{"id":7745,"date":"2021-03-05T08:59:53","date_gmt":"2021-03-05T13:59:53","guid":{"rendered":"https:\/\/dronebotworkshop.com\/?p=7745"},"modified":"2023-04-12T09:18:41","modified_gmt":"2023-04-12T13:18:41","slug":"pi-pico-circuitpython","status":"publish","type":"post","link":"https:\/\/dronebotworkshop.com\/pi-pico-circuitpython\/","title":{"rendered":"Raspberry Pi Pico with CircuitPython"},"content":{"rendered":"\n

\"Download \"Parts<\/a> \"View<\/a> \"Download<\/a><\/p>\n

Today we\u2019ll take a look at CircuitPython, another way to program the Raspberry Pi Pico.\u00a0 We\u2019ll see how we can take advantage of Adafruit’s large base of CircuitPython libraries to build some great projects with our Pico.<\/span><\/p>\n

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If you aren\u2019t familiar with the Pico please see my article <\/span>Raspberry Pi Pico \u2013 How to Interface (almost) Everything<\/span><\/i><\/a> to get all caught up.<\/span><\/p>\n

Introduction<\/span><\/h2>\n

I\u2019m writing this article about a month after the introduction of the Raspberry Pi Pico. It\u2019s an important point to make note of, because as of this writing the Pico is the only RP2040-based board available.\u00a0<\/span><\/p>\n

Because of the \u201cnewness\u201d of the Raspberry Pi Pico, there is a lack of MicroPython software examples and no support (yet) for C++ development on popular IDEs like the Arduino IDE or PlatformIO.<\/span><\/p>\n

This situation will obviously be changing very soon, with new boards from Adafruit, Sparkfun, and Arduino which should be released shortly.\u00a0 With these boards will come more sample code and libraries for both C++ and MicroPython.\u00a0 And with Arduino’s involvement, we should also see support for C++ development on our favorite IDEs.<\/span><\/p>\n

But right now we have this wonderful microcontroller and would like to start building things with it to exploit its unique capabilities.<\/span><\/p>\n

CircuitPython provides us with the ability to do this right now.<\/span><\/p>\n

CircuitPython<\/span><\/h2>\n

CircuitPython<\/a> is a \u201cfork\u201d of MicroPython and was first published by Adafruit in 2017.\u00a0\u00a0<\/span><\/p>\n

\"CircuitPython<\/p>\n

Originally CircuitPython was only available for Adafruit SAMD21 (M0) boards, but it has grown to support over 175 boards from a number of different manufacturers.<\/span><\/p>\n

Although CircuitPython lacks some of the features of MicroPython it has some advantages. One of the biggest advantages is the availability of libraries and drivers for a variety of boards and peripherals, as of this writing, there are over 300 of these available. Also, by making use of the Adafruit Blinka library you can also access virtually any Python 3 library.<\/span><\/p>\n

CircuitPython is particularly great for beginners, as code in CircuitPython all run sequentially and multiple files are run one at a time. This lack of concurrency will cause issues with some more advanced applications, and combined with the lack of support for interrupts will make CircuitPython unsuitable for some applications.<\/span><\/p>\n

But if you\u2019re looking for an easy-to-use development language with a wealth of libraries and code samples it\u2019s hard to beat.<\/span><\/p>\n

Consider it as one more tool that you can use to build things with the Pico and other microcontrollers.<\/span><\/p>\n

Installing CircuitPython on the Raspberry Pi Pico<\/span><\/h2>\n

Of course, the first thing you\u2019ll need to do to start working with CircuitPython is to install it on your Pico. This is pretty easy.<\/span><\/p>\n

Downloading CircuitPython<\/span><\/h3>\n

You can get the latest build of CircuitPython from the <\/span>download page on the CircuitPython website<\/span><\/a>.<\/span><\/p>\n

The file you are downloading is a UF2 boot file, when mounted into the boot folder on the Pico it will start and load CircuitPython.<\/span><\/p>\n

\"Raspberry<\/p>\n

Let\u2019s do that now.<\/span><\/p>\n

Reset and BOOTSEL<\/span><\/h3>\n

In order to open up the Pico as a drive, you need to hold down the BOOTSEL key while plugging in the Pico USB cable. You\u2019ll then be prompted about a new drive on your machine called \u201cRPI-RP2\u201d, this is the Pico \u201cdrive\u201d that we will require to install CircuitPython.<\/span><\/p>\n

Another way of accomplishing the same thing, without the need to unplug and plug in the USB cable, is by holding the Pico RUN pin (pin # 30) to ground , then pressing BOOTSEL and holding it down, releasing the RUN connection to Ground and then releasing BOOTSEL.<\/span><\/p>\n

You can wire a pushbutton switch between pin 30 and Ground to make this easier, essentially you have just added a \u201cReset\u201d key to your Pico.<\/span><\/p>\n

\"Raspberry<\/p>\n

Hold down \u201cReset\u201d, keep it held down while holding down BOOTSEL, release Reset and then release BOOTSEL. You will see a RPI-RP2 \u201cdrive\u201d added to your host computer.<\/span><\/p>\n

CircuitPython Installation<\/span><\/h3>\n

Installing CircuitPython is simply a matter of copying the UF2 file you downloaded into the RPI-RP2 drive. The easiest way to do this is to drag the UF@ file into the RPI-RP2 folder.<\/span><\/p>\n

As soon as the file is finished copying the RPI-RP2 drive will be ejected. After about a second a new drive will be mounted. This drive is called CIRCUITPY.<\/span><\/p>\n

Testing the CircuitPython Installation<\/span><\/h2>\n

If you have a CIRCUITPY folder then you have probably succeeded in your task, and have installed CircuitPython on your Raspberry Pi Pico.\u00a0 Let’s poke around and give it a test drive.<\/span><\/p>\n

\"Raspberry<\/p>\n

CircuitPython Folder<\/span><\/h3>\n

When you plug your Pico into your host computer you\u2019ll be greeted by a folder called CIRCUITPY. This is the folder that holds CircuitPython on your Raspberry Pi Pico.<\/span><\/p>\n

You can only keep a maximum of about a megabyte in here, so don\u2019t start storing non-essential files. Only the code, data, and library files that you need should be kept here.<\/span><\/p>\n

You will see a folder labeled \u201c<\/span>lib<\/span><\/i>\u201d, this is your Library folder. We will be copying a few libraries into this folder a bit later.<\/span><\/p>\n

You\u2019ll also see two files:<\/span><\/p>\n