Raspberry Pi Pico

128 Articles

PicoMite Gives Your Pico A Deluxe BASIC

November 24, 2021 by 57 Comments

What makes developing a microcontroller project quick and easy? Tops on our list are an interactive shell and comprehensive libraries that handle all the low-level peripheral stuff. You think we’re talking MicroPython? Not today! MMBasic has just been ported to the Raspberry Pi Pico dev board, and it has all the batteries included.

Just to give you a taste, it has built-in support for SD cards, all sorts of displays, touch screens, real-time clocks, IR remotes, numerous sensors, and of course WS2812 LED strips. And because all of this is baked into the BASIC, writing code to use any of these peripherals is straightforward.

Now, there’s BASIC and there’s BASIC. This is a modern BASIC: it has loops, functions, arrays, floating point, and a built-in full-screen editor. You connect to the Pico via UART, and you’re off to the races. If you’ve got a Pico sitting around, flash it and give it a try. Or check out the GitHub repository if you want to poke around in the internals.

This is a port of the BASIC that’s used on the Maximite virtual retrocomputer platform, which means that there are many working examples out there for you to crib from, and even a forum. Add in the incredibly nice user manual and tutorial (PDF), and you’ve got the perfect weekend afternoon.

Think MicroPython killed BASIC? Think again. BASIC is small enough that it can run where Python can’t, but that’s of course a more minimal experience. In contrast, MMBasic looks like it’s got all the toppings. The whole enchilada. It’s like BASIC Deluxe.

A conventiongoer plays Pokemon on a working Color Game Boy costume.

Convention Plays Pokemon On Giant Color Game Boy Costume

September 29, 2021 by 2 Comments

Standard cosplay is fun and all, but what is there for admirers to do but look you up and down and nitpick the details? Interactive cosplay, now that’s where it’s at. [Jaryd Giesen] knows this, and managed to pull together a working color Game Boy costume in a few days.

The original plan was to use a small projector on an arm, like one of those worm lights that helped you see the screen, but [Jaryd] ended up getting a secondhand monitor and strapping it to his chest. Then he took the rest of the build from there. Things are pretty simple underneath all that cardboard: there’s a Raspberry Pi running the RetroPie emulator, a Pico to handle the inputs, and two batteries — one beefy 12,000 mAH battery for the monitor, and a regular power pack for the Pi and the Pico.

As you’ll see in the build and demo video after the break, nearly 100 people stopped to push [Jaryd]’s buttons. They didn’t get very far in the game, but it sure looks like they had fun trying.

Since we’re still in a pandemic, you may want to consider incorporating a mask into your Halloween costume this year. Just a thought.

Continue reading “Convention Plays Pokemon On Giant Color Game Boy Costume” →

Raspberry Pi Pico Used As A Transputer

August 5, 2021 by 43 Comments

You can’t fake that feeling when a $4 microcontroller dev board can stand in as cutting-edge 1980s technology. Such is the case with the working transputer that [Amen] has built using a Raspberry Pi Pico.

For a thorough overview of the transputer you should check out [Jenny List’s] longer article on the topic but boiled down we’re talking about a chip architecture mostly forgotten in time. Targetting parallel computing, each transputer chip has four serial communication links for connecting to other transputers. [Amen] has wanted to play with the architecture since its inception. It was expensive back then and today, finding multiple transputers is both difficult and costly. However, the RP2040 chip found on the Raspberry Pi Pico struck him as the perfect way to emulate the transputer design.

The RP2040 chip on the Pico board has two programmable input/output blocks (PIOs), each with four state machines in them. That matches up perfectly with the four transputer links (each is bi-directional so you need eight state machines). Furthermore, the link speed is spec’d at 10 MHz which is well within the Pico’s capabilities, and since the RP2040 runs at 133 MHz, it’s conceivable that an emulated core can get close to the 20 MHz top speed of the original transputers.

Bringing up the hardware has been a success. To see what’s actually going on, [Amen] sourced some link adapter chips (IMSC011), interfacing them through an Arduino Mega to a computer to use the keyboard and display. The transputer architecture allows code to be loaded via a ROM, or through the links. The latter is what’s running now. Future plans are to figure out a better system to compile code, as right now the only way is by running the original INMOS compiler on DOS in a VM.

Listen to [Amen] explain the project in the first of a (so far) six video series. You can find the links to the rest of those videos on his YouTube channel.

Continue reading “Raspberry Pi Pico Used As A Transputer” →

New Video Series: Raspberry Pi Pico And RP2040 Deep Dive With Uri Shaked

July 29, 2021 by 15 Comments

In case you’ve been living under a rock that doesn’t have internet access, the Raspberry Pi Foundation got into the silicon sales and microcontroller game all at once this year with the Raspberry Pi Pico. It’s small, it’s capable, and it costs a measly $4. Surely you have one or two of them by now, right? But how much do you know about what it can do?

Or maybe you don’t have one yet, but it’s on your list. In either case, you can get started learning about them right away because [Uri Shaked]’s Raspberry Pi Pico and RP2040 Deep Dive course has recently been freed from the hallowed halls of HackadayU. He even built an emulator to go with it. [Uri] is a great instructor, and we’re sure that goes double if you ever need a salsa dance teacher, which he has also mastered.

This class was held for five weeks beginning in May 2021, with each session being roughly an hour long. The only prerequisite is a basic understanding of bitwise math, but there are resources for that on the class IO page linked above.

Each class is incredibly well-organized and informative. In the first class, [Uri] begins building a living document that includes the class agenda, links to all resources used and mentioned, code examples, and assembly instructions where applicable. It’s basically a syllabus plus a whole lot more. [Uri] also spends a lot of time in the incredibly thorough 649-page data sheet for the RP2040, and a little bit of time in the much shorter Getting Started guide. If you think the data sheet is inaccessible, you’ll likely change your tune by the end of the first class after you’ve seen [Uri] use and peruse it.

Continue reading “New Video Series: Raspberry Pi Pico And RP2040 Deep Dive With Uri Shaked” →

Raspberry Pi Pico Oscilloscope

June 26, 2021 by 50 Comments

As you dive deeper into the world of electronics, a good oscilloscope quickly is an indispensable tool. However, for many use cases where you’re debugging low voltage, low speed circuits, that expensive oscilloscope is using only a fraction of its capabilities. As a minimalist alternative for these use cases [fhdm-dev] created Scoppy, a combination of firmware for the Raspberry Pi Pico and an Android app to create a functional oscilloscope.

As you would expect, the specifications are rather limited, capturing a maximum of 100 kpts at a speed of 500 kS/s shared between the two channels. Without some additional front end circuitry to protect the Pico, the input voltage is limited to 0-3.3 V. Neither the app nor the firmware is open source, and getting access to the second channel and removing ads requires a ~$3 in-app purchase. Even so, we can still think of plenty of practical uses for a ~$7 oscilloscope. If you do decide to add some front-end circuitry to change to voltage range, you can set them in the app, and switch between them by pulling certain GPIO pins high or low. The app has most of the basic oscilloscope features covered, continuous and single shot capture, adjustable trigger settings and a scalable waveform display.

Simple, cheap oscilloscopes like these have their place, but you start to understand why the “real” ones are so expensive when you see what goes into developing a high performance oscilloscope.

VGA Library For The Raspberry Pi Pico

June 11, 2021 by 11 Comments

[Miroslav Nemecek] really pushes the limits of the Pico with his PicoVGA project, which packs a surprising number of features. His main goal with this library is to run retro games which can fit within the limited RAM and processing power of the Pico, but the demo video below shows a wide array of potential applications.

The library provides a whole slew of features, including frame buffering, sprites, overlays, and resolutions up to 1280×960 in either NTSC or PAL timings. A PWM-driven audio output channel is also included in the package. His library takes full advantage of the programmable I/O module functionality and uses the second core which is dedicated to video processing. However, with care, the second core can perform application tasks in certain circumstances. The VGA analog output signals are provided by resistor ladders, and pixel color is 8-bit R3G3B2 format. To be clear, [Miroslav] does cheat a little bit here in one regard — he overclocks the processor up to 270 MHz to meet the timing demands in some of the resolutions.

[Miroslav] has developed these tools using ARM-GCC on Windows, but he lacks the experience to make a Linux build. He welcomes help on that front from anyone familiar with Linux. And stay tuned — there may be more coming from [Miroslav] in the future. He notes that the PicoVGA library was created as part of a retro gaming computer project which is still under development. We look forward to hearing more about this when it gets released.

A couple of weeks ago we wrote about a monochrome VGA version of Pong for the Pico by [Nick Bild]. It’s exciting to see these projects which are exploring the limits of the Pico’s capabilities. Have you seen any boundary-pushing applications for the Pico? Let us know in the comments below. Thanks to [Pavel Krivanek] for sending this project to our tip line.

Continue reading “VGA Library For The Raspberry Pi Pico” →

Tiny Mechanical Keyboard, Powered By Pi Pico

June 9, 2021 by 18 Comments

For some applications, smaller is better and that is precisely the thinking behind a diminutive keyboard like the PiPi Gherkin, which is designed to use the Raspberry Pi Pico as its controller. This keyboard may have only 30 keys in total, but they are full-sized for comfort and don’t let the scant layout mislead you. It has more functionality than it would seem to at first glance; the entire bottom row acts as dual function tap/hold keys, allowing the keyboard to shift layers on the fly.

This keyboard definitely has a a thoughtful layout, and we’re not just talking about the tap/shift functionality. We especially like the way the Pi Pico is tucked neatly underneath the main PCB, taking up very little room while exposing its USB connector between two standoffs for easy access without requiring an adapter, or wiring a separate plug.

If the Gherkin sounds familiar, we’ve seen it before as part of this lunchbox cyberdeck build, where the small size allowed it to take up impressively little room. The shifting might take a little getting used to, but it’s a clean design that uses full sized keys, so when it comes to small keyboards one could certainly do worse.