Faking Bluetooth LE With An NRF24L01+ Module

January 11, 2024 by Maya Posch 11 Comments

Despite the name, Bluetooth Low Energy (BLE) has very little to do with the original Bluetooth, other than its use of the same 2.4 GHz frequencies. This is where [Dmitry] got the idea to use a 2.4 GHz nRF24L01+ module to implement his very own BLE device, without the typical BLE chipset. This should be easy, since this popular IC supports GFSK modulation, 1 MHz channels and the 1 MBit data rate of BLE.

Despite of how simple BLE seems to implement, [Dmitry] quickly came across a range of issues due to limitations of the nRF24L01+. These include no support for a 24-bit CRC, a too sluggish PLL cycling for BLE’s frequency hopping, and as the coup de grâce, a lack for incoming data packets larger than 32 bytes — which destroyed any hope of accepting incoming connections.

Unperturbed, [Dmitry] set to work implementing what would work on this IC: broadcasting BLE packets. In the article he covers the entire code (in C) that allows the nRF24L01+ to send broadcast packets and any BLE-supporting device that’s listening to receive them. Admittedly not as useful as having a fully functional BLE stack, but good enough for broadcasting something like sensor data. It also raises the question of which alternative released in the intervening decade to the venerable nRF24L01+ might fill in the missing features, without making a dedicated BLE IC (or ESP32 variant) look more cost-effective.

It’s always a good day when a new project from [Dmitry] hits the tip line. We’ve previously covered his impressive efforts to add more RAM to the RP2040, and his business card that can boot Linux on an ATSAMD21.

The Hobbes OS/2 Archive Will Shut Down In April

January 10, 2024 by Maya Posch 27 Comments

The Hobbes OS/2 Archive is a large collection of OS/2 software that has been publicly available for many years, even as OS/2 itself has mostly faded into obscurity. Yet now it would appear that the entity behind the Hobbes OS/2 Archive, the Information & Communication Technologies department at the New Mexico State University, has decided to call it quits — with the site going permanently offline on April 15th, 2024.

Fortunately, from a cursory glance around the comment sections over at Hacker News and other places, it seems that backup efforts have already been made, and the preservation of the archive’s contents should be secure at this point in time. Regardless, it is always a shame to lose such a central repository, especially since IBM’s OS/2 operating system is still anything but dead. Whether for hobbyist, industrial or commercial use, there is still a vibrant community around today, as we noted in 2019 already in relation to the NYC’s subway system.

Beyond downloaded copies and boxed CDs bought on EBay, you can even get a modernized version of OS/2 called ArcaOS, which even comes with commercial support. Whatever the fate is of the Hobbes OS/2 Archive’s data, we hope it finds a loving new home somewhere.

Not Dead Yet: Microsoft Peripherals Get Licensed To Onward Brands

January 10, 2024 by Maya Posch 33 Comments

After Microsoft announced in April of 2023 that they’d cease selling branded peripherals – including keyboards and mice – as part of its refocusing on Surface computers and accessories, there was an internet-wide outcry about this demise. Yet now it would seem that Microsoft has licensed the manufacturing of these peripherals to Incase, who will be selling a range of ‘Designed By Microsoft’ peripherals starting in 2024. Incase itself is a brand owned by Onward Brands, which is the portfolio manager for Incase and other brands.

Although Microsoft has been selling peripherals since the 1980s (with the Microsoft Mouse appearing in 1983), it seems that we now have to rely on this new company that is said to use the same suppliers as Microsoft did. As for what we can expect to see return with Incase, it’s effectively the same assortment of items that Microsoft was selling at the beginning of 2023, so we will likely not see the return of the Natural 4000 or other peripherals that saw their life cut short before this.

If Incase does manage to relaunch these products this year, which items would you be most interested in purchasing, and how many dozens of those did you manage to stock up on in April when the news broke?

How To Build A Fully Offline Smart Home, Or Why You Should Not

January 9, 2024 by Maya Posch 91 Comments

So-called ‘smart home’ appliances and gadgets have become an ever-more present thing the past years, with nary a coffeemaker, AC unit or light bulb for sale today that doesn’t have an associated smartphone app, cloud service and/or subscription to enable you to control it from the beach during your vacation, or just set up automation routines to take tedium out of your busy schedule. Yet as much as [Calvin Wankhede] loves home automation, he’d very much like for it to not stop working the moment his internet connection goes down, or the company running the service goes bankrupt. This is where his journey to create an off-line alternative smart home based around Home Assistant and other (open) software began.

Although Home Assistant (HA) itself has become significantly easier to use, what becomes readily apparent from [Calvin]’s journey is that setting up and managing your own smart home infrastructure is a never-ending project. A project that involves finding compatible hardware that can tie into HA, whether or not without reflashing the firmware, resolving configuration issues and other assorted fun. If you are into this kind of thing, it is of course a blast, and it’s a good feeling when it finally all works.

Unfortunately, interoperability across smart home and similar IoT devices is still a far-off dream, even with the introduction of Thread and Matter (which incidentally are among the worst product names to search for, period), as Matter’s uptake is pretty abysmal. This thus leaves off-line smart homes mostly as the domain of the tech-inclined in search of a hobby.

X1Plus: Open Source Bambu Lab X1 Firmware

January 9, 2024 by Maya Posch 35 Comments

Recently [Michael] over at the [Teaching Tech] YouTube channel got access to the X1Plus firmware, and takes us through what it may mean for Bambu Lab X1 owners. X1Plus is alternative firmware for the Bambu Lab X1 FDM 3D printer that was developed by X1 owners who felt that there were some features that they were missing, such as a detailed report on automatic bed leveling, input shaping calibration response graphs and more.

Perhaps most interesting is that this firmware does not replace the Bambu Lab firmware, but rather runs completely from a microSD card that’s inserted into the display’s SD card reader. This means that only the bootloader of the printer’s boot medium is changed, and the printer thus retains the ability boot to the OEM firmware as needed. Whether you want to try it on your own X1 depends on a few factors, first of all being that it only works with the OEM firmware up to and including version 1.7.0.

Since the bootloader modification relies on an exploit that was patched in newer firmware, a lot depends on whether Bambu Lab allows such tinkering, much like Prusa does with the Mini printer, or allows flashing of older firmware which would enable the exploit on newer X1 printers. Depending on Bambu Lab’s response, the imminent public release of this open source firmware may as a result run into some pretty big hurdles.

Continue reading “X1Plus: Open Source Bambu Lab X1 Firmware” →

How To Refrigerate With Urine

January 9, 2024 by Maya Posch 13 Comments

It’s often said that the best science experiments are the ones which do not require any special devices or ingredients, which makes the use of what naturally comes out of one’s body clearly one of the winners. It’s also the beginning of yet another [Hyperspace Pirate] chemistry video that’s both fascinating and unforgettable — this time introducing a considerable collection of urine, and the many uses of the urea in it, including its use for refrigeration.

The respective cooling effect of a variety of compounds in solution. (Credit: Hyperspace Pirate)

As icky as this may sound, it doesn’t even rank in the top ten of quaint things people have historically done with urine, so extracting urea from it is rather benign. This is performed by adding sodium hydroxide to the starting component after heating, which creates gaseous ammonia (NH₃) which was then condensed into its liquid (dissolved) form. In order to create the target compound – being ammonium nitrate – nitric acid (HNO₃) had to be created first.

For this the older, but cheaper and easier Birkeland-Eyde process was used. This uses high-voltage electrical arcs to break down the nitrogen and oxygen in the air and cause the formation of nitric oxide (NO), that subsequently reacts with atmospheric oxygen to form nitrogen dioxide (NO₂). Running the NO₂ through water then creates the desired HNO₃, which can be combined with the ammonia solution to create ammonium nitrate. The resulting solution was then evaporated into solid ammonium nitrate, to use it in an aluminium cooling cylinder, with freshly added water.

This is the simplest way to use the cooling effect of such solutions (pictured), but the benefit of ammonium nitrate over the original urea seems minimal. The low efficiency of this cooling approach means that the next use of urine will involve a much more efficient vapor-absorption cycle, which we’re sure everyone is squeezing their legs together for in anticipation.

We’ve been covering the refrigeration experiments [Hyperspace Pirate] has been conducting for some time now. If you’re into the science of making things cold check out how seashells can be turned into dry ice, or what goes into building a home cryocooler.

Continue reading “How To Refrigerate With Urine” →

World’s First Precision Lathe: Indispensable When Constructing The Antikythera Mechanism

January 7, 2024 by Maya Posch 27 Comments

The precision lathe with the hooks, the bowstring, and vise visible as material is being processed. (Credit: Clickspring)

We commonly tend to associate lathes with the Industrial Revolution, when metalworking shifted largely from blacksmiths to machinists, but the use of lathes is much older than that. As [Chris] over at the Clickspring YouTube channel demonstrates in a recent video, small precision lathes were exceedingly common in the Ancient World. Not only is there ample historical evidence of them being used as far back as 1300 BCE in Ancient Egypt, but they’re also the most optimal way to get perfectly round pins and other, more intricate shapes that would be an absolute nightmare to create with just some metal files and chisels.

In the video, [Chris] uses two metal hooks, bent in a ninety-degree angle and clamped down in a vise, tapering towards each other into points. A bow string around a round piece of wood is used to bootstrap a more permanent retention element and bushing for the bow string as it is drawn over the wood to rotate it. Subsequent material that has to be worked on in the lathe is then clamped between the two points. This way, using basic materials that have been around for thousands of years and some muscle power, it’s possible to create a small lathe that can be used to create perfectly symmetrical shapes, such as those used in the construction of the Antikythera Mechanism, which [Chris] has been rebuilding for the past years, using only period-correct tools. He’s learned a lot about the mechanism in the process.

Continue reading “World’s First Precision Lathe: Indispensable When Constructing The Antikythera Mechanism” →