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Introduce Yourself To a PocketBeagle With BaconBits

พฤ, 03/15/2018 - 12:00

The PocketBeagle single-board computer is now a few months old, and growing fast like its biological namesake. An affordable and available offering in the field of embedded Linux computing, many of us picked one up as an impulse buy. For some, the sheer breadth of possibilities can be paralyzing. (“What do I do first?”) Perhaps a development board can serve as a starting point for training this young puppy? Enter the BaconBits cape.

When paired with a PocketBeagle, everything necessary to start learning embedded computing is on hand. It covers the simple basics of buttons for digital input, potentiometer for analog input, LEDs for visible output. Then grow beyond the basics with an accelerometer for I²C communication and 7-segment displays accessible via SPI. Those digging into system internals will appreciate the USB-to-serial bridge that connects to PocketBeagle’s serial console. This low-level communication will be required if any experimentation manages to (accidentally or deliberately) stop PocketBeagle’s standard USB network communication channels.

BaconBits were introduced in conjunction with the E-ALE (embedded apprentice Linux engineer) training program for use in hands-on modules. The inaugural E-ALE session at SCaLE 16X this past weekend had to deal with some last-minute hiccups, but the course material is informative and we’re confident it’ll be refined into a smooth operation in the near future. While paying for the class will receive built hardware and in-person tutorials to use it, all information – from instructor slides to the BaconBits design – is available on Github. Some of us will choose to learn by reading the slides, others will want their own BaconBits for independent experimentation. And of course E-ALE is not the only way to learn more about PocketBeagle. Whichever way people choose to go, the embedded Linux ecosystem will grow, and we like the sound of that!

LED Illusion Makes Colorful Water Drops Defy Gravity

พฤ, 03/15/2018 - 09:00

The 60s and 70s were a great time for kitschy lighting accessories. Lava lamps, strobes, color organs, black light posters — we had it all. One particularly groovy device was an artificial rain display, where a small pump dripped mineral oil over vertical monofilament lines surrounding a small statue, with the whole thing lighted from above in dramatic fashion. If it sounds appalling, it was, and only got worse as the oil got gummy by accumulating dust and debris.

While this levitating water drops display looks somewhat similar, it has nothing to do with that greasy lamp of yore. [isaac879]’s “RGB time fountain” is actually a lot more sophisticated and pretty entrancing to watch. The time fountain idea is simple — drip water from a pump nozzle to a lower receptacle along a path that can be illuminated with flashing LEDs. Synchronizing the flashes to the PWM controlling pump speed can freeze the drops in place, or even make them appear to drip up. [isaac879] took the time fountain idea a step further by experimenting with RGB illumination, and he found that all sorts of neat effects are possible. The video below shows all the coolness, like alternating drops of different colors that look like falling — or rising — paint drops, and drops that merge together to form a new color. And behold, the mysterious antigravity cup that drips up and yet gets filled!

Allowances must be made for videos of projects that use strobes, of course. The effect of this time fountain and similar ones we’ve featured before is hard to capture, but this one still looks great to us.

Thanks to [xamiax] for the tip.

Interactive Plant Lamps for Quiet Spaces

พฤ, 03/15/2018 - 06:00

If you’ve spent any serious time in libraries, you’ve probably noticed that they attract people who want or need to be alone without being isolated. In this space, a kind of silent community is formed. This phenomenon was the inspiration [MoonAnchor23] needed to build a network of connected house plants for a course on physical interaction and realization. But you won’t find these plants unleashing their dry wit on twitter. They only talk to each other and to nearby humans.

No living plants were harmed during this project—the leaves likely wouldn’t let much light through, anyway. The plants are each equipped with a strip of addressable RGB LEDs and a flex sensor controlled by an Arduino Uno. Both are hot glued to the undersides of the leaves and hidden with green tape. By default, the plants are set to give ambient light. But if someone strokes the leaf with the flex sensor, it sends a secret message to the other plant that induces light patterns.

Right now, the plants communicate over Bluetooth using an OpenFrameworks server on a local PC. Eventually, the plan is use a master-slave configuration so the plants can be farther apart. Stroke that mouse button to see a brief demo video after the break. [MoonAnchor23] also built LED mushroom clusters out of silicone and cling wrap using a structural soldering method by [DIY Perks] that’s also after the break. These work similarly but use force-sensing resistors instead of flex-sensing.

Networking several plants together could get expensive pretty quickly, but DIY flex sensors would help keep the BOM costs down.

RC Car Hacked Into Paintball Shooting Tank

พฤ, 03/15/2018 - 03:00

What’s more fun, driving RC cars around on rugged terrain, or having a paintball battle? How about doing both at the same time by making an RC controlled, paintball firing tank? [Nate] from the King of Random YouTube channel did just that by mounting a modified paintball gun to a stripped-down RC car, adding an RC trigger to remotely fire the gun, and covering it all in EVA foam armor in the shape of a tank. And then he did it again so that he’d have someone to battle against.

RC car with paintball gun attached

He walks through the full build in the first video below, but here are some things that stood out for us. It took some fiddling to get a servo to pull the gun trigger but how could he remotely control the servo? For that, he took over the car’s RC receiver signal for controlling audio and made it turn on and off the servo instead. We also like his use of aluminum bar. This stuff is available in the hardware section at stores like Home Depot and is easy to cut and bend. You can see it used here for mounting Wimshurst machine parts to a bicycle, and in this hack, [Nate] used it to mount the paintball gun rigidly to the car frame. He did surprise us when he used rivets instead of nuts and bolts to hold the frame together. That’s not something you see often, and it worked great.

As we said, he made two of them. In the second video below, watch the tanks in action as [Nate] and fellow YouTuber [Stuart Edge] have a tank battle in the desert.

Incremental Sheet Forming with a CNC Machine

พฤ, 03/15/2018 - 01:30

If you want to form a piece of sheet metal into a shape, you’ll probably think about using a die. That’s certainly a great way to do it, but it presupposes you can create or purchase the die, which may be a showstopper for small projects. [Dardy-7] has worked out how to use a lesser-used technique — incremental sheet forming — to get similar results with a CNC machine. The idea is to trace out the form on the sheet metal with a round blunt tool.

He got good results using an inexpensive dapping tool, although he’s seen other use heated titanium ball bearings. In addition, he’s worked out how to adapt existing tool paths, like the ones you might download from the Internet, to use with this technique. You can see a video of the workflow below.

The technique requires a jig to hold the workpiece that allows the tool to push the metal down. In the examples, the jigs are just quick plywood assemblies and the workpiece is 0.6 mm aluminum. Some of the jigs have support underneath to help create parts that have parts poking up (that is, a positive curvature).

We couldn’t help but think that a 3D printer could easily create a backing plate that would serve the same purpose as under support in the current jigs. [Dardy-7] notes the process is slow and not as accurate as some other methods. On the other hand, if you have a CNC machine it should be an easy addition to your repertoire.

If this makes you want to run out and buy a CNC machine, you might like to read this first. If you want to dive into the tool paths, we can help you there, too.

Teardown: “The Oregon Trail” Handheld

พฤ, 03/15/2018 - 00:00

If you were a school-age child in the 1980’s or 1990’s, you almost certainly played The Oregon Trail. Thanks to its vaguely educational nature, it was a staple of school computers until the early 2000’s, creating generations of fans. Now that those fans are old enough to have disposable incomes, we are naturally seeing a resurgence of The Oregon Trail merchandise to capitalize on one of humanity’s greatest weaknesses: nostalgia.

Enter the Target-exclusive The Oregon Trail handheld game. Priced at $24.99 USD and designed to look like the classic beige-box computers that everyone of a certain age remembers from “Computer Class”, it allows you to experience all the thrills of dying from dysentery on the go. Naturally there have been versions of the game for mobile devices in the past, but how is that going to help you when you want to make your peers at the coffee shop jealous?

But we’re not here to pass judgement on those who hold a special place for The Oregon Trail in their hearts. Surely, there’s worse things you could geek-out on than interactive early American history. No, you’re reading this post because somebody has put out a handheld PC-looking game system, complete with a simplified keyboard and you want to know what’s inside it. If there was ever a cheap game system that was begging to be infused with a Raspberry Pi and some retro PC games, this thing is it.

But First…

I would be remiss if I tore the thing apart without at least playing it for a bit and commenting on the system as a whole. I have to say, it’s pretty impressive given how cheap it is. The case feels strong, the buttons respond nicely, and I can’t help but love the satisfying “ker-chunk” the power button (the gray bar in the “floppy drive”) makes. That noise brings me right back to the days of DOS gaming on my 386.

The screen is surprisingly sharp, though a bit dim compared to the smartphones we spend our days staring into. Even though it’s very small by modern standards, everything is perfectly readable and the graphics, such as they are, look great.

Alright, now that we’ve put away our rose-tinted glasses, let’s see what’s hiding inside of this faux-PC.

Room to Grow

So the first thing you notice inside The Oregon Trail is that it’s absolutely cavernous inside. The case must be at least twice as big as it needs to be, the majority of the device is just dead space. You could easily fit the Pi 3 inside of the case, to say nothing of the Pi Zero. There’s also plenty of space to put a rechargeable battery, which is good because the three AAs that power the device aren’t likely to get you very far.

To put some numbers to it, the inside of the case is about 140 mm long, 82 mm wide, and 40 mm deep. I really can’t stress how much open area there is inside the case, you could literally fill the thing with rocks and then easily screw it back together. It seems exceptionally wasteful from a materials standpoint, but absolutely fantastic if you’re trying to put extra gear inside.

Main Board and LCD

As you might expect, the main board of The Oregon Trail is hiding most of its goodies under black epoxy blobs. There’s a dizzying array of test points, but none labeled to say what they do. There are a few solder jumper pads which looked interesting, but after bridging them in different combinations I didn’t notice anything changing the game. I thought for sure they would at least change the language, but no dice.

One of the devices on the board has had the label completely obliterated, but the other two were visible under the microscope.

The HT24LC08 is a 1KB serial EEPROM, so if you want to hack the contents of your wagon, this would likely be the place to do it. I’m not sure about the other chip, G25Q80CW. The searches I’ve done have come up empty handed.

Of course, the main board is likely to get chucked in the bin by anyone who buys The Oregon Trail to modify it, so we won’t dwell too long on the specifics.

As for the screen, the flex cable is directly soldered to the back to the main board. The ID ZSX0243 is printed on the back of the panel and is even embossed on the ribbon cable, but as with the second chip on the main board, I haven’t found any useful info online about how one might interface with it.


In what’s likely the most exiting bit of news, the keyboard on The Oregon Trail is exceptionally hackable. It’s a simple membrane keypad, and each wire is individually labeled for your convenience (on the keyboard and main board side). It’s ready to get soldered directly into the GPIO pins of your favorite microcontroller or SBC.

The biggest problem I see is the rather limited utility of the keys currently on the game. The directional pad (with diagonals) is nice, but not sure what kind of mileage you’ll really get out of a “Wagon” button. The best bet might be to repaint the keys, or go all out and 3D print new ones with whatever iconography works for your intended purposes.

Incidentally, remember that nostalgic sound I said the power button makes when you push it? Come to find out, the reason it sounds like a computer power switch is because that’s exactly what they used, complete with spring-assist. I’d recognize that little switch anywhere. I don’t know if that was an intentional little detail on the part of the designers, or just the easiest way for them to implement a hard power switch, but I’ll take it either way.

All told, the physical controls on The Oregon Trail should be very easy to implement into whatever project you might have in mind, and with a little cosmetic retouching of the keys, should make for a pretty slick setup.

Final Thoughts

Playing The Oregon Trail for a bit was fun, and I think they did a respectable job of bringing the experience of the game back to life on this new platform. But the fact is, you can just play the game on your computer or phone every couple years when the crushing depression of real life forces you to relive your youth for an hour or so. By then you’ll remember we have YouTube now, and move on.

I think it offers much better value as a platform for hacking. For $25 USD you’ve got a very cool looking case that’s got plenty of room inside, and a turn-key user interface that almost looks like it was designed to be re-purposed. Its even got a power button and speaker mounted and wired up. Honestly, the thing is nearly a retro emulator kit.

Whether it’s bought by Millennials who are feeling nostalgic for their school days or hackers looking to tear it apart and make a handheld DOOM, I think Target is going to be laughing their way to the bank with this one.

Stephen Hawking’s Legacy Includes Making His Work Widely Approachable

พุธ, 03/14/2018 - 23:01

We are saddened by the passing of physicist Stephen Hawking. One of the great minds of our time, Hawking’s work to apply quantum theory to black holes launched his career and led to his best known theoretical discovery that black holes emit radiation, aptly known as Hawking radiation.

Thinking back on Stephen Hawking’s contributions to humanity, it strikes us that one of his most important is his embrace of pop culture. While his scientific discoveries and writings are what will stand the test of time, in our own age it is remarkable that Stephen Hawking is a household name around the world.

Hawking’s first book, A Brief History of Time, has sold more than 10 million copies and for many readers was their introduction into the way physicists view space and time. It was written for general consumption and not reserved for those who were already bathed in the jargon of theoretical physics. It sent the message that contemplating science is something that is fun to do in your spare time. This work continued with his more recent mini-series Into the Universe with Stephen Hawking created for the Discovery Channel.

A fan of the series, Hawking appeared in an episode of Star Trek: The Next Generation in 1993 and made subsequent, often repeat, appearances on The SimpsonsFuturama, and The Big Bang Theory. This was great fun for all science geeks who knew of his work, but it has a far more profound effect of normalizing interaction with a world-class scientist. Appearing on these shows told the story that the pursuit of knowledge is cool.

Having scientists in the public light is crucial to research and advancement. It lets the general public know what kind of frontiers are being pursued, and why that matters. This trickles both up and down, inspiring the next generation of scientists by introducing deep topics at an early age, and ensuring funding and opportunities for this upcoming wave of researchers has widespread support.

Stephen Hawking showed us some incredibly complicated secrets of the cosmos both through his discovery, and through his ambassadorship of scientific knowledge. He will be greatly missed but leaves behind an admirable legacy which we can all strive to live up to.

[Main image by Martin Pope via The Telegraph]

Friday Hack Chat: Everything Raspberry Pi

พุธ, 03/14/2018 - 22:00

The Raspberry Pi is six years old now, and in that time it’s become the most popular single board computer. Over these last few years, the Pi has improved from a relatively anemic board based on a smartphone SoC to a surprisingly fast board that’s loaded up with some of the best software and the best community support we’ve ever seen. There’s an awful lot you can do with a Pi, and the continued support of the Raspberry Pi Foundation has enabled millions of people to get their hands on a cheap computer that runs Linux. It’s great.

Now it’s your turn to ask the engineers behind this tiny little computer what’s going on in the world of Pi. We’re having a Hack Chat this Friday, and you’re invited.

Our guest for this week’s Hack Chat will be [Roger Thornton], principal hardware engineer for the Raspberry Pi, where he oversees design, test, compliance, and production for Raspberry Pi products. Previously, [Roger]’s work for Broadcom included being part of the team that characterized and tested numerous SoCs including the BCM2835/6/7 found in various Pis. He also has experience in the smart home and IoT fields from working in a consultancy where be helped bring chips to market.

[Roger]’s most recent work was announced today; the Raspberry Pi 3 Model B+ is the latest in a long line of Pis, and while it’s not the octocore ARM monster with SATA and PCIe and Gigabit networking and 4G that the power-hungry have been clamoring for, it is more capable than its predecessor and still only costs less than forty bucks.

This is also the second time [Roger] has been a guest on our Hack Chats. You can check out the transcript of the 2017 chat here.

During this chat, we’re going to be discussing the future of Raspberry Pi products, Pi events around the world, and a question on the minds of many: where you can buy Pi Zeros in quantity. You are, of course, encouraged to add your own questions to the Hack Chat. You can do that by leaving the questions as a comment on this Hack Chat’s event page.

Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week it’s going down at the usual time, on noon, Pacific, Friday, March 16th  Want to know what time this is happening in your neck of the woods? Have a countdown timer!

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.

You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.

Archimedes Would Have Known Better If He Could Count To A Million

พุธ, 03/14/2018 - 21:01

Today is March 14th, or Pi Day because 3.14 is March 14th rendered in month.day date format. A very slightly better way to celebrate the ratio of a circle’s circumference to its diameter is July 22nd, or 22/7 written in day/month order, a fractional approximation of pi that’s been used for thousands of years and is a better fit than 3.14. Celebrating Pi Day on July 22nd also has the advantage of eschewing middle-endian date formatting.

But Pi Day is completely wrong. We should be celebrating Tau Day, to celebrate the ratio of the circumference to the radius instead of the diameter. That’s June 28th, or 6.283185…. Nonetheless, today is Pi Day and in the absence of something truly new and insightful — we’re still waiting for someone to implement a spigot algorithm in 6502 assembly, by the way — this is a fantastic opportunity to discuss something tangentially related to pi, the history of mathematics, and the idea that human knowledge builds upon itself in an immense genealogy stretching back to the beginning of history.

This is our Pi Day article, but instead of complaining about date formats, or Tau, we’re going to do something different. This is how you approximate pi with the Monte Carlo method, and how anyone who can count to a million can get a better approximation of one the fundamental constants of the Universe than Archimedes.

What Is Monte Carlo?

Before we dig into this, it’s important to describe what the Monte Carlo method of problem solving actually is. In short, it’s measuring or simulating some sort of system with the application of random numbers. Any sufficiently complete history of Monte Carlo method of problem solving begins with Buffon’s needle problem, but this example muddles the issue, and came about two hundred years before this sort of randomness was applied to statistical insight.

The true origin of Monte Carlo simulations came from the development of the hydrogen bomb in the late 1940s. Stanislaw Ulam is credited with discovering this technique when investigating exactly how much neutron shielding would be needed in a certain application. The problem couldn’t be solved, but there was a probability distribution for this system. The key factors of the design were known — how far a neutron would travel through a medium, and how much energy would be given off when colliding with the nucleus of an atom. The solution to this problem was to simply throw random numbers at the problem, letting the known probability distribution take care of the rest.

Working through an example of the Monte Carlo method is a much better way of understanding, so let’s do that. This is how you approximate a value for pi using hundreds of thousands of random numbers.

So How Do We Estimate Pi?

What we’re doing here is drawing a circle, with a diameter of two (a radius of one). This is commonly known as a unit circle. This circle is inscribed into a square with a side length of two. We place hundreds of thousands of random points inside the square, count the total number of points placed and comparing that with the total number of points inside the circle. Because we’ve chosen a radius of one, and the area inside the circle is , we can use Total Points / Inside Points to give us an approximation of Pi.

If there’s one thing computers are good at, it’s counting. So with a little bit of Python, we can easily run our experiment:

import random as dot import math as m # Total number of random points. total = 1000000 # Points contained in the circle. inside = 0 #Main loop for i in range(0, total): # Place random dots in unit square x2 = dot.random()**2 y2 = dot.random()**2 # Check if inside circle, # increment counter if inside if m.sqrt(x2 + y2) < 1.0: inside += 1 # We're only doing positive x/y coords, # so multiply by four. pi = (float(inside) / total) * 4 # Print result print(pi) # Print difference difference = m.fabs(pi - m.pi) print(difference)

An explanation of what’s going on in this code should be in order. We set our total points at 1,000,000 and iterate through that range. Each iteration sets a random X and random Y coordinate and places the point on our plane. Determining the total number of points inside the circle is calculated with  x² + y² < 1.0. If that equation is satisfied the “inside” points value is incremented.

That’s the jist of the above code, with one caveat; we don’t need to deal with negative x and y coordinates. We can simply ignore those, and multiply the ratio of the number of random points inside the circle over the total number of points by four.

After a few dozen runs of this small script, I rarely got a result that was off by more than 0.002. Most results ranged from 3.141 to 3.143. That may not sound impressive to anyone that can rattle off the first dozen or so digits of pi from memory, but consider the historical alternative. Archimedes’ best estimate for pi was 223 / 71 < π < 22 / 7, or two decimal places. Ptolemy calculated pi to three decimal places, and in the third century, Chinese mathematicians managed to figure out five decimal places. The Monte Carlo method, which is simply counting a dividing albeit on a scale no human should ever have to do, improves on any of these numbers. Do this, and you know pi to more places than Fibonacci.

A Truly Modern Technique

One thing that’s so easy to forget is that ancient people were just as smart as anyone walking down the street today. It’s not fair to discount ancient beliefs that whales are fish, that the Earth is flat, the value of mathematical constants, or even what our solar system looks like simply because someone lived a few thousand years before us. They simply didn’t know any better. Is it fair to criticize Archimedes for not calculating a better value of pi? No, and not just because it would involve counting to a million.

The Monte Carlo technique is an inherently modern technique. It involves randomness, and it’s not a mistake this technique was discovered when attempting to find a solution to a problem involving probability and quantum mechanics. The ancients simply didn’t have the tools to discover this technique.

It’s like the solution to Fermat’s last theorem, or a numeric solution for n > 2 in the equation an + bn = c. A solution was finally found by [Andrew Wiles] in the 1990s, but it was completely unlike any sort of math Fermat would have known of, or anyone else on the planet for that matter. We don’t know if Fermat actually solved this problem, or what his proof would be, but it would have been so simple anyone could understand it instead of [Wiles]’s deep dive into obscure maths.

Could Archimedes have calculated Pi to a greater precision than anyone else by throwing marbles at a circle and square traced out in the sand? No. The knowledge we have today, and what children are taught in grade school, is built upon thousands of years of the brightest minds working on the hardest problems. Flashes of genius are so rare on a species-wide scale that scientific and mathematical advancement happens at a snail’s pace. We should hope that we’re not judged too unkindly a few thousand years down the line — we simply didn’t know any better.

RC Transmitter Hacked Into Music Player

พุธ, 03/14/2018 - 18:00

Packed with an incredible amount of hardware, and increasingly likely to be running an open source firmware, the modern RC transmitter is effectively a little multi-purpose computer in its own right. Accordingly there is a small, but growing, community of developers coming out with software applications targeting these switch-festooned wonders. It’s only a matter of time until they are running DOOM.

One such piece of software is TaraniTunes, developed by [GilDev]. This program allows you to load your OpenTX 2.2+ equipped Taranis Q X7 or Taranis X9D with music files which can be played on the transmitter’s built-in speaker. While it likely won’t win any awards for interface design, the large LCD display coupled with the radio’s numerous physical buttons and switches makes it relatively easy to navigate your music collection.

While the software [GilDev] has written for OpenTX looks straightforward enough, getting the songs on the radio is another story. For each track you need to merge the stereo channels into mono (as the transmitter only has a single speaker), and then convert it to a 32 kHz WAV. But don’t worry about the lack of ID3 tag information, TaraniTunes allows you to create a text file containing not only the filename of each track, but its name and artist.

We’ll admit this one should be filed away in the “Because I Can” category, but it’s still an impressive hack and a clever demonstration of the current state of RC transmitter technology.

Raspberry Pi Gets Faster CPU and Better Networking in the New Model 3 B+

พุธ, 03/14/2018 - 14:01

While the Raspberry Pi’s birthday (and the traditional release date for the newest and best Pi) was a few weeks ago, Pi Day is a fitting enough date for the introduction of the best Pi to date. The Raspberry Pi 3 Model B+ is the latest from the Raspberry Pi foundation. It’s faster, it has better networking, and most interestingly, the Pi 3 Model B+ comes with modular compliance certification, allowing anyone to put the Pi into a product with vastly reduced compliance testing.

A Small Speed Boost For The CPU, A Huge Leap For The LAN

When the Raspberry Pi was first announced, it was heralded as a legitimate desktop computer, capable of everything from word processing to web browsing, all for less than $40. The first batch of Pis sold like hotcakes, but using this computer as a desktop replacement was a slightly frustrating experience. With the release of the Raspberry Pi 3 in 2016, this changed. The Pi was fast enough and the software was good enough that, yes, this was a capable computer suitable for light web work and even a few computationally expensive tasks. Add onboard wireless, and the Pi 3 Model B was a great computer.

The newest member of the Raspberry Pi family remains a great computer, but don’t expect a truly massive speedup from this upgrade. The processor is still the Broadcom BCM2837 found in the Raspberry Pi 3, a quad-core A53, 64-bit CPU. There is a slight upgrade over the Raspberry Pi 3; thanks to improved power integrity, thermal design, and possibly a metal can over the CPU, the Raspberry Pi 3 Model B+ now runs at 1.4 GHz, instead of the 1.2 GHz of its predecessor.

The most visually striking difference between the old Pi 3 and the Pi 3 Model B+ is the embossed metal shield over the RF guts of the board. This houses the new, dual-band 2.4 and 5GHz wireless LAN, and Bluetooth 4.2/BLE. The Pi 3 used a BCM43438, which only supported 2.4GHz WiFi, whereas the new wireless chipset is significantly more capable and able to work with 5GHz networks.

But that metal shield covering the new wireless chipset isn’t just for decoration. The Raspberry Pi 3 Model B+ comes with modular compliance certification. This allows the Pi 3 Model B to be used in products with significantly reduced compliance testing.

Much Better Wired Networking The new LAN7515 USB and Ethernet controller

While these are welcome changes, this isn’t the biggest reveal for the Pi 3 Model B+. Before the introduction of wireless on the Pi 3, the Ethernet was severely constrained by the LAN9514 USB hub and Ethernet controller. This chip provided the four USB ports and Ethernet to the Pi’s SoC, but networking was limited to 100 Mbps in the best case, and somewhere around 80 Mbps in real-world usage.

The Pi 3 Model B+ changes this by replacing the USB and Ethernet controller with a LAN7515. It’s still a capable USB 2.0 hub and Ethernet controller, but this one gives the Pi 3 Model B+ 300 Mbps Ethernet. It’s a great feature if you’re using a Pi as a home server, or just want to send a lot of data to a Pi over a wired network.

So What’s In The Can?

Being the first Raspberry Pi featuring an RF shield, there is the obvious question of what’s under the can?. The bad news is, removing that RF shield will void any warranty, allow the Pi to spew RF everywhere, and there will be no hope of meeting compliance. The good news is that there are some really cool components under there.

The chip responsible for all the wireless functionality is a CYW43455, a Cypress and/or Broadcom part capable of 802.11ac with support for 2.4 and 5GHz WiFi, and Bluetooth 4.2. The Raspberry Pi 3 Model B — last year’s model — featured a BCM43438, that did not include support for 5GHz radios or Bluetooth 4.2.

It’s a welcome addition, but the real story here is the RF shield that helped secure this board’s modular compliance certification. Now you can use this board in a product and won’t have to pay for the expensive intentional radiator testing required of all new products featuring their own home-spun radios.

Power over Ethernet (PoE) Header Designing a new Pi hat? Make sure to take these headers into account.

Although I wouldn’t necessarily call it a failing of the latest Pi, there is something you might want to watch out for. The addition of Power over Ethernet (with an add-on hat), may get in the way of other Pi hats.

The PoE header is placed next to the USB ports, right under one of the Pi’s mounting holes and next to the 40-pin header. These pins are the same height as the 40-pin header, and I can easily envision a situation where already existing Pi hats will interfere with the PoE header.

This is also right where the ‘Run’ header was placed in the Pi 3 Model B, and I’m sure there are a few products out there that make mechanical use of this header designed for reset buttons. Is it terribly broken? No, but it will ruin somebody’s day eventually.

While it’s not a Raspberry Pi with SATA or PCIe or whatever people with unrealistic expectations are clamoring for, the Raspberry Pi 3 Model B+ is a capable and desirable upgrade for what is now the most popular computer on the planet for varying definitions of ‘computer’.

Pocket-Sized Multiduino Does it All

พุธ, 03/14/2018 - 12:00

How many times have you wished for a pocket-sized multimeter? How about a mini microcontroller-based testing rig? Have you ever dared to dream of a device that does both?

Multiduino turns an Arduino Nano into a Swiss Army knife of portable hacking. It can function as an analog multimeter to measure resistance, voltage drop, and continuity. It can also produce PWM signals, read from sensors, do basic calculator functions, and display the health of its rechargeable battery pack.

Stick a 10kΩ pot in the left-side header and you can play a space shooter game, or make line drawings by twisting the knob like an Etch-A-Sketch. Be sure to check out the detailed walk-through after the break, and a bonus video that shows off Multiduino’s newest functions including temperature sensing, a monophonic music player for sweet chiptunes, and a virtual keyboard for scrolling text on the OLED screen. [Danko] has a few of these for sale in his eBay store. They come assembled, and he ships worldwide. The code for every existing function is available on his site.

More of a maximalist? Then check out this Micro-ATX Arduino.

Thanks for the tip, [Rahul].

Up AlphaGoer Five

พุธ, 03/14/2018 - 09:00

AlphaGo is the deep learning program that can beat humans at the game Go. You can read Google’s highly technical paper on it, but you’ll have to wade through some very academic language. [Aman Agarwal] has done us a favor. He took the original paper and dissected the important parts of in in plain English. If the title doesn’t make sense to you, you need to read more XKCD.

[Aman] says his treatment will be useful for anyone who doesn’t want to become an expert on neural networks but still wants to understand this important breakthrough. He also thinks people who don’t have English as a first language may find his analysis useful. By the way, the actual Go matches where AlphaGo beat [Sedol] were streamed and you can watch all the replays on YouTube (the first match appears below).

Interestingly, the explanation doesn’t assume you know how to play Go, but it does presuppose you have an understanding of some kind of two-player board game. As an example of the kind of language you’ll find in the original paper (which is linked in the post), you might see:

The policy network is trained on randomly sampled state-action pairs (s,a) using stochastic gradient ascent to maximize the likelyhood of the human move a selected in state s.

This is followed by some math equations. The post explains stochastic gradient ascent and even contrasts it to another technique for backpropagation, stochastic gradient descent.

We have to say, we’d like to see more academic papers taken apart like this for people who are interested but not experts in that field. We covered the AlphaGo match at the time. Personally, we are always suckers for a good chess computer.

Building A Lightweight Softbox For Better Photography

พุธ, 03/14/2018 - 06:00

If you want to take good photographs, you need good light. Luckily for us, you can get reels and reels of LEDs from China for pennies, power supplies are ubiquitous, and anyone can solder up a few LED strips. The missing piece of the puzzle is a good enclosure for all these LEDs, and a light diffuser.

[Eric Strebel] recently needed a softbox for some product shots, and came up with this very cheap, very good lighting solution. It’s made from aluminum so it should handle the rigors of photography, and it’s absolutely loaded with LEDs to get all that light on the subject.

The metal enclosure for this softbox is constructed from sheet aluminum that’s about 22 gauge, and folded on a brake press. This is just about the simplest project you can make with a brake and a sheet of metal, with the tabs of the enclosure held together with epoxy. The mounting for this box is simply magnets super glued to the back meant to attach to a track lighting fixture. The 5000 K LED strips are held onto the box with 3M Super 77 spray adhesive, and with that the only thing left to do is wire up all the LED strips in series.

But without some sort of diffuser, this is really only a metal box with some LEDs thrown into the mix. To get an even cast of light on his subject, [Eric] is using drawing vellum attached to the metal frame with white glue. The results are fairly striking, and this is an exceptionally light and sturdy softbox for photography.

Automatic DIY Wire Stripper

พุธ, 03/14/2018 - 03:00

Breadboards are a great way to get started with electronics, they can remove the need for soldering which saves time for beginners who are still getting to grips with the basics of electricity, and they allow quick and easy changes to be made without the risk of melting components. However, they do require the stripping of a lot of hook up wires. While these are readily available off-the-shelf, [Stuart] decided a better solution was in order.

The project starts with a set of standard hand-operated wire strippers. A lasercut acrylic frame is then built, with a series of motors and gears to handle the transport of the wire to be stripped and to open and close the jaws of the wire strippers. Wire is fed in, stripped, fed further, stripped again, and then finally cut. The process then begins anew.

The machine is quite pleasant to watch in action, with a series of motors and limit switches helping to control the mechanism. It’s a great way to populate kits that require plenty of hookup wire without having to resort to the more common pressed-on jumper terminals that dominate the post-Arduino era. For context’s sake, this build is from the distant past, circa 2009. Plans to recreate it are available on Thingiverse. Video after the break.

Given this is the future, perhaps you’d prefer your wires laser-stripped instead?

[Thanks to Nikolai for the tip!]

A DIY 5V-3V Switching Converter in the Space of a TO-220 Package

พุธ, 03/14/2018 - 01:30

We’re suckers for miniaturization projects. Stuff anything into a small enough package and you’ve probably got our attention. Make that something both tiny and useful, like this 5-volt to 3.3-volt converter in a TO-220 sized package, and that’s something to get excited about. It’s a switch mode power supply that takes the same space as a traditional linear regulator.

Granted, the heavy lifting in [Kevin Hubbard]’s diminutive buck converter is done by a PAM2305 DC-DC step-down converter chip which needs only a few supporting components. But the engineering [Kevin] put into this to squeeze everything onto a scrap of PCB 9-mm on a side is impressive. The largest passive on the board is the inductor in 0805. Everything else is in 0603, so you’ll be putting your SMD soldering skills to the test if you decide to make this. Check the video after the break for a speedrun through the hand soldering process.

The total BOM including the open-source PCB only runs a buck or two, and the end result is a supply with steady 750-mA output that can handle a 1-A surge for five seconds. We wonder if a small heatsink tab might not help that; along with some black epoxy potting, it would at least complete the TO-220 look.

[Kevin]’s Black Mesa Labs has a history of turning out interesting projects, from a legit video card for Arduino to a 100-watt hotplate for reflow work that’s the size of a silver dollar. We’re looking forward to whatever’s next — assuming we can see it.

Need a small DC/DC 3W switcher to drop 5V to 3V in a 7805 TO-220 pinout? Or maybe just want to learn to surface mount solder 0603 components. Check out this $3 OSH project from Black Mesa Labs. $0.60 PCBs from @oshpark, $2 BOM from @digikey. https://t.co/YmB9mbYFbW pic.twitter.com/HaTes33O9f

— Kevin Hubbard (@bml_khubbard) March 4, 2018

[via Dangerous Prototypes]


Stephanie Kwolek: Saving Lives with Kevlar

พุธ, 03/14/2018 - 00:01
Almost a really bad day in the woods.

Like most accidents, it happened in an instant that seemed to last an eternity. I had been felling trees for firewood all afternoon, and in the waning light of a cold November day, I was getting ready to call it quits. There was one tiny little white pine sapling left that I wanted to clear, no thicker than my arm. I walked over with my Stihl MS-290, with a brand new, razor sharp chain. I didn’t take this sapling seriously — my first mistake — and cut right through it rather than notching it. The tree fell safely, and I stood up with both hands on the saw. Somehow I lost my footing, swiveled, and struck my left knee hard with the still-running chainsaw. It kicked my knee back so hard that it knocked me to the ground.

In another world, that would likely have a been a fatal injury — I was alone, far from the house, and I would have had mere minutes to improvise a tourniquet before bleeding out. But as fate would have it, I was protected by my chainsaw chaps, full of long strands of the synthetic fiber Kevlar.

The chain ripped open the chaps, pulled the ultrastrong fibers out, and instantly jammed the saw. I walked away feeling very stupid, very lucky, and with not a scratch on me. Although I didn’t realize it at the time,  I owed my life to Stephanie Kwolek.

Fashionably Scientific

Stephanie Kwolek’s life story is a study in contrasts. Born in 1923 in a rural town outside of Pittsburgh, Stephanie enjoyed a happy childhood with strong yet gentle influences from loving parents, both Polish immigrants. Her mother had a love of fashion, and Stephanie enjoyed watching her sew dresses. She imitated her mother at first with paper dolls, and later took up sewing herself, making many of her own clothes. Her interest in fashion stayed with her, to the point that she would seriously consider a career as a designer.

Stephanie Kwolek, 8th Grade Graduation. Source: University of Houston

Her father was an amateur naturalist who would take her on long walks in the Pennsylvania woods, observing the flora and the fauna and teaching Stephanie how to catalog and classify the natural world. Sadly, her father died when she was only 10, but the interest in the natural world he inspired in her never left. She excelled in school, especially her math and science classes, doing “much more reading than was intended for someone of my years,” as she put it.

After graduating high school, she enrolled in the Carnegie Institute of Technology, now known as Carnegie-Mellon University, in Pittsburgh. It was 1942, and even though the world was tearing itself to pieces, her timing would prove to be propitious. Stephanie enrolled in the chemistry program, and unlike so many women in science at that time, she experienced little of the usual “old boy’s club” exclusion. Perhaps thanks to the fact that so many men of her generation were absent from the classrooms (but more likely due to how bright she was) Stephanie was not only allowed and encouraged to study chemistry alongside the men, she was actively included in their groups. In her first year at Carnegie, she was even appointed to a panel by the chemistry faculty and encouraged to present her work.

Temporary Employment

As her undergraduate years were wrapping up, Stephanie was still on the fence about what to do with herself. A career in fashion design still intrigued her, and she also toyed with the idea of becoming a teacher. But she thought the best use of her new chemistry degree would be a career in medicine. Then as now, medical school is an expensive endeavor, so to save up for that, Stephanie took a temporary job in 1946 at the DuPont Company. She worked in the Polymer Chemistry division in Buffalo, New York.

The Nylon Rope Trick. By Thctamm (Own work) [CC BY-SA 3.0], via Wikimedia CommonsThe coming post-war boom years would prove to be a great time to be a chemist, and as the years flew by, Stephanie realized that her temporary job had become a full-time passion. She relocated to the company’s R&D headquarters in Delaware and threw herself into the world of polymers. She was lucky enough to land in the group that had only recently invented Nylon. Left to her own devices, she flourished, coming up with such innovations as the classic Nylon Rope Trick demonstration where a strand of nylon is reeled out of a beaker of liquid. This phenomenon is a staple of STEM experiments to this day.

Stephanie’s 20s quickly became her 40s, and in 1965 her group was tasked with finding a new, lightweight substitute for steel belting in automobile tires, on fears of a looming oil shortage and in anticipation of a market for lighter tires. While working on reactions with terephthalates and benzamides, Stephanie kept coming up with a strange side product — a runny, opalescent solution with the color of buttermilk. Interesting polymers are almost universally viscous, and her colleagues advised her to toss the stuff.

Stephanie found the substance intriguing and didn’t toss it away, instead asking the lab’s technician to run it through the spinneret, a device for turning polymer solutions into fibers. He declined, not wanting to clog his instrument with what he thought was a solution filled with flocculant particles. Stephanie persisted, showing him that the solution would pass through a filter without leaving any residue; she would later learn that this was because she had created the world’s first liquid crystal polymer, which accounted for the solution’s opalescence. The technician relented, and the world’s first aromatic polyamide fibers were spun.

Stephanie quickly characterized the fibers, finding them immensely strong and stiff. The tensile strength-to-weight ratio was five times greater than steel, and coupled with its thermal properties, including excellent performance under cryogenic conditions, the new fiber was clearly going to be big. DuPont management was quick to commercialize the product, dubbing it Kevlar.

A Legacy of Saved Lives

Stephanie’s invention hit the market in the early 1970s, and while Kevlar, its derivatives, and associated aramid fibers like the fireproof fabric Nomex have been incorporated into thousands of industrial, military, and consumer products, her involvement with the fiber largely ended once she filed her patent.

She continued her work on polymers for another two decades. In 1995 she would win the Lavoisier Medal for Technical Achievement, still the only woman to have done so. She was inducted into the National Inventors Hall of Fame that year too, and into the National Women’s Hall of Fame in 2003. She always contended, though, that the true reward of her labors was the lives saved by her invention.

Stephanie worked for DuPont for 40 years, retiring in 1986. She remained active in science and education for many years after that, and she died in 2014, about eight months before her invention kept me from chopping off my leg. Had I only known, it would have been nice to give her a call and let her know how much I appreciate her work.

Hacked 3D TV Glasses May Cure Lazy Eye

อังคาร, 03/13/2018 - 22:31

Lazy eye (technically Amblyopia) is a sight disorder that affects about 3% of the population where one eye is stronger than the other. Historically, treatment is via an eyepatch or special drops, but research shows that it may be better not to cover up the strong eye for long periods. It suggests that occluding the eye for short periods using a liquid crystal panel can yield better results. To that end, [Raninn] decided to hack some LCD glasses meant for 3D TV viewing to make a low-cost lazy eye treatment device.

This is his second version of [Raninn’s] glasses. The first one took two batteries and didn’t generate enough voltage for the LCD panels. The newer design uses a Dickson charge pump to generate a higher voltage from the battery and surface mount MOSFETs to switch voltages to the panels.

The write up is very complete with details about how to create even the PC board. He didn’t get into a lot of details about hacking the glasses. We assume that’s because your glasses may be different from his. These shutter glasses aren’t too complicated, you’ll just need to find the connections to the panel.

One of our favorite shutter glasses hacks came from [Dino] who built a set of automatic sunglasses for himself. Many of us wear glasses and for those with bifocals we keep waiting for an eyeglasses hack that makes automatic mult-focals a reality.

Review: LimeSDR Mini Software Defined Radio Transceiver

อังคาร, 03/13/2018 - 21:01

It’s fair to say that software-defined radio represents the most significant advance in affordable radio equipment that we have seen over the last decade or so. Moving signal processing from purpose-built analogue hardware into the realm of software has opened up so many exciting possibilities in terms of what can be done both with more traditional modes of radio communication and with newer ones made possible only by the new technology.

It’s also fair to say that radio enthusiasts seeking a high-performance SDR would also have to be prepared with a hefty bank balance, as some of the components required to deliver software defined radios have been rather expensive. Thus the budget end of the market has been the preserve of radios using the limited baseband bandwidth of an existing analogue interface such as a computer sound card, or of happy accidents in driver hacking such as the discovery that the cheap and now-ubiquitous RTL2832 chipset digital TV receivers could function as an SDR receiver. Transmitting has been, and still is, more expensive.

The LimeSDR Mini’s chunky USB stick form factor.

A new generation of budget SDRs, as typified by today’s subject the LimeSDR Mini, have brought down the price of transmitting. This is the latest addition to the LimeSDR range of products, an SDR transceiver and FPGA development board in a USB stick format that uses the same Lime Microsystems LMS7002M at its heart as the existing LimeSDR USB, but with a lower specification. Chief among the changes are that there is only one receive and one transmit channel to the USB’s two each, the bandwidth of 30.72 MHz is halved, and the lower-end frequency range jumps from 100 kHz to 10 MHz. The most interesting lower figure associated with the Mini though is its price, with the early birds snapping it up for $99 — half that of its predecessor. (It’s now available on Kickstarter for $139.)

We were lucky enough to be sent a pre-production LimeSDR Mini for review by the MyriadRF folks — in fact we were sent two of them, after the first one proved to have a hardware fault suspected to involve a solder joint issue. We feel their pain, after all who hasn’t had pre-production boards springing faults at inconvenient moments!

The laser cut case that will be available for your Mini.

The board itself is a PCB about 33 mm x 70 mm (1,25 ” x 2.75 “), with a USB 3 plug at one end and a pair of SMA sockets at the other, one for receive and the other for transmit. The integrated circuits are all on the top of the board, and though they have included footprints screening cans, they are not populated. There is a single multicolor status LED between the SMA sockets. It’s worth mentioning that there will be a laser-cut plastic case for the board, which is probably worth getting as it feels somewhat vulnerable as it is. Along with as the board, they supplied a pair of little rubber duck antennas for the 870 MHz band.

A couple of little 870MHz antennas are supplied with the board.

It is evident that the LimeSDR Mini is an extremely capable board that in the hands of a real expert in SDR and FPGA programming could have the potential for great things. It is also evident that as your Hackaday scribe I am not an SDR extreme power user. Despite holding an amateur radio licence for over three decades I have been a relative late comer to the world of SDRs, and have not progressed beyond RTL-SDRs or simple devices using a PC soundcard for baseband. But it’s probable that while many SDR programming experts will indeed buy this board, the majority of its customers will be similarly newcomers to the art. Therefore this review will be biased towards the SDR non-guru, the long-time radio enthusiast considering the LimeSDR Mini as a first transceiver.

The first task with any SDR will always be to install whatever software is required on the host machine. Here that means a copy of the latest Ubuntu distribution, but Windows and MacOS machines are also supported. There is a handy page of instructions, which in the case of Ubuntu require you to add a PPA repository for the drivers, then install the Lime Suite software and the SoapySDR abstraction layer. It is this final package that makes the LimeSDR an interesting prospect, by offloading software compatibility onto the widely used abstraction layer they hope to avoid some of the pain seen with other products.

Testing it Out A British DAB digital radio multiplex, as seen through a LimeSDR.

Once the drivers have been installed, it is time to decide which software to run first. The Lime Suite GUI supplied with the driver packages will be the first port of call to test the board, but I am told that the version in the PPA at the time of writing with the Mini not having been released is written with the LimeSDR USB in mind and therefore I should use GQRX. In the case of Ubuntu this can be installed through the graphical software installer, but as luck would have it I already had it on my machine. Selecting “other” as my SDR and pasting driver=lime,soapy=0 as my device string soon had the familiar interface in front of me, and with a suitable antenna in no time I was listening to my local BBC Radio 4 FM transmitter.

A simple FM transmitter, derived from this example by [Gyaresu].Two things are immediately apparent to an owner of an RTL-SDR, gone are the huge number of spurious peaks, and the noise floor is much lower. Reading GQRX with different front ends is an inexact and even slightly meaningless way to take measurements, but with all-automatic AGC, the RTL has a -60 dB noise floor and the LimeSDR has one below -90 dB. Just looking at the FM band, there are stations poking out of the noise that simply don’t exist with the RTL. It’s unsurprising that a piece of dedicated SDR hardware would outperform a $10 TV stick running a hack to make it an SDR, but if you are an RTL-SDR user then you will be pleasantly surprised by the Mini when you see it in action.

Fortunately there is nothing too sensitive controlled by this 433MHz waveform that I have just revealed to the world.

To have a board like the Mini and simply use it for GQRX is to waste so much of its potential. We are promised a library of tailor-made applications via Snappy Ubuntu Core, but this isn’t yet available pre-release. Your next stop would then probably follow ours with GNU Radio, and in particular its drag-and-drop GUI application GNU Radio Companion. This is nuts-and-bolts homebrew radio for the SDR age, just as analogue radio amateur homebrewers would solder their own radios while others bought shiny transceivers, so the SDR homebrewer can build their own devices using GNU Radio. It’s a package that’s beyond the scope of this review, but as an example when playing with the Mini it was fairly easy to cobble together a little GNU Radio receiver to pull in and extract the signals from a 433 MHz remote control transmitter we have in the house, and then regurgitate them through a 433MHz Baofeng antenna for the satisfying sight of a table lamp at the other end of the bench turning itself on. The Mini itself doesn’t intrude into this process beyond simply doing what it’s told once its communication with GNU Radio has been achieved, so experimenting further into the mechanics of decoding the bitstream itself became a matter of working through a set of tutorials and burning the midnight oil. The steep learning curve is amply offset by the satisfaction of playing with the instant gratification of radio building blocks without the pain of reworking any intricate soldering.

In transmission terms the maximum 100 mW output power is fairly modest for anyone used to amateur radio. But given that many applications for this board will involve the likes of sniffing for and responding to more local devices rather than seeking contacts from other continents this is something likely only to trouble radio amateurs without the wherewithal for a power amplifier. The twin antenna connectors will be somewhat annoying if you are used to a single one on a simplex transceiver, unless you are transmitting and receiving on different frequencies, of course.

A review of an SDR over a short period can not hope to cover all its many capabilities, so this one has been an impression of the Mini as a platform for experimentation and learning about how to use an SDR transceiver. But in just the time that it has been on the bench here, the Mini has opened a significant new vista over an RTL-SDR, and given a few months in which to play with GNU Radio will I am sure provide both some useful radio applications and a seriously interesting learning process.

Previous SDRs at the budget end of the market such as the HackRF have all remained somewhat expensive purchases, ones a typical radio amateur might have had difficulty concealing from their partner in the family accounts. With a price point that is almost edging into the realm of an impulse purchase, the Mini has the potential to become an SDR transceiver for everyone. If you have been holding back because of the price, maybe it’s time you gave it a look.

Unbricking A 3D Printer The Hard Way: By Writing a Bootloader

อังคาร, 03/13/2018 - 18:00

There’s a sinking feeling when a firmware upgrade to a piece of equipment goes wrong. We’ve all likely had this happen and  bricked a device or two. If we are lucky we can simply reapply the upgrade or revert to a previous version, and if we’re unlucky we have to dive into a serial debug port to save the device from the junk pile. But what happens when both those routes fail? If you are [Arko], you reverse-engineer the device and write your own bootloader for it.

The offending bricked object was a Monoprice MP Mini Delta 3D printer to which he was foolhardy enough to apply new firmware after seeing a friend’s machine taking it without issue. Finding the relevant debug interface on its main PCB he applied the firmware upgrade again, only to realise that in doing so he had overwritten its bootloader. The machine seemed doomed, but he wasn’t ready to give up.

What follows in his write-up is a detailed examination of the boot mechanism and memory map of an ARM Cortex M0 processor as found in the Monoprice’s STM32F070CB. We learn about vector tables for mapping important addresses of interrupts and execution points, and the mechanics of a bootloader in setting up the application it launches. This section is well worth a read on its own, even for those with no interest in bricked 3D printers.

In the end he had a working bootloader to which he appended the application firmware, but sadly when he powered up the printer there was still no joy. The problem was traced to the serial connection between the ARM doing the printer’s business and the ESP8266 running its display. After a brainstorm suggestion with a friend, a piece of code was found which would set the relevant registers to allow it to run at the correct speed.

So after a lot of work that resulted in this fascinating write-up, there was a working 3D printer. He suggests that mere mortals try asking Monoprice for a replacement model if it happens to their printers, but we’re extremely glad he persevered. Without it we would never have had this fascinating write-up, and would be the poorer without the learning experience.

This isn’t the first time we’ve brought you 3D printer bootloader trickery.