Raspberry Pi Cookbook, 4th Edition

Chapter 19. Raspberry Pi Pico and Pico W

19.0 Introduction

Although a regular Raspberry Pi is ideal for projects that need a network connection or a graphical user interface (GUI), its power consumption and lack of any analog inputs puts it at a disadvantage to a simpler microcontroller board such as the Arduino or Raspberry Pi Pico.

The Raspberry Pi Pico is very different from any other Raspberry Pi in several ways:

• It doesn’t have any interface to keyboard, mouse, or screen.

• It has a relatively small 2M of flash memory for storing programs (no microSD slot) and 264k of RAM.

• Its processor runs at just 133 MHz, compared with the Raspberry Pi 4’s 1.2 GHz.

• It doesn’t have an operating system. In effect, MicroPython is its operating system, and you just get what you see when you’re on the Python command line.

This might lead you to wonder why you would use such an apparently feeble board rather than, say, a Raspberry Pi Zero.

The answer is that the Pico (Figure 19-1) is even lower cost than a Pi Zero and better than a Raspberry Pi 4 at interfacing with external electronics in several ways. For example:

• Three analog inputs makes connecting analog sensors much easier than with a regular Raspberry Pi.

• Six pulse-width modulation (PWM) outputs. These outputs are hardware-timed and produce a much more accurate PWM signal than can be achieved with the Raspberry Pi, making them a lot better for controlling servomotors.

• Built-in power supply that allows the Pico to be powered ...