Enable Resizable BAR On Unsupported Motherboards

October 26, 2026 by Maya Posch 23 Comments

Recently [Rod Burlamaqui] released the arc-rebar project on GitHub, enabling Intel GPUs to work significantly more efficiently if the system’s mainboard does not support resizable BAR. It does require a Debian or Ubuntu installation and of course a supported Intel GPU.

Although the resizable base address register (ReBAR) feature has been part of the PCIe specification for a while, its use was quite limited until Intel released its Arc series of graphic cards. These use this feature to map much more of the GPU’s video RAM (VRAM) into the PC’s address space than the standard 256 MB, assuming that the system is capable of decoding addresses above 4 GB, i.e. allow for 64-bit BARs.

For GPU manufacturers like AMD and Nvidia this wasn’t so much of an issue as their GPU designs developed in a world where ReBAR didn’t exist, while Intel’s new GPU generations were designed with ReBAR as a core feature, which naturally cripples performance if the mainboard does not have it enabled during PCIe bus enumeration.

This initramfs-based fix runs before the GPU driver loads and performs the requisite BAR configuration. In testing with an Intel Arc B580 GPU on a 2015-era Intel Xeon mainboard the difference between the default and the fixed bandwidth was a bump from a pitiful 15 GB/s to a respectable 392 GB/s, showing how this one fix can breathe new life into older systems.

Practice Japanese On An Inkplate 4Tempera EInk Device

October 26, 2026 by Maya Posch 7 Comments

Learning a new natural language can be a daunting proposition at the best of times, with repetition and immersion generally considered to be the best ways to build up not only vocabulary but also that innate sense for grammar and cultural details that sneak into every spoken language. Flash cards are one way to help with vocabulary and sentence building, such as [Peter Hraska]’s Enkiplate project that uses the Inkplate 4Tempera being an interesting alternative to lugging a stack of cards with you.

Although the software also works in the browser, using the Inkplate or similar device means that you can keep it with you while it keeps track of your progress in learning the shown cards, with a starting pace of 12 cards per day to learn. It also shows you calendar items for that day and the weather using an online weather service.

Starting from basic kana, i.e. the two phonetic writing systems, the difficulty is slowly ramped up to cover kanji and then sentences. Due to the limitations of the 4Tempera’s ESP32-WROVER-E module’s local storage up to 16 flash cards can be stored at a time, with an application on a PC being necessary to obtain new cards.

The Fascinating World Of IrDA And Other Infrared Protocols

October 26, 2026 by Maya Posch 31 Comments

Infrared (IR) communication technologies are probably one of the most influential, yet also one of the least flashiest. The fact that IR communication tends to be highly directional and often limited to low data rate leads many people to scoff at it, deeming it barely worthy of more than making TV remotes work, perhaps along with some unloved industrial gear like the IR interface of electrical meters.

This is a shame, because TV remotes are a good example of why sometimes you want something that is directional, and anyone who has battled with Bluetooth pairing can attest to the value of things simply working by pointing it at the device. IR protocols also have the advantage of inherent privacy protection as walls and other obstacles will block the signal, unlike that of an exploitable Bluetooth device which happily advertises to your neighbors and passersby.

For reasons like the above – as well as their simplicity and hackability – IR protocols are worthy of a detailed look.

Continue reading “The Fascinating World Of IrDA And Other Infrared Protocols” →

Transforming A Tungsten Ditelluride Monolayer Into A Transistor

October 25, 2026 by Maya Posch 5 Comments

In the world of silicon semiconductors, the process of creating transistors and similar structures involves various rounds of modifications and additions in order to create the requisite functional layers. A less involved approach would simply create these structures in-situ, with research the past years having focused on transition-metal dichalcogenide (TMDC) monolayers to do exactly this. Recently [Seok Young Min] et al. reported (paywalled, Phys.org summary) on creating transistors in-situ in a tungsten ditelluride (WTe₂) monolayer.

By selectively changing parts of the top layer into tungsten oxide (WO_x) as an insulator and other sections into n-type WS₂ and p-type WSe₂ the researchers were able to create functional MOSFETs, without the normally requisite grafting on of different materials. An obvious advantage of this is that this can be done at an atomic scale, potentially achieving densities significantly higher than with industry standard silicon semiconductor technology.

WTe₂ is not the only TMDC that could be viable here, of course, with other researchers investigating the use of MoSe₂ for a similar purpose, as in this research by [N. Lu] et al. from 2014. This being the creation of 2D semiconductors, referring to the thin layers of these monolayer TMDCs, along with potentially other materials such as graphene.

A 3D Printed Marble Clock, But It’s Scrolling Text

October 25, 2026 by Maya Posch 9 Comments

With the topic of marble clocks having been quite well explored at this point, it raises the question of how easy it would be to take the basic principle and create a text display using black and white marbles. As [Ivan Miranda] found out in a recent marble text scroller project, this is far from easy.

The reason why a scrolling text display was picked comes down to not wanting to be limited to a fixed number of digits. This resulted in a round wheel design, with inner steel ball bearings and a stepper motor on both the wheel and an inner selector mechanism. These respectively align the marble channels and pick the right color of marbles to be dropped into any of the wheel’s slots, creating the right sequence of marbles for the target text.

Perhaps the most amazing thing about it is that it’s an absolutely massive structure, yet it’s all 3D printed and bolted together. It took a number of trial-and-error cycles, and debugging issues like the IR sensors getting confused by daylight, but it now mostly seems to work all right.

There are still some remaining issues, such as having to manually home the wheel before starting, and the ratio of black vs white marbles can cause unexpected gaps in the final text. Despite this the text is quite legible and definitely infinite.

Continue reading “A 3D Printed Marble Clock, But It’s Scrolling Text” →

That Weird 7-Pin S-Video Port On Old Laptops

October 24, 2026 by Maya Posch 21 Comments

Even though laptops from around the early 2000s came with just about every conceivable port on them, they still would often feature a somewhat unusual combined video output port. While at its core this was just a 4-pin analog S-video output, the three additional pins on the mini-DIN connector provided some more features. Of course, as [VWestlife] found out during his archaeological research, not every manufacturer used the same pinout here.

The naming for this specific port differs, with the name ‘S-video+’ appearing regularly, yet many descriptions glossing over the additional pins and only mentioning that it can be used with a 4-pin S-video connector. As it turns out, most manufacturers used roughly the same pinout, matching the shown Dell one. This adds composite output, along with two S/PDIF digital audio pins that could be routed out with an adapter into their full-sized ports.

Of course, the Apple PowerBook G4 had to be that exception again, with it omitting the audio pins and putting the composite signal on pin 5. This left the last two pins completely unused, but serving to completely confuse anyone who thought that they could get more out of the port with an adapter for those uncouth PC systems.

As to the remark at the end about how the transition to ‘just USB ports’ has made everything better, we’d challenge the average person to look at a random USB-C port and tell based on its appearance which standards it actually supports.

Continue reading “That Weird 7-Pin S-Video Port On Old Laptops” →

RepRapMicron Uses Fibre Optics To Print Tiny Benchy In Resin

October 23, 2026 by Maya Posch 9 Comments

The 0.5 mm Benchy made with the MicroRepRap UV head.

The RepRapMicron (also µRepRap) is pretty much the microscopic take on what RepRap did for more macroscale manufacturing, with the most recent innovation being a UV print head, called the PIKA UV Head. What this does is use off-the-shelf optical fiber and UV LED modules to create 3D structures in-situ in a UV resin, allowing for pretty small structures to be printed, down to a resolution of about 9 µm.

More photos of prints can be found on the blog page with links to YouTube videos. It’s naturally somewhat tricky to get clean photographs of a 3D print that’s small enough to lose forever if you so much as sneeze or breathe too loudly.

For the UV head assembly a single mode fiber optical cable was used in the form of a regular patch cord that got trimmed a bit with a hacksaw. This was used in combination with a “3W” UV LED module, which may or may not be its true rating, but it was definitely able to cure the SLA resin. The used resin was regular eSun Standard Resin.

Afterwards you have to do the typical SLA post-processing, including cleaning off of liquid resin – both the part and fiber – and curing the part. So far results are pretty decent, with overhangs still being a weak spot that will be addressed in future revisions.