New Part News: Raspberry Pi Cuts Out The Middleman

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.

Electromyography

Electromyography Hack Chat

Join us on Wednesday, January 19 at noon Pacific as we kick off the 2022 Hack Chat season with the Electromyography Hack Chat with hut!

It’s one of the simplest acts most people can perform, but just wiggling your finger is a vastly complex process under the hood. Once you consciously decide to move your digit, a cascade of electrochemical reactions courses from the brain down the spinal cord and along nerves to reach the muscles fibers of the forearm, where still more reactions occur to stimulate the muscle fibers and cause them to contract, setting that finger to wiggling.

join-hack-chatThe electrical activity going on inside you while you’re moving your muscles is actually strong enough to make it to the skin, and is detectable using electromyography, or EMG. But just because a signal exists doesn’t mean it’s trivial to make use of. Teasing a usable signal from one muscle group amidst the noise from everything else going on in a human body can be a chore, but not an insurmountable one, even for the home gamer.

To make EMG a little easier, our host for this Hack Chat, hut, has been hard at work on PsyLink, a line of prototype EMG interfaces that can be used to detect muscle movements and use them to control whatever you want. In this Hack Chat, we’ll dive into EMG in general and PsyLink in particular, and find out how to put our muscles to work for something other than wiggling our fingers.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, January 19 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Continue reading “Electromyography Hack Chat”

Old Firewall Reborn As Retro PC

We like projects where old gear is given a new life. [Splashdust] has a twenty-year old business firewall that’s build like a tank. He cracks it open and finds a complete x86 embedded motherboard inside, and sets off to restore it and turn it into a retro gaming computer (see the video from his Odd & Obsolete YouTube channel below the break).

This business firewall and router box is from a small Swedish firm Clavister, part of their S-Series from the early 2000s. The motherboard appears to be a generic one used in other equipment, and is powered by a VIA Eden ESP 4000 running at 400 MHz. The Eden line of x86 processors were low-power chips targeting embedded applications. The graphics chip is a Twister T by S3 Graphics which was purchased by VIA in 2000. After replacing the electrolytic capacitors, and making a few cables, [Splashdust] pops in a PCI sound card and boots up into Windows 98 from a CF card (we like the compact PCB vise he uses).

In two follow-up videos (here and here), he builds an enclosure (instructions on Thingiverse) and tries out several other operating systems. He was able to get the Tiny Core Linux distribution running with the NetSurf browser, but failed to get Windows 2000 or XP to work. Returning to Windows 98, he tweaks drivers and settings and eventually has a respectable retro-gaming computer for his efforts. The next time you’re cleaning out your junk bins, have a peek inside those pizza-box gadgets first — you may find a similar gem.

Continue reading “Old Firewall Reborn As Retro PC”

3D Printed Magnetic Switches Promise Truly Custom Keyboards

While most people are happy to type away at whatever keyboard their machine came with, for the keyboard enthusiast, there’s no stone to be left unturned in the quest for the perfect key switch mechanism. Enter [Riskable], with an innovative design for a 3D printed mechanism that delivers near-infinite adjustment without the use of springs or metallic contacts.

The switching itself is performed by a Hall effect sensor, the specifics of which are detailed in a second repository. The primary project simply represents the printed components and magnets which make up the switch mechanism. Each switch uses three 4 x 2 mm magnets, a static one mounted on the switch housing and two on the switch’s moving slider. One is mounted below the static magnet oriented to attract it, while the other is above and repels it.

With this arrangement the lower magnet provides the required tactility, while the upper one’s repulsive force replaces the spring used in a traditional mechanism. [Riskable] calls it the magnetic separation contactless key switch, but we think “revolutionary” has a nicer ring to it.

The part which makes this extra-special is that it’s a fully parametric OpenSCAD model in which the separation of the magnets is customisable, so the builder has full control of both the tactility and return force of the keys. There’s a video review we’ve posted below that demonstrates this with a test keypad showing a range of tactility settings.

We have a resident keyboard expert here at Hackaday in the shape of our colleague [Kristina Panos], whose Keebin’ With Kristina series has introduced us to all that is interesting in the world of textual input. She plans on taking a keyboard made of these clever switches on a test drive, once she’s extruded the prerequisite number of little fiddly bits.

Continue reading “3D Printed Magnetic Switches Promise Truly Custom Keyboards”

Hack The Web Without A Browser

It is a classic problem. You want data for use in your program but it is on a webpage. Some websites have an API, of course, but usually, you are on your own. You can load the whole page via HTTP and parse it. Or you can use some tools to “scrape” the site. One interesting way to do this is woob — web outside of browsers.

The system uses a series of backends tailored at particular sites. There’s a collection of official backends, and you can also create your own. Once you have a backend, you can configure it and use it from Python. Here’s an example of finding a bank account balance:

>>> from woob.core import Woob
>>> from woob.capabilities.bank import CapBank
>>> w = Woob()
>>> w.load_backends(CapBank)
{'societegenerale': <Backend 'societegenerale'>, 'creditmutuel': <Backend 'creditmutuel'>}
>>> pprint(list(w.iter_accounts()))
[<Account id='7418529638527412' label=u'Compte de ch\xe8ques'>,
<Account id='9876543216549871' label=u'Livret A'>,
<Account id='123456789123456789123EUR' label=u'C/C Eurocompte Confort M Roger Philibert'>]
>>> acc = next(iter(w.iter_accounts()))
>>> acc.balance
Decimal('87.32')

The list of available backends is impressive, but eventually, you’ll want to create your own modules. Thankfully, there’s plenty of documentation about how to do that. The framework allows you to post data to the website and easily read the results. Each backend also has a test which can detect if a change in the website breaks the code, which is a common problem with such schemes.

We didn’t see a Hackaday backend. Too bad. There are, however, many application examples, both console-based and using QT. For example, you can search for movies, manage recipes, or dating sites.

Of course, there are many approaches possible to this problem. Maybe you need to find out when the next train is leaving.

A Dodgy Dial Gets A Teardown And Some Oil

The pulse-dial telephone and its associated mechanical exchange represents the pinnacle of late-19th and early-20th century electromechanical technology, but its vestiges have disappeared from view with astonishing rapidity. [Matthew Harrold] is a telecoms enthusiast who’s been kind enough to share with us the teardown and refurbishment of that most signature of pulse-dial components, a telephone dial. In this case it’s on a rather unusual instrument, a British GPO outdoor phone that would have been seen in all kinds of industrial and safety installations back in the day and can probably still be found in the wild today if you know where to look.

The teardown soon identifies a dial that runs very slowly and is sorely in need of a clean. There follows a detailed part-by-part dismantling of the dial mechanism, followed by a careful clean, polish, and reassembly. He notes that a previous owner had used grease to lubricate it, probably the reason for its slow operation.

The result is a smoothly running dial and a refurbished phone that would probably last another half-century or more before needing more maintenance. It’s enough to make others who’ve experimented with pulse dial phones very envious.

Open Source Replacement For EzCAD

[Bryce] obtained a fiber laser engraver to use for rapid PCB prototyping last Fall. But he was soon frustrated by the limitations of the standard EzCAD software that typically comes with these and similar devices — it is proprietary, doesn’t have features aimed at PCB manufacturing, only runs on Windows, and is buggy. As one does, [Bryce] decided to ditch EzCAD and write his own tool, Balor, named after the King of the Fomorians.

The controller board in [Bryce]’s machine is a Beijing JCZ LMCV4-FIBER-M board, containing an Altera FPGA and a Cypress 8051 USB controller. So far, he hasn’t needed to dump or modify the FPGA or 8051 code. Instead, he sorted out the commands by just observing the USB operations as generated by a copy of EzCAD running know operations. A lot of these engraving systems use this control board, but [Bryce] want’s to collect data dumps from users with different boards in order to expand the library.

Balor is written in Python and provides a set of command line tools aimed at engineering applications of your engraver, although still supporting regular laser marking as well. You can download the program from the project’s GitLab repository. He’s running it on Linux, but it should work on Mac and Windows (let him know if you have any portability issues). Check out our write-up from last year about using these lasers to make PCBs. Are you using a laser engraver to make rapid prototype boards in your shop? Tell us about your setup in the comments.