TechyMagThings

ST’s VL53L5CX is a very small 8×8 grid ranging sensor that can perform distance measurements at a distance of up to 4 meters. In a recent video,[Henrique Ferrolho] demonstrated that this little sensor can also be used to perform a 3D scan of a room. The sensor data can be combined with an IMU to add orientation information to the scan data. These data streams are then combined by an ESP32 MCU that streams the data as JSON to a connected computer.

Of course, that’s just the heavily abbreviated version, with the video covering the many implementation details that crop up when implementing the system, including noise filtering, orientation tracking using the IMU and a variety of plane fitting algorithms to consider.

Note that ST produces a range of these Time-of-Flight sensors that are more basic, such as the VL53VL0X, which is a simple distance meter limited to 2 meters. The VL53L5CX features the multizone array, 4-meter distance range, and 60 Hz sampling speed features that make it significantly more useful for this 3D scanning purpose.

The Python-based viewer that runs on the PC can be found on GitHub, along with the ESP32 firmware.

One of the joys of browsing secondhand shops is the possibility of finding old, perhaps restorable or hackable, electronics at low prices. Admittedly, they usually seem to be old flat-screen TVs, cheap speakers, and Blu-ray players, but sometimes you find something like the Dash, an educational toy robot. When [Jonathan] came across one of these, he decided to use it as a turtle robot. However, he found the available Python libraries insufficient, and improving on them required some reverse-engineering.

While [Jonathan] was rather impressed with the robot as it was – it had a good set of features, and thought had clearly been put into the design – he wanted a more open way to control it. There was already a quite useful, official Python program to control the robot over a BLE connection, but it only worked with Python 2 on OS X ([Jonathan] theorizes that it might have been written as a development tool, open-sourced, and not diligently supported afterwards). There were also a few third-party libraries ported to Python 3, but they all seemed to be missing some important features.

All the newer libraries were limited because the official library passed commands to an OS X binary, which handled the actual communication, so anyone wanting to do everything in Python would have to reverse-engineer the communications protocol. [Jonathan] therefore used Ghidra to decompile the binary. He first found the JSON structure used for message data, followed by a function that reads command information and sets up packets, and a mapping between Python command names and command IDs. Once he found the section that creates packets from data, he was able to port the program to Python 3. Interestingly, examining the binary revealed some previously unknown commands that appear to be capable of defining autonomous behavior.

We’ve previously seen Ghidra used on devices ranging from a camera to a router; if you’d like to learn more, there’s a HackadayU course on it.

Are you in the mood for a retrocomputing deep dive into the Scriptovision Super Micro Script? It was a Canadian-made vintage video titler from the 80s, and [Cameron Kaiser] has written up a journey of repair and reverse-engineering for it. But his work is far more than just a refurbish job; [Cameron] transforms the device into something not unlike 8-bit homebrew computers of the era, able to upload and run custom programs with a limited blister keypad for input, and displaying output on a composite video monitor.

A video titler like the Super Micro Script gave people the ability to display bitmapped images (like text or simple graphics) onto a video stream electronically. A standalone device, under the hood, it uses a 6502 as CPU and a Motorola 6847 VDG video chip. [Cameron] observes that architecture-wise, it actually had a lot in common with early 8-bit home computers. Sure, it performed only one “job” but that really had more to do with its restrictive firmware than anything else.

[Cameron] obtained a used unit and repaired it, reverse-engineered the scrambled address and data lines (an anti-cloning and anti-tampering measure), and converted it into something for which he could write his own software and run his own programs. As for uploading those programs? A bit-banged serial port on I/O borrowed from the blister keypad, running at a frankly quite respectable 19.2 kbps.

We hope you’re intrigued, because [Cameron] has one more surprise: he created a MAME emulator for the Super Micro Script called SMSBUG. Originally created to make software development easier, its existence also means anyone can join in on the vintage computing fun. The emulator, along with other handy utilities and info, is available on GitHub.

The lovely thing about the x86 architecture is its decades of backwards compatibility, which makes it possible to run 1990s operating systems on modern-day hardware, with relatively few obstacles in the way. Recently [Yeo Kheng Meng] did just that with Windows 98 SE on a 2020 ThinkPad P12s Gen 1, booting it alongside Windows 11 and Linux from the same NVMe drive.

Naturally, after previously getting MS-DOS 6.22 from 1994 running on a 2020 ThinkPad X13, the step to doing the same with Windows 98 SE wasn’t that large. The main obstacles that you face come in the form of UEFI and hardware driver support.

Both ThinkPad laptops have in common that they support UEFI-CSM mode, also known as ‘classical BIOS’, as UEFI boot wasn’t even a glimmer yet in some drunk engineer’s eye when Win98 was released. After this everything is about getting as many hardware drivers scrounged together as possible.

[Yeo] ended up having to bodge on a USB 2.0 expansion card via a Thunderbolt dock as Win98 doesn’t have xHCI (USB 3.0) support. With that issue successfully bodged around using a veritable tower of adapters, installing Windows 98 was as easy as nuking Secure Boot in the BIOS, enabling UEFI-CSM along with Thunderbolt BIOS assist mode and disable Kernel DMA protection.

Because UEFI-CSM implementations tend to be buggy, the CREGFIX DOS driver was used to smooth things over. Another issue is the same that we chuckled about back in the day, as Windows 98 cannot address more than 512 MB of RAM by default. Fortunately patches by [Rudolph Loew] helped to fix this and some other smaller issues.

Unfortunately neither Intel nor NVIDIA have released Win98 drivers for quite some time, so there’s no graphics acceleration beyond basic VESA support and the SoftGPU driver. Disk access goes via the BIOS too rather than using an NVMe driver, so it’s not as zippy as it could be, but for Win9x it’s quite usable.

Finally ACPI wasn’t recognized by Win98, but it’s only fair to blame that on the complete flaming train wreck that is ACPI rather than anything to do with Windows. This particular issue was worked around by configuring the BIOS to support S3 power state and with that making Win98 happy again.

It’s honestly quite a shame that UEFI-CSM is largely ignored by new systems, as it makes installing even Windows 7 basically impossible, and thus creating probably the largest split within the x86 ecosystem since the arrival of AMD64/x86_64.

Many things about diamonds seem eternal, including the many engineering problems related to making them work as a silicon replacement in semiconductor technology. Yet much like a diamond exposed to a stream of oxygen-rich air and a roughly 750°C heat source, time will eventually erase all of them. As detailed in a recent [Asianometry] video, over the decades the challenges with creating diamond wafers and finding the right way to dope pure diamond have been slowly solved, even if some challenges still remain today.

Diamond is basically the exact opposite as silicon when it comes to suitability as a semiconductor material, with a large bandgap (5.5 eV vs the 1.2 of silicon), and excellent thermal conductivity characteristics. This means that diamond transistors are very reliable, albeit harder to switch, and heat produced during switching is rapidly carried away instead of risking a meltdown as with silicon semiconductors.

Unlike silicon, however, diamond is much harder to turn into wafers as you cannot simply melt graphite and draw perfectly crystallized diamond out of said molten puddle. The journey of getting to the state-of-the art soon-to-be-4″ wafers grown on iridium alongside the current mosaic method is a good indication of the complete pain in the neck that just this challenge already is.

Doping with silicon semiconductors is done using ion implantation, but diamond has to be special and cannot just have phosphorus and boron implanted like its sibling. The main challenge here is that of availability of charge carriers from this doping, with diamond greedily hanging on to these charge carriers unless you run the transistor at very high temperatures.

Since you can only add so much dopant to a material before it stops being that material, a more subtle solution was sought. At this point we know that ion implantation causes damage to the diamond lattice, so delta-doping – which sandwiches heavily doped diamond between non-doped diamond – was developed instead. This got P-type transistors using boron, but only after we pacified dangling carbon electron bonds with hydrogen atoms and later more stable oxygen.

State-of-the art switching with diamond transistors is currently done with MESFETs, which are metal-semiconductor field-effect transistors, and research is ongoing to improve the design. Much like with silicon carbide it can take a while before all the engineering and production scaling issues have been worked out. It’s quite possible that we’ll see diamond integrated into silicon semiconductors as heatsinks long before that.

Assuming we can make diamond work for semiconductor transistors, it should allow us to pack more and smaller transistors together than even before, opening up many options that are not possible with silicon, especially in more hostile environments like space.

While it is fun to get toys that look like your favorite science fiction props, it is less fun when the electronics in them don’t measure up to the physical design. [Steve Gibbs] took a Hasbro R2D2 toy robot and decided to give it a brain upgrade along with enhanced sensors. You can see a video of the robot doing its thing and some build details below.

In this case, the toy from Hasbro was not working at all, so [Steve] saved it from the dumpster. Instead of a repair, he decided to just gut it and rebuild it with modern electronics. The ultrasonic sensor on the forward toe is a dead giveaway.

The robot responds to voice commands better than the original and can play sound effects and clips from Star Wars. You can also control the robot with a phone app. The new or upgraded sensors include microphones, a PIR sensor, a photoresistor to sense light, a smoke and CO₂ sensor, a computer vision camera, and, of course, the ultrasonic range finder.

Some motors and the original speaker are in use, but R2 now sports additional LEDs and servos. All the extras required some surgery on the plastic body. Instead of regular batteries, the ‘bot now uses a LiPo battery, so the old battery compartment was cut out to make more room.

Even if you aren’t a die-hard Star Wars fan, this is a fantastic project, and May the 4th is right around the corner. These toys aren’t cheap, but if you can score one with bad electronics, you might be able to find something cheap or — like Steve — even free.

These toys are popular hacking targets. Now [Steve] needs a pit droid.

It’s a bit ironic that an Atari 2600 game based on Raiders of the Lost Ark — a movie about archaeology — is now the subject of its own archaeological expedition as [Dennis Debro] and [Halkun] spent time reverse-engineering the game. Luckily, they shared their findings, so you can enjoy it the same way you can visit a king’s tomb without having to discover it and dig for it. If you don’t remember the game, you might enjoy the demo from [Speedy Walkthroughs] in the video below.

If you are only used to modern software, you might think this is little more than someone dumping the program code and commenting it. However, on these old, limited systems, you have to really understand the actual architecture because there are so many things you have to manage that are specific to the hardware.

For example, the game has two 4K ROM banks that use a strange switching mechanism. The entire game is built around the NTSC television signal. Everything is oriented toward generating the 60 Hz frame rate. Game logic runs during the vertical blanking and over-scan sections to prevent strange visible artifacts due to software running.

This is a fascinating look inside game coding as it existed around 1982. Of course, you can also run everything using emulation. Usually, our reverse engineering is more hardware-related. But we do love these old games, too.