Zork Zcode Interpreters Appear Out Of Nowhere

Some of our readers may know about Zork (and 1, 2, 3), the 1977 text adventure originally written for the PDP-10. The game has been public domain for a while now, but recently, the interpreters for several classic 1980s machines have also appeared on the internet.

What’s the difference? Zork is not a PDP-10 executable, it’s actually a virtual machine executable, which is in turn run by an interpreter written for the PDP-10. For example, Java compiles to Java bytecode, which runs on the Java virtual machine (but not directly on any CPU). In the same way, Zork was compiled to “Z-machine” program files, called ZIP (which was of course used in 1990 by the much more well known PKZIP). To date, the compiler, “Zilch” has not been released, but the language specification and ZIP specifications have, which has led some people to write custom ZIP compilers, though with a different input language.

For more on the VM, check out Maya’s Zork retrospective. (And dig the featured art. Subtle!)

Of course, that’s not the only type of interpreter. Some programming languages are interpreted directly from source, like this BASIC hidden in the ESP32’s ROM.

Tiny11 Makes Windows 11 Small

If you often spin up a virtual machine just to run Windows, you might be sad that you have to allocate so much space for it. The Tiny11 project provides a Windows 11 installer that strips and compresses a bare minimum system do under 8GB of space. We aren’t sure what the licensing aspects of it all mean, but there are a few things you need to know. You can see a video about the project below.

The installer requires you to activate Windows, so that’s probably a good thing from a legal standpoint. Besides being compressed, the installer, based on Window 11 Pro 22H2, removes sponsored applications and Teams. It does, however, have the component installer and the Microsoft store, so you can add back things you want that aren’t in the default install.

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Tiny RISC Virtual Machine Is Built For Speed

Most of us are familiar with virtual machines (VMs) as a way to test out various operating systems, reliably deploy servers and other software, or protect against potentially malicious software. But virtual machines aren’t limited to running full server or desktop operating systems. This tiny VM is capable of deploying software on less powerful systems like the Raspberry Pi or AVR microcontrollers, and it is exceptionally fast as well.

The virtual machine is built from scratch, including the RISC processor with only 61 opcodes, a 64 bit core, and runs code written in his own programming language called “Brackets” or in assembly. It’s designed to be modular, so only those things needed for a given application are loaded into the VM. With these design criteria it turns out to be up to seven times as fast as comparably small VMs like NanoVM. The project’s creator, [koder77], has even used its direct mouse readout and joystick functionality to control a Raspberry Pi 3D camera robot.

For anyone looking to add an efficient VM to a small computing environment, [koder77] has made the project open-source on his GitHub page. This also includes all of the modules he has created so far which greatly expand the project’s capabilities. For some further reading on exceedingly tiny virtual machines, we featured this project way back in 2012 which allows users to run Java on similar hardware.

Hard(er) Drives: Impractical, Slow, Amazing, And Incredible

Computer memory is a problem that has been solved for many years. But early on, it was more than just a small problem. We’ve many of the different kinds at Hackaday over the years, and we’ll link to some of them later on. But one of the original types of memory was called Delay Line memory, which worked by waiting for a signal to propagate slow enough through a device that it was essentially stored in the device. This was highly inefficient, but still a neat concept- one that [Tom7] has taken to entirely new levels of amazing and impractical as seen in the video below the break.

Such factors as “harm to society” are artfully considered

Starting with a demonstration of orbiting chainsaws, he then moves on to explaining how radio propagation waves could be used to temporarily store data while it’s in transit. He missed the opportunity to call it cloud storage, but we’ll forgive him. Extrapolating that further, he decided to use the Entire Internet to store data without its permission, utilizing large ICMP packets and even making it available as block storage in Linux.

Not content to use the entire Internet to store a few kb of data, he moved on to several thousand virtualized NES game systems which are all playing “an inventory management survival horror game” commonly known as Tetris. [Tom7] deconstructs Tetris, analyzing its Random Number Generator, gaming the system to store data in virtual NES consoles by the thousands. What data did he store? The source code to Tetris for the NES. And what did he do with it? Well, he mounted it and ran the program, of course!

The last Harder Drive we’ll leave for those who want to watch the video, because it’s a bit on the “ewww gross!” side of things but is also a bit less successful due to some magic smoke being released.

If none of these things we’ve mentioned were enough, then watch the video for an excellent breakdown of the cost, efficiency, and even the harm to society. For fun, he also tosses blockchain into the mix to see how it fares against the Harder Drives. There’s also at least one easter egg in the video, and the whimsical discussion of engineering is both entertaining and inspiring. How would you implement a Harder Drive?

[Tom7] also gives you the opportunity to follow along with the fun and mayhem by making much of the code available for your perusal. For more fun reading, check out this walk down computer memory lane that we covered last year, as well as a look into Acoustic Delay Line memory.

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Soundbar Bested By Virtual Android Bluetooth Sniffer

Out of the box, the Yamaha YAS-207 soundbar can be remotely controlled over Bluetooth, but only when using a dedicated application on iOS or Android. Users who want to command their hardware with their computer, or any other Bluetooth device for that matter, are left out in the cold. Or at least they were, before [Wejn] got on the case.

To capture the communication between the soundbar and the application, [Wejn] first installed Android-x86 in a virtual machine on his computer and then enabled the “Bluetooth HCI snoop log” within Developer Settings. From there, a netcat command running on the virtual Android device continually sent the contents of the btsnoop_hci.log file out to Wireshark on his Linux desktop. As he hit buttons in the Yamaha application, he could watch the data come in live. We’ve seen plenty of people use Android’s integrated Bluetooth packet capture in the past, but never quite like this. It’s certainly a tip worth mentally filing away for the future.

The Pi can now control the TOSLINK connected speakers.

From there, things move pretty quickly. [Wejn] is able to determine that the devices are communicating over a virtual serial port, and starts identifying individual command and response packets. It turns out the commands closely mirror the NEC IR codes that he’d previously decoded on a whim, which helped clear things up. Once the checksum was sorted out, writing some code that can talk to the soundbar from his Raspberry Pi media player was the next logical step.

[Wejn] combined this with the Shairport Sync project, which lets the Raspberry Pi turn on the speaker and switch the input over when he wants to stream AirPlay from his phone. But of course, the same technique could be applied to whatever source of digital audio captures your fancy.

This is one of those posts you should really read in its entirety to truly appreciate. While every device is going to be different, the basic principles and workflow that [Wejn] demonstrates in this project will absolutely be useful in your own reverse engineering adventures. If you’re more of a visual learner, we recently covered a series of YouTube tutorials that cover sniffing BLE devices that’s not to be missed as well.

Reverse Engineering An RGB Keyboard Under Linux

Hardware support under Linux is far better than it ever has been in the past. These days, most things “just work” out of the box, and you probably won’t have to compile any custom kernel modules. Certainly a far cry from where things were a decade ago. But that doesn’t mean everything will work to 100% of its abilities. Take for example, the Duck keyboard that [Cynthia Revström] has. Sure it works as a basic keyboard under any OS, but getting those fancy RGB LEDs working is another story entirely.

Don’t get the wrong idea here, [Cynthia] isn’t just trying to get the keyboard to flash along to music; the goal was to use the RGB lighting of the Ducky keyboard for notifications that the user can’t possibly ignore. Even the most laser-focused among us would have a hard time not noticing that the entire keyboard is blinking red. But the “DuckyRGB” software that you need to do something like that is Windows-only and apparently distributed via a sketchy Google Drive link. Yikes.

The first step to creating an alternative was to spin up a Windows VM and install DuckyRGB. From there, Wireshark could listen in between the virtual computer and the Ducky keyboard to see what the software was sending over the wire. After identifying a version number being sent in the clear, [Cynthia] was able to isolate the LED commands by searching for the hex color codes. From there, it was a relatively simple matter of writing some glue code to connect it up to an alert service and get notifications going.

There was only one problem; the keyboard didn’t work anymore. Turns out the tool that [Cynthia] wrote to control the keyboard’s LEDs was claiming the device so the kernel couldn’t access it for normal input. It took a detour with HIDAPI to get everyone playing together nicely, and now changing the color of your Ducky keyboard on Linux doesn’t turn it into a paperweight.

Even if you don’t have a Ducky keyboard, or aren’t particularly interested in having its LEDs blinked at you if you do, this project is a phenomenal example of practical USB reverse engineering. [Cynthia] says the inspiration for this project came from friend [Ben Cox], who’s write-up on creating USB userspace drivers we covered last year. If you’ve got and old USB gadget with Windows-only drivers, maybe it’s time you take a crack at unlocking it.

BeOS: The Alternate Universe’s Mac OS X

You’re likely familiar with the old tale about how Steve Jobs was ousted from Apple and started his own company, NeXT. Apple then bought NeXT and their technologies and brought Jobs back as CEO once again. However, Jobs’ path wasn’t unique, and the history of computing since then could’ve gone a whole lot different.

In 1990, Jean-Louis Gassée, who replaced Jobs in Apple as the head of Macintosh development, was also fired from the company. He then also formed his own computer company with the help of another ex-Apple employee, Steve Sakoman. They called it Be Inc, and their goal was to create a more modern operating system from scratch based on the object-oriented design of C++, using proprietary hardware that could allow for greater media capabilities unseen in personal computers at the time.

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