pico

37 Articles

Raspberry Pi Pico W Adds Wireless

June 30, 2022 by 63 Comments

News just in from the folks at Raspberry Pi: the newest version of their Pico has WiFi and is called, obviously, the Pico W. We were going to get our hands on a sample unit and kick its tires, but it’s stuck in customs. Boo! So until it shows up, here’s what we can glean from the press releases and documentation.

The Pico is, of course, the Raspberry Pi microcontroller dev board based on their RP2040 microcontroller. This in turn has two Cortex M0+ cores and a good chunk of onboard RAM, which has made it a popular target for MicroPython. They had some extra real estate on the PCB, so they’ve added an Infineon CYW43439 WiFi chip, and voila: Pico W.

As of now, the WiFi is supported in both the C SDK and the pre-baked MicroPython image. It looks trivially easy to get it working, and it’s based on the time-tested lwIP stack, a classic in the embedded world. The CYW43439 is also Bluetooth capable, but there’s no firmware support for that yet, but we wouldn’t be surprised if it showed up soon.

The price? $6 for the whole shooting match. You can view this two ways: a small $2 premium over the old Pico, or a price increase of 50%. How you see things probably depends on your order quantity. Either way, it’s firmly in the ESP32 module price range, so you’ve got some comparison shopping to do if your project needs a microcontroller and WiFi. And in these days of silicon shortages, it’s nice to have a couple of options.

A Pi Pico connected to a MYIR Z-turn board with a set of jumper wires

Need A JTAG Adapter? Use Your Pico!

April 11, 2022 by 9 Comments

JTAG is a powerful interface for low-level debugging and introspection of all kinds of devices — CPUs, FPGAs, MCUs and a whole lot of complex purpose-built chips like RF front-ends. JTAG adapters can be quite obscure, or cost a pretty penny, which is why we’re glad to see that [Adam Taylor] from [ADIUVO] made a tutorial on using your Pi Pico board as a JTAG adapter. This relies on a project called XVC-Pico by [Dhiru Kholia], and doesn’t require anything other than a Pi Pico board itself — the XVC-Pico provides both a RP2040 firmware implementing the XVC (Xilinx Virtual Cable) specification and a daemon that connects to the Pico board and interfaces to tools like Vivado.

First part of the write-up is dedicated to compiling the Pico firmware using a Linux VM. There’s a pre-built .uf2 binary available in the GitHub repo, however, so you don’t have to do that. Then, he compiles and runs a daemon on the PC where the Pico is connected, connects to that daemon through Vivado, and shows successful single-stepping through code on a MYIR Z-turn board with a Xilinx XC7Z020. It’s worth remembering that, if your FPGA’s (or any other target’s) JTAG logic levels are 1.8V or 2.5V-based, you will need a level shifter between it and the Pi Pico, which is a board firmly in the 3.3V realm.

You just cannot beat the $3 price and the ease of setup. Pi Pico is shaping up to be more and more of a hardware multi-tool. Just a month ago, we covered how the Pico can work as a logic analyzer. A lot of that, we have the PIO peripherals to thank for — an assembly of state machines that even let you “bitbang” high-speed interfaces like DVI. If you’re interested in how PIO functions, there are some good write-ups around here. Lacking a Pi Pico, you can use this board’s bigger sister to interface with JTAG, too.

Screenshot of Pulseview showing capture and decode of some digital channels

Need A Logic Analyzer? Use Your Pico!

March 2, 2022 by 23 Comments

There’s a slew of hardware hacker problems that a logic analyzer is in a perfect position to solve. Whether you’re trying to understand why an SPI LCD screen doesn’t initialize, what’s up with your I2C bus, or determine the speed of an UART connection, you’ll really want to have a logic analyzer on hand. People have been using a Pi Pico as a logic analyzer in a pinch, and now [pico-coder] has shared a sigrok driver that adds proper support for a Pico to beloved tools like Pulseview.

The specs offered are impressive. Compared to the $10 “Saleae” clone analyzers we are so used to, this thing boasts 21 digital channels with up to 120 MHz capture speed, 3 ADC channels at up to 500 KHz, and hardware-based triggers. The GitHub repository linked above stores the driver files out-of-tree, but provides build instructions together with an easily flash-able uf2 firmware. It’s likely that you’ll soon see this driver in a stock Pulseview installation, however, given the submitter-friendly attitude we’ve witnessed on the sigrok mailing list. However, if you need a logic analyzer ASAP, you should follow the caringly offered quickstart guide.

We’ve covered Pulseview being used in combination with cheap accessible analyzers before — a must-watch if you need to get yourself up to speed on the value they provide to a hobbyist. If an oscilloscope is what you need and a smartphone is what you have, perhaps you’ll enjoy the Scoppy firmware for the Pico.

We thank [mip] for sharing this with us!

fiber matrix

Big LED Matrix Becomes Tiny LED Matrix Thanks To Fiber Optics

March 1, 2022 by 11 Comments

Everyone loves LED matrices, and even if you can’t find what you like commercially, it’s pretty easy to make just what you want. Need it big? No problem; just order a big PCB and some WS2812s. Need something tiny? There are ridiculously small LEDs that will test your SMD skills, as well as your vision.

But what if you want a small matrix that’s actually a big matrix in disguise? For that, you’ll want to follow [elliotmade]’s lead and incorporate fiber optics into your LED matrix. The build starts with a 16×16 matrix of WS2812B addressable LEDs, with fairly tight spacing but still 160 mm on a side. The flexible matrix was sandwiched between a metal backing plate and a plastic bezel with holes directly over each LED. Each hole accepts one end of a generous length of flexible 1.5-mm acrylic light pipe material; the other end plugs into a block of aluminum with a 35 by 7 matrix of similar holes. The small block is supported above the baseplate by standoffs, but it looks like the graceful bundle of fibers is holding up the smaller display.

A Raspberry Pi Pico running a CircutPython program does the job of controlling the LEDs, and as you can see in the video below, the effect is quite lovely. Just enough light leaks out from the fibers to make a fascinating show in the background while the small display does its thing. We’ve seen a few practical uses for such a thing, but we’re OK with this just being pretty. It does give one ideas about adding fiber optics to circuit sculptures, though.

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Turn On Sarcasm With The Flip Of A Switch

January 26, 2022 by 43 Comments

Sarcasm is notoriously difficult to distinguish in online communities. So much, in fact, that a famous internet rule called Poe’s Law is named after the phenomenon. To adapt, users have adopted several methods for indicating implied sarcasm such as the /s tag, but more recently a more obvious sarcasm indicator has appeared that involves random capitalization througout the sarcastic phrase. While this looks much more satisfying than other methods, it is a little cumbersome to type unless you have this sarcasm converter for your keyboard.

The device, built by [Ben S], is based around two Raspberry Pi Pico development boards and sits between a computer and any standard USB keyboard. The first Pi accepts the USB connection from the keyboard and reads all of the inputs before sending what it reads to the second Pi over UART. If the “SaRcAsM” button is pressed, the input text stream is converted to sarcasm by toggling the caps lock key after every keystroke.

For communicating in today’s online world with rapidly changing memes, a device like this is almost necessary for making sure you aren’t misunderstood on whichever popular forum you like to frequent. We don’t know how long this trend will continue, either, but until something else replaces it to more concisely communicate sarcasm we expect it to remain relevant. The build is also a reminder of the various interesting ways that microcontrollers can be programmed to act as keyboards.

Thanks to [ted yapo] for the tip!

New Part News: Raspberry Pi Cuts Out The Middleman

January 17, 2022 by 36 Comments

Raspberry Pi has just announced that they’ll be selling their RP2040 microcontroller chips by the reel, directly to you, at a decent discount.

About a year ago, Raspberry Pi released its first piece of custom silicon, the RP2040 microcontroller. They’ve have been selling these chips in bulk to selected customers directly, but have decided to open up the same deals to the general public. If you’re looking for 500 chips or more, you can cut out the middleman and save some serious dough.

Because the RP2040 was a clean-slate design, it uses a relatively modern production process that yields many more processors per silicon wafer, and it has been essentially spared from the chip crisis of 2020-2021. According to CEO Eben Upton, they’ve sold 1.5 million in a year, and have wafers in stock for 20 million more. You do the math, but unless you’re predicting the chip shortage to last in excess of 12 years, they’re looking good.

Game Boy Becomes Super Game Boy With A Pair Of Pis

January 14, 2022 by 13 Comments

For the Nintendo aficionados of the 90s, the Super Game Boy was a must-have cartridge for the Super Nintendo which allowed gamers to play Game Boy games on your TV. Not only did it allow four-color dot-matrix gaming on the big screen, but it let you play those favorite Game Boy titles without spending a fortune on AA batteries. While later handhelds like the PSP or even Nintendo Switch are able to output video directly to TVs without issue, the original Game Boy needed processing help from an SNES or, as [Andy West] shows us, it can also get that help from a modern microcontroller.

Testing the design before installing it in the NES case.

The extra processing power in this case comes from a Raspberry Pi Pico which is small enough to easily fit inside of a donor NES case and also powerful enough to handle the VGA directly. For video data input, the Pico is connected to the video pins on the Game Boy’s main board through a level shifter. The main board is also connected to a second Pico which handles the controller input from an NES controller. Some fancy conversion needed to be done at this point because although the controller layouts are very similar, they are handles by the respective consoles completely differently.

With all of the technical work largely out of the way, [Andy] was able to put the finishing touches on the build. These included making sure the power buttons, status LEDs, and reset button all functioned, and restoring the NES case complete with some custom “Game Guy” graphics to match the original design of the Game Boy. We commend the use of original Game Boy hardware in this build as well, which even made it possible for [Andy] and his wife to play a head-to-head game of Dr. Mario through a link cable with another Game Boy. If you’re looking for a simpler way of playing on original hardware without burning a hole in your wallet buying AA batteries, take a look at this Game Boy restoration which uses a Lithium battery instead.

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