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Raspberry Pi Pico

In the past we have look at various things that can be done with a Raspberry Pi computer, these matchbox sized computers
have increased in power and features over the last few years. If you just want a computer to browse the internet you can set
one up very quickly which will allow you access to the internet at a very reasonable price.

The manufactures have now gone in the opposite direction and produced a new version which looks to be intended for
dedicated small projects

The Raspberry Pi Pico is a big change from previous Pi’s, because it’s not a Linux computer, but a microcontroller
board like Arduino . The biggest selling points of the Raspberry Pi Pico are the price, under £4.00 and the new
RP2040 chip which provides ample power for embedded projects and enables users of any age or ability to learn
coding and electronics. If you have a Windows, Apple, Linux computer or even a different Raspberry Pi, then you
are already well on your way to using the Raspberry Pi Pico in your next project.

The Raspberry Pi Pico is vastly different to any model before it. It is the first device to use RP2040 “Pi Silicon”
which is a custom System on Chip (SoC) developed by the Raspberry Pi team which features a dual core Arm Cortex
M0+ running at 133 MHz, 264KB of SRAM and 2MB of flash memory used to store files.

The one downside of the Raspberry Pi Pico is that there is no wireless connectivity. The RP2040 is the first micro-
controller in the Pi range and this brings with it a new way of working. The Pico is not a computer, so you need to
write code in an external application on a different computer and “flash” the code to the microcontroller over USB.

Writing code for the Raspberry Pi Pico is handled in C/C++ or MicroPython, the latter being the officially supported
language for general and education use.

MicroPython is a version of Python 3 for microcontrollers. It was created back in 2014 and first used with the Py-
Board development board.

A version of MicroPython, CircuitPython has been released for RP2040 boards and has an impressive library of pre-
written modules for sensors, LCD / OLED / LED screens and output devices such as thermal printers. Flashing Cir-
cuitPython to the Raspberry Pi Pico is as simple as flashing MicroPython, and it is reversible should you wish to re-
vert back to MicroPython or C/C++.

Writing code in C/C++ is made possible via two methods. Firstly you can write the code directly in a text editor of
our choice and then follow a workflow to build the files which are then flashed to the Pico. Or you can use a graph-
ical workflow and have Microsoft’s Visual Studio Code handle the creation, build and flash process in one applica-
tion.

Operating at 3.3V, the Raspberry Pi Pico has a 40 pin GPIO, but it does not share the same form factor as the Rasp-
berry Pi’s before it. We have GPIO pins for digital inputs / outputs, pulse width modulation (PWM) and for specialist
communication protocols such as I2C, SPI, UART/Serial. The GPIO also has three Analog inputs, something other