Debugging And Analyzing Real-Mode 16-Bit X86 Code With Fresh Bread

March 28, 2023 by Maya Posch 7 Comments

Running a debugger like gdb with real-mode 16-bit code on the x86 platform is not the easiest thing to do, but incredibly useful when it comes to analyzing BIOS firmware and DOS software. Although it’s possible to analyze a BIOS image after running it through a disassembler, there is a lot that can only be done when the software is running on the real hardware. This is where [Davidson Francis] decided that some BREAD would be useful, as in BIOS Reverse Engineering & Advanced Debugging.

What BREAD does is provide some injectable code that with e.g. a BIOS replaces the normal boot logo with the debugger stub. This stub communicates with a bridge via the serial port, with the gdb client connecting to this bridge. Since DOS programs are also often 16-bit real-mode, these can be similarly modified to provide light-weight in-situ debugging and analysis. We imagine that this software can be very useful both for software archaeology and embedded purposes.

Thanks to [Rodrigo Laneth] for the tip.

Europe’s Proposed Right-To-Repair Law: A Game Changer, Or Business As Usual?

March 27, 2023 by Maya Posch 145 Comments

Recently, the European Commission (EC) adopted a new proposal intended to enable and promote the repair of a range of consumer goods, including household devices like vacuum cleaners and washing machines, as well as electronic devices such as smartphones and televisions. Depending on how the European Parliament and Council vote in the next steps, this proposal may shape many details of how devices we regularly interact with work, and how they can be repaired when they no longer do.

As we have seen recently with the Digital Fair Repair Act in New York, which was signed into law last year, the devil is as always in the details. In the case of the New York bill, the original intent of enabling low-level repairs on defective devices got hamstrung by added exceptions and loopholes that essentially meant that entire industries and types of repairs were excluded. Another example of ‘right to repair’ being essentially gamed involves Apple’s much-maligned ‘self repair’ program, that is both limited and expensive.

So what are the chances that the EU will succeed where the US has not?

Continue reading “Europe’s Proposed Right-To-Repair Law: A Game Changer, Or Business As Usual?” →

Caterpillar-Like Soft Robot With Distributed Programmable Thermal Actuation

March 26, 2023 by Maya Posch 7 Comments

Researchers at North Carolina State University have created a soft robot that moves in a distinctly caterpillar-like manner. As detailed in the research paper in Science Advances by [Shuang Wu] and colleagues, the robot they developed consists of a layer of liquid crystalline elastomers (LCE) and polydimethylsiloxane (PDMS) with embedded silver nanowire that acts as a heater.

The LCE is hereby designed as a thermal bimorph actuator, using a distinct thermal expansion coefficient between the LCE and PDMS sides to create a highly controllable deformation and thus motion. Since the nanowire is divided into sections that can be individually heated, the exact deformation can be quite tightly controlled, enabling the crawling motion.

(A) Schematics of the forward locomotion of a caterpillar. (B) Schematics of the reverse locomotion of a caterpillar. (C) Snapshots of the crawling robot in one cycle of actuation for reverse locomotion. (D) Snapshots of the crawling robot in one cycle of actuation for forward locomotion. (E) infrared image of the crawling robot with 0.05-A current injected in channel 1 and the tilted view of the crawling robot. (F) Infrared image of the crawling robot with 30-mA current injected in channel 2 and the corresponding tilted view of the crawling robot. (Credit: Shuang Wu, et al. (2023))

As can be seen in the video below, the motion is fairly rapid and quite efficient, as well as decidedly caterpillar-like. Although the current prototype uses external control wires that supply the current, it might be possible to integrate a power supply and control circuitry in a stand-alone robot. Since the heater works on low voltage (5 V) and relatively little power is required, this would seem to make stand-alone operation eminently possible.

Continue reading “Caterpillar-Like Soft Robot With Distributed Programmable Thermal Actuation” →

Recreating The ZX Spectrum Unboxing Experience By Manufacturing A New Boxed One

March 26, 2023 by Maya Posch 7 Comments

Why scour the internet for a rare-as-hen’s-teeth new in box ZX Spectrum computer when you can instead order up some parts, assemble a basically all new ZX Spectrum along with the box, instruction manuals and more?

That seems to have been the reasoning behind [Lost Retro Tapes] when they decided to do exactly that. Along with the announcement of the completion on Reddit, the website details the BOM and sourcing the components.

For the mainboard, an existing, redrawn ZX Spectrum 48 Issue 3B PCB was found and ordered from PCBWay. As a UK-based entity, many of the other components were sourced from retro computing shops around the UK, but with all but the LM1889N IC being available for new or with currently produced alternative, it should be viable to source them locally.

Perhaps most impressive was the creation of the box (unfortunately not detailed on the website at this point), and having the manuals (system and BASIC) professionally printed and bound. Along with a few other bits and pieces, including a tape recorder and fresh Horizons tape, the total price tag came to around £412.

Thanks to [Lee Hodgson] for the tip.

Combining Acoustic Bioprinting With Raman Spectroscopy For High-Throughput Identification Of Bacteria

March 22, 2023 by Maya Posch 6 Comments

Rapidly analyzing samples for the presence of bacteria and similar organic structures is generally quite a time-intensive process, with often the requirement of a cell culture being developed. Proposed by Fareeha Safir and colleagues in Nano Letters is a method to use an acoustic droplet printer combined with Raman spectroscopy. Advantages of this method are a high throughput, which could make analysis of samples at sewage installations, hospitals and laboratories significantly faster.

Raman spectroscopy works on the principle of Raman scattering, which is the inelastic scattering of photons by matter, causing a distinct pattern in the thus scattered light. By starting with a pure light source (that is, a laser), the relatively weak Raman scattering can be captured and the laser light filtered out. The thus captured signal can be analyzed and matched with known pathogens. Continue reading “Combining Acoustic Bioprinting With Raman Spectroscopy For High-Throughput Identification Of Bacteria” →

Fresh PCBs For The Quickshot II And II Plus Joysticks

March 21, 2023 by Maya Posch 13 Comments

The Quickshot II was released by Spectravideo in 1983 for the Commodore 64 and compatible systems, with the Quickshot II Plus following the next year. After decades of regular use, it’s quite understandable that these old-timers may be having some functional issues, but as long as the plastic parts are still good, [Stephan Eckweiler]’s replacement PCBs may be just the thing that these joysticks need to revitalize them for another few decades.

What may be a matter of taste is that these replace the nice tactile clicky switches on the QS II Plus with SMD push buttons, but compared to the stamped metal ‘button’ construction of the original QS II, the new board is probably a major improvement. As for the BOM, it features two ICs: a 74LS00 latch and NE555 timer, along with the expected stack of passives and switches, both through-hole and SMD.

The PCB contains break-off boards for the switches within the joystick itself, requiring a bit of wiring to be run to the main PCB before soldering on the DE-9 connector and connecting the joystick for a test run to a Commodore 64. All one needs now is a 3D printable enclosure version to create more QS II joysticks for some multiplayer action.

Modifying Artwork With Glaze To Interfere With Art Generating Algorithms

March 20, 2023 by Maya Posch 48 Comments

With the rise of machine-generated art we have also seen a major discussion begin about the ethics of using existing, human-made art to train these art models. Their defenders will often claim that the original art cannot be reproduced by the generator, but this is belied by the fact that one possible query to these generators is to produce art in the style of a specific artist. This is where feature extraction comes into play, and the Glaze tool as a potential obfuscation tool.

Developed by researchers at the University of Chicago, the theory behind this tool is covered in their preprint paper. The essential concept is that an artist can pick a target ‘cloak style’, which is used by Glaze to calculate specific perturbations which are added to the original image. These perturbations are not easily detected by the human eye, but will be picked up by the feature extraction algorithms of current machine-generated art models. Continue reading “Modifying Artwork With Glaze To Interfere With Art Generating Algorithms” →