to use the command line / Terminal to install and run esptool .

You will also need to have pip and Python installed (any version!)

Install the latest version using pip (you may be able to run pip without the 3 depending on your setup):

pip3 install --upgrade esptool

Then, you can run:

esptool.py

Test the Installation

Run esptool.py in a new terminal/command line and verify you get something like the below:

After using the tool, press the reset button to get out of bootloader mode and launch the new firmware!



Run the following command, replacing the identifier after --port with the COMxx , /dev/cu.usbmodemxx or /dev/ttySxx you found above.

esptool.py --port COM88 chip_id

You should get a notice that it connected over that port and found an ESP32-S2

Installing the Bootloader

Run this command and replace the serial port name with your matching port and the file you just downloaded

esptool.py --port COM88 write_flash 0x0 tinyuf2_combo.bin

Don't forget to change the --port name to match.

There might be a bit of a 'wait' when programming, where it doesn't seem like it's working. Give it a minute, it has to erase the old flash code which can cause it to seem like it's not running.

You'll finally get an output like this:

Step 4. Reset the board

Double-click the RESET button to launch the bootloader. About a half second pause between clicks while the DotStars are purple seems to work well. You'll see a new disk drive on your computer with the name HOUSEBOOT.

You're now ready to copy the CircuitPython UF2 on to the drive which will set up CircuitPython!

Make sure you are running esptool v3.0 or higher, which adds ESP32-S2 support



CircuitPython

CircuitPython (https://adafru.it/tB7) is a derivative of MicroPython (https://adafru.it/f9W) 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.

Set Up CircuitPython

Follow the steps to get CircuitPython installed on your FunHouse.

https://adafru.it/RKB

Click the link above and download the latest .BIN and .UF2 file

(depending on how you program the ESP32S2 board you may need one or the other, might

as well get both)

Download and save it to your desktop (or wherever is handy).

Plug your FunHouse into your computer using a known-good USB cable.

A lot of people end up using charg e-only USB cables and it is very frus trating! So make sure

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

Option 1 - Load with UF2 Bootloader

This is by far the easiest way to load CircuitPython. However it requires your board has the UF2 bootloader installed. Some early boards do not (we hadn't written UF2

yet!) - in which case you can load using the built in ROM bootloader.

Still, try this first!

Try Launching UF2 Bootloader

Loading CircuitPython by drag-n-d rop UF2 bootloader is the easier way and we recommend

it.

Launch UF2 by double-clicking the Reset button (the one next to the USB C port). You may

have to try a few times to get the timing right.

About a half second pause betwe en clicks while the DotStars are purp le seems to work

well.

https://adafru.it/RKB

If the UF2 bootloader is installed, y ou will see a new disk drive appear called HOUSEBOOT

Copy the UF2 file you downloaded at the first step of this tutorial o nto

the HOUSEBOOT drive

If you're using Windows and you get an error at the end of the file copy that says Error from the file copy, Error 0x800701B1: A device which does not exist was specified. You can ignore this error, the bootloader sometimes disconnects without telling Windows, the install completed just fine and you can continue. If its really

annoying, you can also upgrade the bootloader (the latest version of the UF2 bootloader fixes this warning) (https://adafru.it/RLc)

Your board should auto-reset into CircuitPython, or you may need to pr ess reset.

A CIRCUITPY drive will appear. You're done! Go to the next pages.

Option 2 - Use Chrome Browser To Upload BIN file

The next best option is to try using the Chrome-browser version of esptool we have written. This is handy if you don't have Python on your computer, or something is really weird with your setup that makes esptool not run (which happens sometimes and isn't worth debugging!) You can follow along on the Install UF2

Bootloader (https://adafru.it/RLc) page and either load the UF2 bootloader and then come back to Option 1 on this page, or you can download the CircuitPython BIN file

directly using the tool in the same manner as the bootloader.

Option 3 - Use esptool to load BIN file

For more advanced users, you can upload with esptool to the ROM (hardware) bootloader instead!

Follow the initial steps found in the Run esptool and check connection section of the In stall

UF2 Bootloader page (https://adafru.it/RLc) to verify your environment is set up , your board is

successfully connected, and which port it's using.

In the final command to write a bin ary file to the board, replace the por t with your port, and

replace "firmware.bin" with the the file you downloaded above.

The output should look somethin g like the output in the image.

You will need to do a full erase prior to uploading new firmware.



Press reset to exit the bootloader.

Your CIRCUITPY drive should appear!

You're all set! Go to the next pages.

CircuitPython Internet Libraries

To use the internet-connectivity built into your ESP32-S2 with CircuitPython, you must first install a number of libraries. This page covers that process.

Adafruit CircuitPython Library Bundle

Download the Adafruit CircuitPython Bundle. You can find the latest release here:

https://adafru.it/ENC

Download the adafruit-circuitpython-bundle-version-mpy-*.zip bundle zip file, and unzip a folder of the same name. Inside you'll find a lib folder. The entire collection of libraries is too large to fit on the CIRCUITPY drive. Instead, add each library as you need it, this will reduce the space usage but you'll need to put in a little more effort.

At a minimum we recommend the following libraries, in fact we more than recommend. They're basically required. So grab them and install them into CIRCUITPY/lib now!

adafruit_requests.mpy - A requests-like library for HTTP commands. adafruit_dotstar.mpy - Helper library to use DotStar LEDs, often built into the boards so they're great for quick feedback

Once you have added those files, please continue to the next page to set up and test Internet connectivity

https://adafru.it/ENC

CircuitPython Internet Test

Once you have CircuitPython installed and the minimum libraries installed we can get your board connected to the Internet.

To get connected, you will need to start by creating a secrets.py file.

Secrets File

We expect people to share tons of projects as they build CircuitPython WiFi widgets. What we want to avoid is people accidentally sharing their passwords or secret tokens and API keys. So, we designed all our examples to use a secrets.py file, that is in your CIRCUITPY drive, to hold secret/private/custom data. That way you can share your main project without worrying about accidentally sharing private stuff.

Your secrets.py file should look like this:

# This file is where you kee p secret settings, passwords, and tokens! # If you put them in the cod e you risk committing that inf o or sharing it

secrets = { 'ssid' : 'home_wifi_netw ork', 'password' : 'wifi_passw ord', 'aio_username' : 'my_ada fruit_io_username', 'aio_key' : 'my_adafruit _io_key', 'timezone' : "America/Ne w_York", # http://worldtimeapi .org/timezones }

Copy and paste that text/code into a file called secrets.py and save it to your CIRCUITPY folder like so:

Inside is a python dictionary named secrets with a line for each entry. Each entry has an entry name (say 'ssid' ) and then a colon to separate it from the entry key 'home

ssid' and finally a comma ,

At a minimum you'll need to adjust the ssid and password for your local WiFi setup so do that now!

As you make projects you may need more tokens and keys, just add them one line at a time. See for example other tokens such as one for accessing github or the hackaday API. Other non-secret data like your timezone can also go here, just cause its called secrets doesn't mean you can't have general customization data in there!

For the correct time zone string, look at http://worldtimeapi.org/timezones (https://adafru.it/EcP) and remember that if your city is not listed, look for a city in the same time zone, for example Boston, New York, Philadelphia, Washington DC, and Miami are all on the same time as New York.

Of course, don't share your secrets.py - keep that out of GitHub, Discord or other project-sharing sites.

Connect to WiFi

OK now you have your secrets setup - you can connect to the Internet using the Requests module.

First make sure you are running the latest version of Adafruit CircuitPython (https://adafru.it/Amd) for your board.

Next you'll need to install the necessary libraries to use the hardware--carefully follow the steps to find and install these libraries from Adafruit's CircuitPython library

bundle (https://adafru.it/zdx). Our introduction guide has a great page on how to install the library bundle (https://adafru.it/ABU).

adafruit_requests

neopixel

Before continuing make sure your board's CIRCUITPY/lib folder or root filesystem has the above files copied over.

Don't share your secrets.py file, it has your passwords and API keys in it!



Once that's done, load up the following example using Mu or your favorite editor:

import ipaddress import ssl import wifi import socketpool import adafruit_requests

# URLs to fetch from TEXT_URL = "http://wifitest. adafruit.com/testwifi/index.ht ml" JSON_QUOTES_URL = "https://w ww.adafruit.com/api/quotes.php " JSON_STARS_URL = "https://ap i.github.com/repos/adafruit/ci rcuitpython"

# Get wifi details and more from a secrets.py file try: from secrets import secr ets except ImportError: print("WiFi secrets are kept in secrets.py, please add them there!") raise

print("ESP32-S2 WebClient Te st")

print("My MAC addr:", [hex(i ) for i in wifi.radio.mac_addr ess])

print("Available WiFi networ ks:") for network in wifi.radio.st art_scanning_networks(): print("\t%s\t\tRSSI: %d\ tChannel: %d" % (str(network.s sid, "utf-8"), network.rssi, ne twork.channel)) wifi.radio.stop_scanning_net works()

print("Connecting to %s"%sec rets["ssid"]) wifi.radio.connect(secrets[" ssid"], secrets["password"]) print("Connected to %s!"%sec rets["ssid"]) print("My IP address is", wi fi.radio.ipv4_address)

ipv4 = ipaddress.ip_address( "8.8.4.4") print("Ping google.com: %f m s" % (wifi.radio.ping(ipv4)*10 00))

pool = socketpool.SocketPool (wifi.radio) requests = adafruit_requests .Session(pool, ssl.create_defa ult_context())

print("Fetching text from", TEXT_URL) response = requests.get(TEXT _URL) print("-" * 40) print(response.text) print("-" * 40)

print("Fetching json from", JSON_QUOTES_URL) response = requests.get(JSON _QUOTES_URL) print("-" * 40) print(response.json()) print("-" * 40)

print()

print("Fetching and parsing json from", JSON_STARS_URL) response = requests.get(JSON _STARS_URL) print("-" * 40) print("CircuitPython GitHub Stars", response.json()["starg azers_count"]) print("-" * 40)

print("done")

And save it to your board. Make sure the file is named code.py.

Open up your REPL, you should see something like the following:

In order, the example code...

Checks the ESP32-S2's MAC address.

print("My MAC addr:", [hex(i ) for i in wifi.radio.mac_addr ess])

Performs a scan of all access points and prints out the access point's name (SSID), signal strength (RSSI), and channel.

print("Avaliable WiFi networ ks:") for network in wifi.radio.st art_scanning_networks(): print("\t%s\t\tRSSI: %d\ tChannel: %d" % (str(network.s sid, "utf-8"), network.rssi, ne twork.channel)) wifi.radio.stop_scanning_net works()

Connects to the access point you defined in the secrets.py file, prints out its local IP address, and attempts to ping google.com to check its network connectivity.

print("Connecting to %s"%sec rets["ssid"]) wifi.radio.connect(secrets[" ssid"], secrets["password"]) print(print("Connected to %s !"%secrets["ssid"])) print("My IP address is", wi fi.radio.ipv4_address)

ipv4 = ipaddress.ip_address( "8.8.4.4") print("Ping google.com: %f m s" % wifi.radio.ping(ipv4))

The code creates a socketpool using the wifi radio's available sockets. This is performed so we don't need to re-use sockets. Then, it initializes a a new instance of the

requests (https://adafru.it/E9o) interface - which makes getting data from the internet

really really easy.

pool = socketpool.SocketPool (wifi.radio) requests = adafruit_requests .Session(pool, ssl.create_defa ult_context())

To read in plain-text from a web URL, call requests.get - you may pass in either a http, or a http s url for SSL connectivity.

print("Fetching text from", TEXT_URL) response = requests.get(TEXT _URL) print("-" * 40) print(response.text) print("-" * 40)

Requests can also display a JSON-formatted response from a web URL using a call to requests.get .

print("Fetching json from", JSON_QUOTES_URL) response = requests.get(JSON _QUOTES_URL) print("-" * 40) print(response.json()) print("-" * 40)

Finally, you can fetch and parse a JSON URL using requests.get . This code snippet obtains the stargazers_count field from a call to the GitHub API.

OK you now have your ESP32-S2 board set up with a proper secrets.py file and can connect over the Internet. If not, check that your secrets.py file has the right ssid and password and retrace your steps until you get the Internet connectivity working!

Getting The Date & Time

A very common need for projects is to know the current date and time. Especially when you want to deep sleep until an event, or you want to change your display based on what day, time, date, etc. it is

Determining the correct local time is really really hard. There are various time zones, Daylight Savings dates, leap seconds, etc. Trying to get NTP time and then backcalculating what the local time is, is extraordinarily hard on a microcontroller just isn't worth the effort and it will get out of sync as laws change anyways.

For that reason, we have the free adafruit.io time service. Free for anyone, with a free adafruit.io account. You

do need an account

because we have to keep

accidentally mis-programmed-board from overwhelming adafruit.io and lock them out temporarily. Again, it's free!

Step 1) Make an Adafruit account

It's free! Visit https://accounts.adafruit.com/ (https://adafru.it/dyy) to register and make an account if you do not already have one

Step 2) Sign into Adafruit IO

Head over to io.adafruit.com (https://adafru.it/fsU) and click Sign In to log into IO using your Adafruit account. It's free and fast to join.

Step 3) Get your Adafruit IO Key

Click on My Key in the top bar

You will get a popup with your Username and Key (In this screenshot, we've covered it with red blocks)

Go to your secrets.py file on your CIRCUITPY drive and add three lines for aio_username , aio_key and timezone so you get something like the following:

# This file is where you kee p secret settings, passwords, and tokens! # If you put them in the cod e you risk committing that inf o or sharing it

The timezone is optional, if you don't have that entry, adafruit.io will guess your timezone based on geographic IP address lookup. You can visit

http://worldtimeapi.org/timezones (https://adafru.it/EcP) to see all the time zones available (even though we do not use worldtimeapi for time-keeping we do use the same

time zone table)

Step 4) Upload Test Python Code

This code is like the Internet Test code from before, but this time it will connect to adafruit.io and get the local time

There are other services like WorldTimeAPI, but we don't use those for our guides because they are nice people and we don't want to accidentally overload their site. Also, there's a chance it may eventually go down or also require an account.



import ipaddress import ssl import wifi import socketpool import adafruit_requests import secrets

TEXT_URL = "http://wifitest. adafruit.com/testwifi/index.ht ml" JSON_QUOTES_URL = "https://w ww.adafruit.com/api/quotes.php " JSON_STARS_URL = "https://ap i.github.com/repos/adafruit/ci rcuitpython"

# Get wifi details and more from a secrets.py file try: from secrets import secr ets except ImportError: print("WiFi secrets are kept in secrets.py, please add them there!") raise

# Get our username, key and desired timezone aio_username = secrets["aio_ username"] aio_key = secrets["aio_key"] location = secrets.get("time zone", None) TIME_URL = "https://io.adafr uit.com/api/v2/%s/integrations /time/strftime?x-aio-key=%s" % (aio_username, aio_key) TIME_URL += "&fmt=%25Y-%25m- %25d+%25H%3A%25M%3A%25S.%25L+% 25j+%25u+%25z+%25Z"

print("ESP32-S2 Adafruit IO Time test")

print("My MAC addr:", [hex(i ) for i in wifi.radio.mac_addr ess])

print("Connecting to %s"%sec rets["ssid"]) wifi.radio.connect(secrets[" ssid"], secrets["password"]) print("Connected to %s!"%sec rets["ssid"]) print("My IP address is", wi fi.radio.ipv4_address)

ipv4 = ipaddress.ip_address( "8.8.4.4") print("Ping google.com: %f m s" % wifi.radio.ping(ipv4))

pool = socketpool.SocketPool (wifi.radio) requests = adafruit_requests .Session(pool, ssl.create_defa ult_context())

print("Fetching text from", TIME_URL) response = requests.get(TIME _URL) print("-" * 40) print(response.text) print("-" * 40)

After running this, you will see something like the below text. We have blocked out the part with the secret username and key data!

Note at the end you will get the date, time, and your timezone! If so, you have correctly configured your secrets.py and can continue to the next steps!

FunHouse-Specific CircuitPython Libraries

To use all the amazing features of your FunHouse with CircuitPython, you must first install a number of libraries. This page covers that process.

Get Latest Adafruit CircuitPython Bundle

Download the Adafruit CircuitPython Library Bundle. You can find the latest release here:

https://adafru.it/ENC

Download the adafruit-circuitpython-bundle-version-mpy-*.zip bundle zip file, and unzip a folder of the same name. Inside you'll find a lib folder. The entire collection of libraries is too large to fit on the CIRCUITPY drive. Therefore, you'll need to copy the necessary libraries to your board individually.

At a minimum, the following libraries are required. Copy the following folders or .mpy files to the lib folder on your CIRCUITPY drive. If the library is a folder, copy the entire folder to the lib folder on your board.

At a minimum we recommend the following libraries, in fact we more than recommend. They're basically required. So grab them and install them into CIRCUITPY/lib now!

Library folders (copy the whole folder over to lib):

adafruit_funhouse - This is a helper library designed for using all of the features of the FunHouse, including networking, buttons, DotStars, etc. adafruit_portalbase - This library is the base library that adafruit_funhouse is built on top of. adafruit_bitmap_font - There is fancy font support, and it's easy to make new fonts. This library reads and parses font files. adafruit_display_text - This library displays text on the screen. adafruit_io - This library helps connect the FunHouse to our free data logging and viewing service adafruit_minimqtt - MQTT library required for communicating with the MQTT Server

Library files:

adafruit_requests.mpy - This library allows us to perform HTTP requests and get responses back from servers. GET/POST/PUT/PATCH - they're all in here! adafruit_fakerequests.mpy - This library allows you to create fake HTTP requests by using local files. adafruit_miniqr.mpy - QR creation library lets us add easy-to-scan 2D barcodes to the E-Ink display adafruit_dotstar.mpy - This library is used to control the onboard DotStars. simpleio.mpy - This library is used for tone generation. adafruit_ahtx0.mpy - This is used for the Humidity and Temperature Sensor adafruit_dps310.mpy- This is used for the Barometric Pressure Sensor

Secrets

Even if you aren't planning to go online with your FunHouse, you'll need to have a secrets.py file in the root directory (top level) of your CIRCUITPY drive. If you do not intend to connect to wireless, it does not need to have valid data in it. Here's more info on the secrets.py file (https://adafru.it/P3b).

https://adafru.it/ENC

Welcome To CircuitPython

So, you've got this new CircuitPython compatible board. You plugged it in. Maybe it showed up as a disk drive called CIRCUITPY. Maybe it didn't! Either way, you need to know where to go from here. Well, we've got you covered!

This guide will get you started with CircuitPython!

There are many amazing things about your new board. One of them is the ability to run CircuitPython. You may have seen that name on the Adafruit site somewhere. Not sure what it is? We can help!

"But I've never coded in my life. There's no way I do it!" You absolutely can! CircuitPython is designed to help you learn from the ground up. If you're new to everything, this is the place to start!

This guide will walk you through how to get started with CircuitPython. You'll learn how to install CircuitPython, get updated to the newest version of CircuitPython, how to setup a serial connection, and how to edit the files.

Welcome to CircuitPython!

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!

Download and Install Mu

Download Mu from https://codewith.m u (https://adafru.it/Be6). Click the Dow nload or Start

Here links there for downloads a nd installation instructions. The website has a wealth of

other information, including extensive tutorials and and how-to's.

Using 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 M ode button in the upper left,

and then choose "CircuitPython" i n the dialog box that appears.

Mu attempts to auto-detect your board, so please plug in your CircuitPython device and

make sure it shows up as a CIRCUIT PY drive before starting 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.

Mu is our recommended editor - please use it (unless you are an experienced coder with a favorite editor already!)



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. In this section, we're going to cover 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. We strongly recommend 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 basic text editors built into every operating system such as Notepad on Windows, TextEdit on Mac, and gedit on Linux. However, many of these editors don't write back changes immediately to files that you edit. That can cause problems when using CircuitPython. See the Editing

Code (https://adafru.it/id3) section below. If you want to skip that section for now, 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.)

Creating Code

Open your editor, and create a new file. If you are using Mu, click the New button in the top

left

Copy and paste the following code into your editor:

import board import digitalio import time

led = digitalio.DigitalInOut (board.LED) led.direction = digitalio.Di rection.OUTPUT

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

If you're using QT Py or a Trinkey, please download the NeoPixel blink example (https://adafru.it/UDU).

It will look like this - note that unde r the while True: line, the next four lines have spac es to

indent them, but they're indented exactly the same amount. All other lines have no spaces

before the text.

The 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 QT Py or the Trinkeys!



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.



Save this file as code .py on your CIRCUITPY drive.

On each board (except the ItsyBitsy nRF52840) you'll find a tiny red LED. On the ItsyBitsy nRF52840, you'll find a tiny blue LED.

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

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

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 just one warning we have to give you before we continue...

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.

However, you must wait until the file is done being saved before unplugging or resetting your board! On Windows using some editors this can sometimes take up to 90 seconds, on Linux it can take 30 seconds to complete because the text editor does not save the file completely. Mac OS does not seem to have this delay, which is

nice!

This is really important to be aware of. 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 few ways to avoid this:

Don't Click Reset or Unplug!



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

Recommended editors:

mu (https://adafru.it/Be6) is an editor that safely writes all changes (it's also our recommended editor!) emacs (https://adafru.it/xNA) is also an editor that will fulIy write files on save (https://adafru.it/Be7)

Sublime Text (https://adafru.it/xNB) safely writes all changes Visual Studio Code (https://adafru.it/Be9) appears to safely write all changes

gedit on Linux appears to safely write all changes

IDLE (https://adafru.it/IWB), in Python 3.8.1 or later, was fixed (https://adafru.it/IWD) to write all changes immediately thonny (https://adafru.it/Qb6) fully writes files on save

Recommended

only

with particular settings or with add-ons:

vim (https://adafru.it/ek9) / vi safely writes all changes. But set up vim to not write swapfiles (https://adafru.it/ELO) (.swp files: temporary records of your edits) to

CIRCUITPY. Run vim with vim -n , set the no swapfile option, or set the directory option to write swapfiles elsewhere. Otherwise the swapfile writes trigger restarts of

your program. The PyCharm IDE (https://adafru.it/xNC) is safe if "Safe Write" is turned on in Settings->System Settings->Synchronization (true by default). If you are using Atom (https://adafru.it/fMG), install the fsync-on-save package (https://adafru.it/E9m) so that it will always write out all changes to files on CIRCUITPY .

SlickEdit (https://adafru.it/DdP) works only if you add a macro to flush the disk (https://adafru.it/ven).

don't

recommend these editors:

notepad (the default Windows editor) and N otepad++ can be slow to write, so we recommend the editors above! If you are using notepad, be sure to eject the drive (see below)

IDLE in Python 3.8.0 or earlier does not force out changes immediately nano (on Linux) does not force out changes geany (on Linux) does not force out changes Anything else - we haven't tested other editors so please use a recommended one!

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.

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.



Back to Editing Code...

Now! Let's try editing the program you added to your board. Open your code.py file into your editor. We'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.Di rection.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? Let's find out!

Exploring Your First CircuitPython Program

First, we'll take a look at the code we're editing.

Here is the original code again:

import board import digitalio import time

led = digitalio.DigitalInOut (board.LED) led.direction = digitalio.Di rection.OUTPUT

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

Imports & Libraries

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. The files built into CircuitPython are called modules, and the files you load separately are called libraries. Modules are built into CircuitPython. Libraries are stored on your CIRCUITPY drive in a folder called lib.

import board import digitalio import time

The import statements tells the board that you're going to use a particular library in your code. In this example, we imported three modules: board , digitalio , and time . All

three of these modules are built into CircuitPython, so no separate library files are needed. That's one of the things that makes this an excellent first example. You don't need any thing extra to make it work! board gives you access to the

hardware on your board

, digitalio lets you

access that hardware as inputs/outputs

and time let's you

pass time by 'sleeping'

Setting Up The LED

The next two lines setup the code to use the LED.

led = digitalio.DigitalInOut (board.LED) led.direction = digitalio.Di rection.OUTPUT

Your board knows the red LED as LED . So, we initialise that pin, and we set it to output. We set led to equal the rest of that information so we don't have to type it all out

again later in our code.

Loop-de-loops

The third section starts with a while statement. while True: essentially means, "forever do the following:". while True: creates a loop. Code will loop "while" the condition

is "true" (vs. false), and as True is never False, the code will loop forever. All code that is indented under while True: is "inside" the loop.

Inside our loop, we have four items:

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

First, we have led.value = True . This line tells the LED to turn on. On the next line, we have time.sleep(0.5) . This line is telling CircuitPython to pause running code for 0.5

seconds. Since this is between turning the led on and off, the led will be on for 0.5 seconds.

The next two lines are similar. led.value = False tells the LED to turn off, and time.sleep(0.5) tells CircuitPython to pause for another 0.5 seconds. This occurs between

turning the led off and back on so the LED will be off for 0.5 seconds too.

Then the loop will begin again, and continue to do so as long as the code is running!

So, when you changed the first 0.5 to 0.1 , you decreased the amount of time that the code leaves the LED on. So it blinks on really quickly before turning off!

Great job! You've edited code in a CircuitPython program!

What Happens When My Code Finishes Running?

When your code finishes running, CircuitPython resets your microcontroller board to prepare it for the next run of code. That means any set up you did earlier no longer applies, and the pin states are reset.

For example, try reducing the above example to led.value = True . The LED will flash almost too quickly to see, and turn off. This is because the code finishes running and



resets the pin state, and the LED is no longer receiving a signal.

To that end, most CircuitPython programs involve some kind of loop, infinite or otherwise

What if I don't have the loop?

If you don't have the loop, the code will run to the end and exit. This can lead to some unexpected behavior in simple programs like this since the "exit" also resets the state of the hardware. This is a different behavior than running commands via REPL. So if you are writing a simple program that doesn't seem to work, you may need to add a loop to the end so the program doesn't exit.

The simplest loop would be:

while True:

pass

And remember - you can press to exit the loop.

See also the Behavior section in the docs (https://adafru.it/Bvz).

More Changes

We don't have to stop there! Let's keep going. Change the second 0.5 to 0.1 so it looks like this:

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.txt, code.py, main.txt and main.py. CircuitPython looks for those files, in that order, and then runs the first one it finds. While we suggest using code.py as 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 looks like this:

print("Hello, world!")

This line would result in:

Hello, world!

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

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 print those too.

The serial console requires a terminal program. A terminal is a program that gives you a text-based interface to perform various tasks.

sudo apt purge modemmanager

Are you using Mu?

If so, good news! The serial console is built into Mu and will autodetect your board making using the REPL

really really easy

Please note that Mu does yet not work with nRF52 or ESP8266-based CircuitPython boards, skip down to the next section for details on using a terminal program.

First, make sure your CircuitPython board is plugged in. If you are using Windows 7, make

sure you installed the drivers (https://adafru.it/Amd).

Once in Mu, look for the Serial button in the menu and click it.

Setting Permissions on Linux

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

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 modemmanager service might be interfering. Just remove it; it doesn't have much use unless you're still using dial-up modems. To remove, type this command at a shell:



Serial Console on Mac and Linux (https://adafru.it/AAI) 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 as a separate program.

Windows requires you to download a terminal program, check out this page for more details (https://adafru.it/AAH)

Mac and Linux both have one built in, though other options are available for download, check this page for more details (https://adafru.it/AAI)

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, we'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

led = digitalio.DigitalInOut (board.LED) led.direction = digitalio.Di rection.OUTPUT

while True: print("Hello, CircuitPyt hon!") 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.

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!

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 we can see how it is used.

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

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. We 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!

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. 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.

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, 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 there is no code running, you will enter the REPL immediately after pressing Ctrl + C. There is no information about what your board was doing before you interrupted it because there is no code running.

Either way, 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.

From this prompt you can run all sorts of commands and code. The first thing we'll do is run help() . This will tell us 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.

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, please do `help("modules")`. Remember the libraries 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 libraries built into CircuitPython. We discussed how 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!

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." We'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. As we said though, 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 libraries are available and explore those libraries.

Try typing more into the REPL to see what happens!

Returning to the serial console

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

You can return to the REPL at any time!

Advanced Serial Console on Windows

Windows 7 Driver

If you're using Windows 7 (or 8 or 8.1), use the link below to download the driver package. You will not need to install drivers on Mac, Linux or Windows 10.

strongly

encourage you to upgrade to Windows 10 if you are still using Windows 7 or Windows 8 or 8.1. Windows 7 has reached end-of-life and no longer receives

security updates. A free upgrade to Windows 10 is still available (https://adafru.it/RWc).

https://adafru.it/AB0

What's the COM?

First, you'll want to find out which serial port your board is using. When you plug your board in to USB on your computer, it connects to a serial port. The port is like a door through which your board can communicate with your computer using USB.

We'll use Windows Device Manager to determine which port the board is using. The easiest way to determine which port the board is using is to first check without the board plugged in. Open Device Manager. Click on Ports (COM & LPT). You should find something already in that list with (COM#) after it where # is a number.

Now plug in your board. The Device Manager list will refresh and a new item will appear under Ports (COM & LPT). You'll find a different (COM#) after this item in the list.

https://adafru.it/AB0

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.

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Sometimes the item will refer to the name of the board. Other times it may be called something like USB Serial Device, as seen in the image above. Either way, there is a new (COM#) following the name. This is the port your board is using.

Install Putty

If you're using Windows, you'll need to download a terminal program. We're going to use PuTTY.

The first thing to do is download the latest version of PuTTY (https://adafru.it/Bf1). You'll want to download the Windows installer file. It is most likely that you'll need the 64-bit version. Download the file and install the program on your machine. If you run into issues, you can try downloading the 32-bit version instead. However, the 64-bit version will work on most PCs.

Now you need to open PuTTY.

Under Connection type: choose the button next to Serial. In the box under Serial line, enter the serial port you found that your board is using. In the box under Speed , enter 115200. This called the baud rate, which is the speed in bits per second that data is sent over the serial connection. For boards with built in USB it doesn't matter so much but for ESP8266 and other board with a separate chip, the speed required by the board is 115200 bits per second. So you might as well just use 115200!

If you want to save those settings for later, use the options under Load, save or delete a stored session. Enter a name in the box under Saved Sessions, and click the Save button on the right.

Once your settings are entered, you're ready to connect to the serial console. Click "Open" at the bottom of the window. A new window will open.

If no code is running, the window will either be blank or will look like the window above. Now you're ready to see the results of your code.

Great job! You've connected to the serial console!

CircuitPython Libraries

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 awesome 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.

CircuitPython libraries work in the same way as regular Python modules so the Python docs (https://adafru.it/rar) are a great reference for how it all should work. In Python terms, we 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, we provide a bundle full of our libraries.

Our bundle and releases 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.

Installing the CircuitPython Library Bundle

We're constantly updating and improving our libraries, so we don't (at this time) ship our CircuitPython boards with the full library bundle. Instead, you can find example code in the guides for your board that depends on external libraries. Some of these libraries may be available from us at Adafruit, some may be written by community members!

Either way, as you start to explore CircuitPython, you'll want to know how to get libraries on board.

You can grab the latest Adafruit CircuitPython Bundle release by clicking the button below.

Note: Match up the bundle version with the version of CircuitPython you are running - 3.x library for running any version of CircuitPython 3, 4.x for running any version of CircuitPython 4, etc. If you mix libraries with major CircuitPython versions, you will most likely get errors due to changes in library interfaces possible during major version changes.

https://adafru.it/ENC

If you need another version, you can also visit the bundle release page (https://adafru.it/Ayy) which will let you select exactly what version you're looking for, as well as information about changes.

Either way, download the version that matches your CircuitPython firmware version. If you don't know the version, look at the initial prompt in the CircuitPython REPL, which reports the version. For example, if you're running v4.0.1, download the 4.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.

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.

As we continue to develop CircuitPython and create new releases, we 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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https://adafru.it/ENC

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

Example Files

All example files from each library are now included in the bundles, 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 you'll want to create a lib folder on your CIRCUITPY drive. Open the drive, right click, choose the option to create a new folder, and call it lib. 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.

This also applies to example files. They are only supplied as raw .py files, so they may need to be converted to .mpy using the mpy-cross utility if you encounter

MemoryErrors . This is discussed in the CircuitPython Essentials Guide (https://adafru.it/CTw). Usage is the same as described above in the Express Boards section. Note:

If you do not place examples in a separate folder, you would remove the examples from the import statement.

Example: ImportError Due to Missing Library

If you choose to load libraries as you need them, you may write up code that tries to use a library you haven't yet loaded. We're going to 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 blinky example.

import board import time import simpleio

led = simpleio.DigitalOut(bo ard.D13)

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

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

We have an ImportError . It says there is no module named 'simpleio' . That's the one we just included in our 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 we'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 a Trinket M0 or Gemma M0, you'll want to follow the same steps in the example above to install libraries as you need them. You don't always need to wait for an ImportError as you probably know what library you added to your code. Simply open the lib folder you downloaded, find the library you need, and drag it to the lib

folder on your CIRCUITPY drive.

You may end up running out of space on your Trinket M0 or Gemma M0 even if you only load libraries as you need them. There are a number of steps you can use to try to resolve this issue. You'll find them in the Troubleshooting page in the Learn guides for your board.

Updating CircuitPython Libraries/Examples

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

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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.

CircuitPython Pins and Modules

CircuitPython is designed to run on microcontrollers and allows you to interface with all kinds of sensors, inputs and other hardware peripherals. There are tons of guides showing how to wire up a circuit, and use CircuitPython to, for example, read data from a sensor, or detect a button press. Most CircuitPython code includes hardware setup which requires various modules, such as board or digitalio . You import these modules and then use them in your code. How does CircuitPython know to look for

hardware in the specific place you connected it, and where do these modules come from?

This page explains both. You'll learn how CircuitPython finds the pins on your microcontroller board, including how to find the available pins for your board and what each pin is named. You'll also learn about the modules built into CircuitPython, including how to find all the modules available for your board.

CircuitPython Pins

When using hardware peripherals with a CircuitPython compatible microcontroller, you'll almost certainly be utilising pins. This section will cover how to access your board's pins using CircuitPython, how to discover what pins and board-specific objects are available in CircuitPython for your board, how to use the board-specific objects, and how to determine all available pin names for a given pin on your board.

import board

When you're using any kind of hardware peripherals wired up to your microcontroller board, the import list in your code will include import board . The board module is

built into CircuitPython, and is used to provide access to a series of board-specific objects, including pins. Take a look at your microcontroller board. You'll notice that next to the pins are pin labels. You can always access a pin by its pin label. However, there are almost always multiple names for a given pin.

To see all the available board-specific objects and pins for your board, enter the REPL ( >>> ) and run the following commands:

import board dir(board)

Here is the output for the QT Py.

The following pins have labels on the physical QT Py board: A0, A1, A2, A3, SDA, SCL, TX, RX, SCK, MISO, and MOSI. You see that there are many more entries available in board than the labels on the QT Py.

You can use the pin names on the physical board, regardless of whether they seem to be specific to a certain protocol.

For example, you do not

have

to use the SDA pin for I2C - you can use it for a button or LED.

On the flip side, there may be multiple names for one pin. For example, on the QT Py, pin A0 is labeled on the physical board silkscreen, but it is available in CircuitPython as both A0 and D0 . For more information on finding all the names for a given pin, see the What Are All the Available Pin Names? (https://adafru.it/QkA)

section below.

The results of dir(board) for CircuitPython compatible boards will look similar to the results for the QT Py in terms of the pin names, e.g. A0, D0, etc. However, some

boards, for example, the Metro ESP32-S2, have different styled pin names. Here is the output for the Metro ESP32-S2.

Note that most of the pins are named in an IO# style, such as IO1 and IO2. Those pins on the physical board are labeled only with a number, so an easy way to know how to access them in CircuitPython, is to run those commands in the REPL and find the pin naming scheme.

I2C, SPI, and UART

You'll also see there are often (but not always!) three special board-specific objects included: I2C , SPI , and UART - each one is for the default pin-set used for each of

the three common protocol busses they are named for. These are called

singletons

What's a singleton? When you create an object in CircuitPython, you are

instantiating

('creating') it. Instantiating an object means you are creating an instance of the

If your code is failing to run because it can't find a pin name you provided, verify that you have the proper pin name by running these commands in the REPL.

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object with the unique values that are provided, or "passed", to it.

For example, When you instantiate an I2C object using the busio module, it expects two pins: clock and data, typically SCL and SDA. It often looks like this:

i2c = busio.I2C(board.SCL, b oard.SDA)

Then, you pass the I2C object to a driver for the hardware you're using. For example, if you were using the TSL2591 light sensor and its CircuitPython library, the next line of code would be:

tsl2591 = adafruit_tsl2591.T SL2591(i2c)

However, CircuitPython makes this simpler by including the I2C singleton in the board module. Instead of the two lines of code above, you simply provide the singleton

as the I2C object. So if you were using the TSL2591 and its CircuitPython library, the two above lines of code would be replaced with:

tsl2591 = adafruit_tsl2591.T SL2591(board.I2C())

This eliminates the need for the busio module, and simplifies the code. Behind the scenes, the board.I2C() object is instantiated when you call it, but not before, and on

subsequent calls, it returns the same object. Basically, it does not create an object until you need it, and provides the same object every time you need it. You can call

board.I2C() as many times as you like, and it will always return the same object.

What Are All the Available Names?

Many pins on CircuitPython compatible microcontroller boards have multiple names, however, typically, there's only one name labeled on the physical board. So how do you find out what the other available pin names are? Simple, with the following script! Each line printed out to the serial console contains the set of names for a particular pin.

On a microcontroller board running CircuitPython, connect to the serial console. Then, save the following as code.py on your CIRCUITPY drive.

"""CircuitPython Essentials Pin Map Script""" import microcontroller import board

board_pins = [] for pin in dir(microcontroll er.pin): if isinstance(getattr(mi crocontroller.pin, pin), micro controller.Pin): pins = [] for alias in dir(boa rd): if getattr(board , alias) is getattr(microcontr oller.pin, pin): pins.append( "board.{}".format(alias)) if len(pins) > 0: board_pins.appen d(" ".join(pins)) for pins in sorted(board_pin s): print(pins)

Here is the result when this script is run on QT Py:

Each line represents a single pin. Find the line containing the pin name that's labeled on the physical board, and you'll find the other names available for that pin. For example, the first pin on the board is labeled A0. The first line in the output is board.A0 board.D0 . This means that you can access pin A0 with both board.A0 and

board.D0 .

You'll notice there are two "pins" that aren't labeled on the board but appear in the list: board.NEOPIXEL and board.NEOPIXEL_POWER . Many boards have several of

these special pins that give you access to built-in board hardware, such as an LED or an on-board sensor. The Qt Py only has one on-board extra piece of hardware, a NeoPixel LED, so there's only the one available in the list. But you can also control whether or not power is applied to the NeoPixel, so there's a separate pin for that.

The UART/SPI/I2C singletons will use the 'default' bus pins for each board - often labeled as RX/TX (UART), MOSI/MISO/SCK (SPI), or SDA/SCL (I2C). Check your board documentation/pinout for the default busses.

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That's all there is to figuring out the available names for a pin on a compatible microcontroller board in CircuitPython!

Microcontroller Pin Names

The pin names available to you in the CircuitPython board module are not the same as the names of the pins on the microcontroller itself. The board pin names are

aliases to the microcontroller pin names. If you look at the datasheet for your microcontroller, you'll likely find a pinout with a series of pin names, such as "PA18" or "GPIO5". If you want to get to the actual microcontroller pin name in CircuitPython, you'll need the microcontroller.pin module. As with board , you can run

dir(microcontroller.pin) in the REPL to receive a list of the microcontroller pin names.

CircuitPython Built-In Modules

There is a set of modules used in most CircuitPython programs. One or more of these modules is always used in projects involving hardware. Often hardware requires installing a separate library from the Adafruit CircuitPython Bundle. But, if you try to find board or digitalio in the same bundle, you'll come up lacking. So, where do these

modules come from? They're built into CircuitPython! You can find an comprehensive list of built-in CircuitPython modules and the technical details of their functionality from CircuitPython here (https://adafru.it/QkB) and the Python-like modules included here (https://adafru.it/QkC). However, not every module is available for every board due to size constraints or hardware limitations. How do you find out what modules are available for your board?

There are two options for this. You can check the support matrix (https://adafru.it/N2a), and search for your board by name. Or, you can use the REPL.

Plug in your board, connect to the serial console and enter the REPL. Type the following command.

help("modules")

That's it! You now know two ways to find all of the modules built into CircuitPython for your compatible microcontroller board.

Advanced Serial Console on Mac and Linux

Connecting to the serial console on Mac and Linux uses essentially the same process. Neither operating system needs drivers installed. On MacOSX, Terminal comes installed. On Linux, there are a variety such as gnome-terminal (called Terminal) or Konsole on KDE.

What's the Port?

First you'll want to find out which serial port your board is using. When you plug your board in to USB on your computer, it connects to a serial port. The port is like a door through which your board can communicate with your computer using USB.

We're going to use Terminal to determine what port the board is using. The easiest way to determine which port the board is using is to first check without the board plugged in. On Mac, open Terminal and type the following:

ls /dev/tty.*

Each serial connection shows up in the /dev/ directory. It has a name that starts with tty. . The command ls shows you a list of items in a directory. You can use * as a

wildcard, to search for files that start with the same letters but end in something different. In this case, we're asking to see all of the listings in /dev/ that start with tty. and

end in anything. This will show us the current serial connections.

For Linux, the procedure is the same, however, the name is slightly different. If you're using Linux, you'll type:

ls /dev/ttyACM*

The concept is the same with Linux. We are asking to see the listings in the /dev/ folder, starting with ttyACM and ending with anything. This will show you the current

serial connections. In the example below, the error is indicating that are no current serial connections starting with ttyACM .

Now, plug your board. Using Mac, type:

ls /dev/tty.*

This will show you the current serial connections, which will now include your board.

Using Mac, a new listing has appeared called /dev/tty.usbmodem141441 . The tty.usbmodem141441 part of this listing is the name the example board is using. Yours will be

called something similar.

Using Linux, type:

ls /dev/ttyACM*

This will show you the current serial connections, which will now include your board.

Using Linux, a new listing has appeared called /dev/ttyACM0 . The ttyACM0 part of this listing is the name the example board is using. Yours will be called something

similar.

Connect with screen

Now that you know the name your board is using, you're ready connect to the serial console. We're going to use a command called screen . The screen command is

included with MacOS. Linux users may need to install it using their package manager. To connect to the serial console, use Terminal. Type the following command, replacing board_name with the name you found your board is using:

screen /dev/tty.board_name 115200

The first part of this establishes using the screen command. The second part tells screen the name of the board you're trying to use. The third part tells screen what baud rate to use for the serial connection. The baud rate is the speed in bits per second that data is sent over the serial connection. In this case, the speed required by the board is 115200 bits per second.

Press enter to run the command. It will open in the same window. If no code is running, the window will be blank. Otherwise, you'll see the output of your code.

Great job! You've connected to the serial console!

Permissions on Linux

If you try to run screen and it doesn't work, then you may be running into an issue with permissions. Linux keeps track of users and groups and what they are allowed to

do and not do, like access the hardware associated with the serial connection for running screen . So if you see something like this:

then you may need to grant yourself access. There are generally two ways you can do this. The first is to just run screen using the sudo command, which temporarily

gives you elevated privileges.

Once you enter your password, you should be in:

The second way is to add yourself to the group associated with the hardware. To figure out what that group is, use the command ls -l as shown below. The group name

is circled in red.

Then use the command adduser to add yourself to that group. You need elevated privileges to do this, so you'll need to use sudo . In the example below, the group is

adm and the user is ackbar.

After you add yourself to the group, you'll need to logout and log back in, or in some cases, reboot your machine. After you log in again, verify that you have been added to the group using the command groups . If you are still not in the group, reboot and check again.

And now you should be able to run screen without using sudo .

And you're in:

The examples above use screen , but you can also use other programs, such as putty or picocom , if you prefer.



Frequently Asked Questions

These are some of the common questions regarding CircuitPython and CircuitPython microcontrollers.

I have to continue using an older version of CircuitPython; where can I find compatible libraries?

We are no longer building or supporting library bundles for older versions of CircuitPython. 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 points to the

last available library bundles for previous versions:

2.x (https://adafru.it/FJA)

3.x (https://adafru.it/FJB)

4.x (https://adafru.it/QDL)

5.x (https://adafru.it/QDJ)

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://learn.adafruit.com/welcome-to-circuitpython/circuitpython-for-esp8266 (https://adafru.it/CiG)

We do not support ESP32 because it does not have native USB. We do support ESP32-S2, which does.



How do I connect to the Internet with CircuitPython?

If you'd like to add WiFi support, check out our guide on ESP32/ESP8266 as a co-processor. (https://adafru.it/Dwa)



Is there asyncio support in CircuitPython?

We do not have asyncio support in CircuitPython at this time. However, async and await are turned on in many builds, and we are looking at how to use event loops

and other constructs effectively and easily.



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 (REPL).

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.

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 https://adafruit-circuit-python.s3.amazonaws.com/index.html?prefix=bin/mpy-cross/ (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?

import gc gc.mem_free()

Will give you the number of bytes available for use.

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/cpy-welcome) CPC = Circuit Playground Classic (https://adafru.it/ncE) CPX = Circuit Playground Express (https://adafru.it/wpF)

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ESP32-S2 Bugs & Limitations

Nobody likes bugs, but all nontrivial software and hardware has some. The master list of problems is the Issues list on github (https://adafru.it/PEk).

Cannot reinitialize certain peripherals (especially busio.I2C)

If you create a busio.I2C object, call .deinit() on it, and then create another one, CircuitPython will lock up.

Workaround: Do not deinitialize I2C objects, except by soft reload or entering deep sleep.

Adafruit considers CircuitPython for the ESP32-S2 to be beta quality software.



No DAC-based audio output

Current versions of esp-idf do not have the required APIs for DAC-based audio output. Once a future version of esp-idf that adds it, it will be possible to implement DAC-based AudioOut in CircuitPython.

Workaround: PWMOut can create tones and buzzes.

Workaround: I2SOut audio is currently being developed and will work with boards such as the Adafruit I2S Stereo Decoder - UDA1334A Breakout (https://adafru.it/PEl).



Deep Sleep & Wake-up sources

ESP32-S2 has hardware limitations on what kind of "pin alarms" can wake it. The following combinations are possible:

EITHER one or two pins that wake from deep sleep when they are pulled LOW OR an arbitrary number of pins that wake from deep sleep when they are pulled HIGH, and optionally one pin that wakes from deep sleep when pulled LOW

This means that "wake" buttons should be wired so that pressing them pulls HIGH and a pull DOWN resistor is used with the pin. However, in some hardware designs including the original MagTag, the integrated buttons are pulled LOW when pressed and so only 1 or 2 buttons can be selected to wake the MagTag.

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.

Always Run the Latest Version of CircuitPython and Libraries

As we continue to develop CircuitPython and create new releases, we 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 (https://adafru.it/ENC).

As we release new versions of CircuitPython, we 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?

We are no longer building or supporting the CircuitPython 5.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)

CPLAYBOOT, TRINKETBOOT, FEATHERBOOT, or GEMMABOOT Drive Not Present

You may have a different board.

Only Adafruit Express boards and the Trinket M0 and Gemma M0 boards ship with the UF2 bootloader (https://adafru.it/zbX)installed. 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

Version 2.5.0.0 or later of the Adafruit Windows Drivers will fix the missing boardnameBOOT drive problem on Windows 7 and 8.1. To resolve this, first uninstall the old

versions of the drivers:

Unplug any boards. In Uninstall or Change a Program (Control Panel->Programs->Uninstall a program) , uninstall everything named "Windows Driver Package Adafruit Industries LLC ...".

We recommend (https://adafru.it/Amd) that you upgrade to Windows 10 if possible; an upgrade is probably still free for you: see the link (https://adafru.it/Amd).



Now install the new 2.5.0.0 (or higher) Adafruit Windows Drivers Package:

https://adafru.it/AB0

When running the installer, you'll be shown a list of drivers to choose from. You can check and uncheck the boxes to choose which drivers to install.

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 boardnameBOOT 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 we know of 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: We have seen 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.

CIRCUITPY Drive Does Not Appear

Kaspersky anti-virus can block the appearance of the CIRCUITPY drive. We haven't yet figured out a settings change 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

https://adafru.it/AB0

Windows can become confused about USB device installations. This is particularly true of Windows 7 and 8.1. We recommend (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 (https://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, 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 sa ve 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 R EPL. 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.

CircuitPython RGB Status Light

Nearly all Adafruit 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.

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 entering the REPL, CircuitPython will set the status LED to WHITE. You can change the status LED color from the REPL. The status indicator will not persist on nonNeoPixel 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

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. WHITE 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.

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 . They are all

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_NAME . These are indicators that your filesystem has issues.

First check - have you used Arduino to program your board? If so, CircuitPython is no longer able to provide the USB services. Reset the board so you get a

boardnameBOOT drive rather than a CIRCUITPY drive, copy the latest version of CircuitPython ( .uf2 ) back to the board, then Reset. This may restore CIRCUITPY

functionality.

If still broken - 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.

In this situation, 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.



Easiest Way: Use storage.erase_filesystem()

Starting with version 2.3.0, CircuitPython includes a built-in function to erase and reformat the filesystem. If you have an older version of CircuitPython on your board, you can update to the newest version (https://adafru.it/Amd) to do this.

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

2. Type:

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

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

Old Way: For the Circuit Playground Express, Feather M0 Express, and Metro M0 Express:

If you can't get to the REPL, or you're running a version of CircuitPython before 2.3.0, and you don't want to upgrade, you can do this.

1. Download the correct erase file:

https://adafru.it/AdI

https://adafru.it/AdJ

https://adafru.it/EVK

https://adafru.it/AdK

https://adafru.it/EoM

https://adafru.it/DjD

https://adafru.it/DBA

https://adafru.it/Eca

https://adafru.it/Gnc

https://adafru.it/GAN

https://adafru.it/GAO

https://adafru.it/Jat

https://adafru.it/Q5B

2. Double-click the reset button on the board to bring up the b oardnameBOOT drive.

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

4. The onboard NeoPixel will turn yellow or blue, indicating the erase has started.

5. After approximately 15 seconds, the mainboard NeoPixel 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 bo ardnameBOOT drive.

https://adafru.it/AdI

https://adafru.it/AdJ

https://adafru.it/EVK

https://adafru.it/AdK

https://adafru.it/EoM

https://adafru.it/DjD

https://adafru.it/DBA

https://adafru.it/Eca

https://adafru.it/Gnc

https://adafru.it/GAN

https://adafru.it/GAO

https://adafru.it/Jat

https://adafru.it/Q5B

7. Drag the appropriate latest release of CircuitPython (https://adafru.it/Amd) .uf2 file to the boardnam eBOOT 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.

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 install your

libraries and code!

Old Way: For Non-Express Boards with a UF2 bootloader (Gemma M0, Trinket M0):

If you can't get to the REPL, or you're running a version of CircuitPython before 2.3.0, and you don't want to upgrade, you can do this.

1. Download the erase file:

https://adafru.it/AdL

2. Double-click the reset button on the board to bring up the b oardnameBOOT drive.

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

4. The boot LED will start flashing again, and the boa rdnameBOOT drive will reappear.

5. Drag the appropriate latest release CircuitPython (https://adafru.it/Amd) .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) You'll also need to install your

libraries and code!

Old Way: For non-Express Boards without a UF2 bootloader (Feather M0 Basic Proto, Feather Adalogger, Arduino Zero):

If you are running a version of CircuitPython before 2.3.0, and you don't want to upgrade, or you can't get to the REPL, you can do this.

Just follow these directions to reload CircuitPython using bossac (https://adafru.it/Bed), which will erase and re-create CIRCUITPY .

Running Out of File Space on Non-Express 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 couple ways to free up space.

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. Its ~12KiB or so.

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.

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, we recommend that 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 we're counting bytes.

MacOS loves to add extra 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

https://adafru.it/AdL

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/CIRCU ITPY cd /Volumes/CIRCUITPY rm -rf .{,_.}{fseventsd,Spot light-V*,Trashes} mkdir .fseventsd touch .fseventsd/no_log .met adata_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()

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 foo.mpy file to the board use a command like:

cp -X foo.mpy /Volumes/C IRCUITPY

(Replace foo.mpy with the name of the file you want to copy.) Or to copy a folder and all of its child files/folders use a command like:

cp -rX folder_to_copy /Volum es/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 foo.mpy /Volumes/CIRCU ITPY/lib # This is safer, and will co mplain if a lib folder does no t exist. cp -X foo.mpy /Volumes/CIRCU ITPY/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 list the amount of space used on the CIRCUITPY

drive with the df command:

Lets remove the ._ files first.

Whoa! We have 13Ki 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. These are not 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 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 following diagram for boot sequence details:

Welcome to the Community!

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. It doesn't matter whether this is your first microcontroller board or you're a computer engineer, you have something important to offer the Adafruit CircuitPython community. We're going to highlight 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-withprojects channel for assistance with your current project or help coming up with ideas for your next one. There's the #showandtell 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.

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. We'd love to hear what you have to say! The #circuitpython 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. We're looking forward to meeting you!

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 and MicroPython (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.

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!

Adafruit Github

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 building CircuitPython. GitHub is the best source of ways to contribute to CircuitPython (https://adafru.it/tB7) itself. 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. Head over to adafruit/circuitpython (https://adafru.it/tB7) on GitHub, click on "Issues (https://adafru.it/Bee)", and you'll find a list that includes issues labeled " good first issue (https://adafru.it/Bef)". These are things we've 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.

Already experienced and looking for a challenge? Checkout the rest of the issues list and you'll find plenty of ways to contribute. You'll find everything from new driver requests to core module updates. There's plenty of opportunities for everyone at any level!

When working with CircuitPython, you may find problems. If you find a bug, that's great! We love bugs! Posting a detailed issue to GitHub is an invaluable way to contribute to improving CircuitPython. 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 current and beta releases is a very important part of contributing CircuitPython. We can't possibly find all the problems ourselves! We need your help to make CircuitPython even better.

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!

ReadTheDocs

ReadTheDocs (https://adafru.it/Beg) is a an excellent resource for a more in depth look at CircuitPython. This is where you'll find things like API documentation and details

about core modules. There is also a Design Guide that includes contribution guidelines for CircuitPython.

RTD gives you access to a low level look at CircuitPython. There are details about each of the core modules (https://adafru.it/Beh). Each module lists the available libraries. Each module library page lists the available parameters and an explanation for each. In many cases, you'll find quick code examples to help you understand how the modules and parameters work, however it won't have detailed explanations like the Learn Guides. If you want help understanding what's going on behind the scenes in any CircuitPython code you're writing, ReadTheDocs is there to help!

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!

LED Location

The build-in red LED (indicated in red in the image) is located in the upp er right of the

FunHouse door, towards the center of the board on the front.

Blinking an LED

Save the following as code.py on your CIRCUITPY drive.

"""CircuitPython Blink Examp le - the CircuitPython 'Hello, World!'""" import time import board import digitalio

led = digitalio.DigitalInOut (board.LED) led.direction = digitalio.Di rection.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.

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 board module, and save it to the variable led . Then, you tell the pin to act as an OUTPUT .

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

time.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.

LED and Button

The red led (indicated by the red box in the image) is located in the upper right of the

FunHouse door, towards the center of the board on the front.

The top button (indicated by the green box in the image) is located near the upper left

corner of the display below the up arrow on the board silk.

Controlling the LED with a Button

Save the following as code.py on your CIRCUITPY drive.

"""CircuitPython Digital Inp ut Example for FunHouse""" import board import digitalio

led = digitalio.DigitalInOut (board.LED) led.direction = digitalio.Di rection.OUTPUT

button = digitalio.DigitalIn Out(board.BUTTON_UP) button.switch_to_input(pull= digitalio.Pull.DOWN)

while True: if not button.value: led.value = False else: led.value = True

Now, press the button. The LED lights up! Let go of the button and the LED turns off.

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.

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!

Built-In DotStar LEDs

Your board has multiple built-in RGB DotStar LEDs. You can use CircuitPython code to control the color and brightness of these LEDs. They are also used to indicate the bootloader status.

A DotStar refers to any 2-wire serial LED, typically APA102, but also possibly SK9822. Along side a driver chip, DotStars have have three LEDs: RGB DotStars have a red LED, a blue LED and a green LED, and white DotStars have three white LEDs. The LEDs on your microcontroller are RGB DotStars! DotStars operate over a generic 2wire SPI bus, which means they aren't as strict about timing. They allow for extremely fast data and PWM rates so they're suitable for POV displays. They can be used individually (as in the built-in LED on your board), or chained together in strips or other creative form factors. DotStars do not light up on their own; they must be connected to a microcontroller. They require two pins, data and clock, to operate. The response time is faster when connected to a hardware SPI pair of pins, but will work connected to any two digital pins. You do not need to worry about connecting the DotStars because they're built into your microcontroller!

This page will cover using CircuitPython to control the RGB DotStars built into your microcontroller. You'll learn how to change the color and brightness, and how to make a rainbow. Time to get started!

DotStar Location

On the FunHouse, the DotStar LE Ds (indicated by red boxes in the ima ge) are spread out

evenly along the top edges of the board, beginning at the top center, and then along the two

edges to the mounting holes.

DotStar Color and Brightness

To use the built-in DotStars on your board, you need to first install the DotStar library into the lib folder on your CIRCUITPY drive.

Then you need to update code.py.

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, and copy the entire lib folder and the code.py file to your CIRCUITPY drive.

"""CircuitPython DotStar red , green, blue example for FunH ouse""" import time import board import adafruit_dotstar

dots = adafruit_dotstar.DotS tar(board.DOTSTAR_CLOCK, board .DOTSTAR_DATA, 5) dots.brightness = 0.3

while True: dots.fill((255, 0, 0)) time.sleep(0.5) dots.fill((0, 255, 0)) time.sleep(0.5) dots.fill((0, 0, 255)) time.sleep(0.5)

Your CIRCUITPY drive contents should resemble the image below.

You should have in / of the CIRCUITPY drive:

code.py

And in the lib folder on your CIRCUITPY drive:

adafruit_bus_device/

adafruit_dotstar.mpy

adafruit_pixelbuf.mpy

The DotStar LEDs being flashing red, green and blue!

First you import the necessary modules, time and board , and the necessary library, adafruit_dotstar . This makes these modules and libraries available for use in your

code. The first two are modules built-in to CircuitPython, so you don't need to download anything to use those. The adafruit_dotstar library is separate, which is why you

needed to install it before getting started.

Next, you set up the Dotstar LEDs. 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 adafruit_dotstar.DotStar() object, provide it the DotStar LED pins using the board module, and tell it the number of LEDs. You save this object to the

variable pixels .

Then, you set the DotStar brightness using the brightness attribute. brightness expects float between 0 and 1.0 . A

float

is essentially a number with a decimal in it. The

brightness value represents a percentage of maximum brightness; 0 is 0% and 1.0 is 100%. Therefore, setting pixel.brightness = 0.3 sets the brightness to 30%. The

default brightness, which is to say the brightness if you don't explicitly set it, is 1.0 . The default is really bright! That is why there is an option available to easily change

the brightness.

Inside the loop, you turn the DotStars red for 0.5 seconds, green for 0.5 seconds, and blue for 0.5 seconds.

To turn the DotStars red, you "fill" them with an RGB value. Check out the section below for details on RGB colors. The RGB value for red is (255, 0, 0) . Note that the RGB

value includes the parentheses. The fill() attribute expects the full RGB value including those parentheses. That is why there are two pairs of parentheses in the code.

You can change the RGB values to change the colors that the DotStars cycle through. Check out the list below for some examples. You can make any color of the rainbow with the right RGB value combination!

That's all there is to changing the color and setting the brightness of the built-in DotStar LEDs!

RGB LED Colors

RGB LED colors are set using a combination of red, green, and blue, in the form of an (R, G, B) tuple. Each member of the tuple is set to a number between 0 and 255 that determines the amount of each color present. Red, green and blue in different combinations can create all the colors in the rainbow! So, for example, to set an LED to red, the tuple would be (255, 0, 0) , which has the maximum level of red, and no green or blue. Green would be (0, 255, 0) , etc. For the colors between, you set a

combination, such as cyan which is (0, 255, 255) , with equal amounts of green and blue. If you increase all values to the same level, you get white! If you decrease all the

values to 0, you turn the LED off.

Common colors include:

If your DotStars do not start flashing red, green and blue, make sure you've copied all the necessary files and folders to the CIRCUITPY drive!



red: (255, 0, 0)

green: (0, 255, 0)

blue: (0, 0, 255)

cyan: (0, 255, 255)

purple: (255, 0, 255)

yellow: (255, 255, 0)

white: (255, 255, 255)

black (off): (0, 0, 0)

DotStar Rainbow

You should have already installed the library necessary to use the built-in DotStar LEDs. If not, follow the steps at the beginning of the DotStar Color and Brightness section to install it.

Update your code.py to the following, and save.

"""CircuitPython DotStar rai nbow example for FunHouse""" import time import board import adafruit_dotstar from rainbowio import colorw heel

dots = adafruit_dotstar.DotS tar(board.DOTSTAR_CLOCK, board .DOTSTAR_DATA, 5, auto_write=Fa lse) dots.brightness = 0.3

def rainbow(delay): for color_value in range (255): for led in range(5): pixel_index = (l ed * 256 // 5) + color_value dots[led] = colo rwheel(pixel_index & 255) dots.show() time.sleep(delay)

while True: rainbow(0.01)

The DotStars display a rainbow cycle!

This example builds on the previous example.

First, you import the same three modules and libraries. In addition to those, you import colorwheel .

The DotStar hardware setup is similar, but you now also set auto_write to False . This means that now the DotStar won't change unless you explicitly tell it to by calling

show() . This is necessary for this example to speed up the rainbow animation. Brightness setting is the same.

Next, you have the rainbow() helper function. This helper displays the rainbow cycle. It expects a delay in seconds. The higher the number of seconds provided for

delay , the slower the rainbow will cycle. The helper cycles through the values of the color wheel to create a rainbow of colors.

Inside the loop, you call the rainbow helper with a 0.01 second delay, by including rainbow(0.01) .

That's all there is to making rainbows using the built-in DotStar LEDs!

CPU Temperature

There is a temperature sensor built into the CPU on your microcontroller board. It reads the internal CPU temperature, which varies depending on how long the board has been running or how intense your code is.

CircuitPython makes it really simple to read this data from the temperature sensor built into the microcontroller. Using the built-in microcontroller module, you can easily

read the temperature.

Microcontroller Location

The microcontroller on the FunHo use is located on the bottom of the b ack of the board,

towards the center.

Reading the Microcontroller Temperature

The data is read using two lines of code. All necessary modules are built into CircuitPython, so you don't need to download any extra files to get started.

Connect to the serial console (https://adafru.it/Bec), and then update your code.py to the following and save.

"""CircuitPython CPU tempera ture example in Celsius""" import time import microcontroller

while True: print(microcontroller.cp u.temperature) time.sleep(0.15)

The CPU temperature in Celsius is printed out to the serial console!

Try putting your finger on the microcontroller to see the temperature change.

The code is simple. First you import two modules: time and microcontroller . Then, inside the loop, you print the microcontroller CPU temperature, and the time.sleep()

slows down the print enough to be readable. That's it!

You can easily print out the temperature in Fahrenheit by adding a little math to your code, using this simple formula: Celsius * (9/5) + 32.

Update your code.py to the following, and save.

"""CircuitPython CPU tempera ture example in Fahrenheit""" import time import microcontroller

while True: print(microcontroller.cp u.temperature * (9 / 5) + 32) time.sleep(0.15)

The CPU temperature in Fahrenheit is printed out to the serial console!

That's all there is to reading the CPU temperature using CircuitPython!

Arduino IDE Setup

The first thing you will need to do is to download the latest release of the Arduino IDE. You will need to be using version 1.8 or higher for this guide

https://adafru.it/f1P

The ESP32-S2 Arduino board support package is currently part of the 2.0.0-alpha1 release. To use the ESP32-S2 with Arduino, you'll need to follow the steps below for your operating system. You can also check out the Espressif Arduino repository for the most up to date details on how to install it (https://adafru.it/weF).

After you have downloaded and installed the latest version of Arduino IDE , you will need to start the IDE and navigate to the Preferences menu. You can access it from the File menu in

Windows

Linux

, or the Arduino menu on

OS X

A dialog will pop up just like the one shown below.

We will be adding a URL to the new Additional Boards Manager URLs option. The list of URLs is comma separated, and

you will only have to add each URL once.

New Adafruit boards and updates to existing boards will automatically be picked up by the Board Manager each time it is opened. The URLs point to index files that the Board Manager uses to build the list of available & installed boards.

To find the most up to date list of URLs you can add, you can visit the list of third party board URLs on the Arduino IDE wiki (https://adafru.it/f7U). We will only need to add one URL to the IDE in this example, but

you can add multiple URLS by separating them with commas

. Copy and paste the link below into the Additional Boards

Manager URLs option in the Arduino IDE preferences.

https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_dev_index.json

https://adafru.it/f1P

If you have multiple boards you want to support, say ESP8266 and Adafruit, have both URLs in the text box separated by a comma (,)

Once done click OK to save the new preference settings.

In the Tools → Board submenu you should see ESP32 Arduino and in that dropdown it should contain the ESP32 boards along with all the latest ESP32-S2 boards.

Look for the board called Adafruit FunHouse.

Arduino Libraries

OK now that you have Arduino IDE set up, drivers installed if necessary and you've practiced uploading code, you can start installing all the Libraries we'll be using to program it.

There's a lot of libraries!

Install Libraries

Open up the library manager...

And install the following libraries:

Adafruit DotStar

This will let you light up the status LEDs on the front

Adafruit GFX

This is the graphics library used to draw to the screen

If using an older (pre-1.8.10) Arduino IDE, locate and install Adafruit_BusIO (newer versions do this automatically when installing Adafruit_GFX).

Adafruit ST7735 and ST7789

For using the display.

Adafruit ImageReader

For reading bitmaps from SD and displaying

Adafruit AHTX0

For using the Humidity and Temperature Sensor

Adafruit DPS310

For using the Pressure Sensor

Arduino Basics

Once you have Arduino installed and set up and you can upload simple blink sketches, you can move on to using each element of the FunHouse board.

Using the Red LED

It's always good to blink the LED when you want to verify if something is happening on your board. The LED is on IO #13, but we recommend you use the

LED_BUILTIN macro and you can use this simple sketch example to blink the LED:

void setup() { // initialize built in LED pin as an output. pinMode(LED_BUILTIN, OUTPU T); // initialize USB serial c onverter so we have a port cre ated Serial.begin(); }

// the loop function runs ov er and over again forever void loop() { digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (H IGH is the voltage level) delay(1000); // wait for a second digitalWrite(LED_BUILTIN, LOW); // turn the LED off b y making the voltage LOW delay(1000); // wait for a second }

Reading the Buttons

There are three buttons on the front of the FunHouse - they're connected to digital pins IO 3, 4, and 5. However, we recommend you use the constants BUTTON_DOWN

BUTTON_SELECT , BUTTON_UP .

void setup() { Serial.begin(115200);

pinMode(BUTTON_DOWN, INPUT _PULLDOWN); pinMode(BUTTON_SELECT, INP UT_PULLDOWN); pinMode(BUTTON_UP, INPUT_P ULLDOWN); }

void loop() { if (digitalRead(BUTTON_DOW N)) { Serial.println("Down But ton pressed"); } if (digitalRead(BUTTON_SEL ECT)) { Serial.println("Select B utton pressed"); } if (digitalRead(BUTTON_UP) ) { Serial.println("Up Butto n pressed"); }

// small debugging delay delay(10); }

Open the serial console and press buttons to see the serial output printed!

Arduino support for the ESP32-S2 is relatively new right now, so we recommend using CircuitPython!



Reading the Capacitive Touch Pads

To read the value of the capacitive touch pads, you can use the touchRead() function, which is part of the ESP32 package. To use it, you only need to provide the GPIO

pin number. The FunHouse uses IO #6, #7, and #8 for the button style touch pads and #9 through #13 along the slider.

So to get the value of IO #7, you would use the following code:

uint16_t touchread;

touchread = touchRead(7); if (touchread > 20000 ) { // Do Something }

You may want to try adjusting the threshold for your needs. A more complete example can be found on the Arduino Self Test Example page.

Using On-Board DotStars

There are 4 DotStar LEDs on pin IO #14 and #15 (we recommend using the macro PIN_DOTSTAR_DATA and PIN_DOTSTAR_CLOCK ).

Here's an example sketch that initializes the DotStar LEDs and color cycles them through a rainbow of different colors.

#include <Adafruit_DotStar.h >

#define NUM_DOTSTAR 5

// LEDs! Adafruit_DotStar pixels(NUM_ DOTSTAR, PIN_DOTSTAR_DATA, PIN _DOTSTAR_CLOCK, DOTSTAR_BRG);

uint16_t firstPixelHue = 0; uint8_t LED_dutycycle = 0;

void setup() { Serial.begin(115200);

pinMode(LED_BUILTIN, OUTPU T);

ledcSetup(0, 5000, 8); ledcAttachPin(LED_BUILTIN, 0);

pixels.begin(); // Initial ize pins for output pixels.show(); // Turn al l LEDs off ASAP pixels.setBrightness(20); }

void loop() { Serial.println("Hello!");

// pulse red LED ledcWrite(0, LED_dutycycle ++);

// rainbow dotstars for (int i=0; i<pixels.num Pixels(); i++) { // For each p ixel in strip... int pixelHue = firstPi xelHue + (i * 65536L / pixels. numPixels()); pixels.setPixelColor(i , pixels.gamma32(pixels.ColorH SV(pixelHue))); } pixels.show(); // Update s trip with new contents firstPixelHue += 256;

delay(15); }

void rainbow(int wait) { for(long firstPixelHue = 0 ; firstPixelHue < 5*65536; fir stPixelHue += 256) { for(int i=0; i<pixels.nu mPixels(); i++) { // For each pixel in strip... int pixelHue = firstPi xelHue + (i * 65536L / pixels. numPixels()); pixels.setPixelColor(i , pixels.gamma32(pixels.ColorH SV(pixelHue))); } pixels.show(); // Update strip with new contents delay(wait); // Pause f or a moment } }

Using On-board Humidity and Temperature Sensor

There's a pre-soldered humidity and temperature sensor that you can use.

You can test the AHTX0 by loading the included adafruit_aht_test in the Arduino library

Now you can upload, reset, and check the serial port for temperature and humidity data!

Using On-board Pressure Sensor

There's a pre-soldered pressure sensor that you can use.

You can test the DPS310 by loading the included adafruit_sensor_test in the Arduino library

Now you can upload, reset, and check the serial port for ambient temperature and pressure data!

Using the TFT Display

You've been so patient, it's time to draw to the display!

We'll be using a demo that was written for the HalloWing M4, which has the same display, so only a couple of minor changes are needed.

From the Adafruit ST7735 and ST7789 Library folder, open the graphicstest_hallowing_m4 example

Remove the pin definitions near the top since they are now part of the FunHouse Board Support Package.

#define TFT_CS 44 // PyBadge/PyGamer display contro l pins: chip select #define TFT_RST 46 // Display reset #define TFT_DC 45 // Display data/command select #define TFT_BACKLIGHT 47 // Display backlight pin

Change the initialization line to the following:

Adafruit_ST7789 tft = Adafru it_ST7789(TFT_CS, TFT_DC, TFT_ RESET);

You can now upload the example to your FunHouse to see it display various graphics and text tests.

For more information on how to display graphics, and text, check out the Adafruit GFX guide (https://adafru.it/doL)

Adafruit FunHouse User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual