virtual machine

31 Articles

A blue screen is visible, with an ASCII image of the text "Hello World" is displayed.

Designing A CPU For Native BASIC

December 17, 2025 by 22 Comments

Over the years there have been a few CPUs designed to directly run a high-level programming language, the most common approach being to build a physical manifestation of a portable code virtual machine. An example might be the experimental Java processors which implemented the JVM. Similarly, in 1976 Itty Bitty Computers released an implementation of Tiny BASIC which used a simple virtual machine, and to celebrate 50 years of Tiny BASIC, [Zoltan Pekic] designed a CPU that mirrors that VM.

The CPU was created within a Digilent Anvyl board, and the VHDL file is freely available. The microcode mapping ROM was generated by a microcode compiler, also written by [Zoltan]. The original design could execute all of the 40 instructions included in the reference implementation of Tiny BASIC; later iterations extended it a bit more. To benchmark its performance, [Zoltan] set the clock rate on the development board equal to those of various other retrocomputers, then compared the times each took to calculate the prime numbers under 1000 using the same Tiny BASIC program. The BASIC CPU outperformed all of them except for Digital Microsystems’ HEX29. Continue reading “Designing A CPU For Native BASIC” →

C Project Turns Into Full-Fledged OS

October 14, 2025 by 7 Comments

While some of us may have learned C in order to interact with embedded electronics or deep with computing hardware of some sort, others learn C for the challenge alone. Compared to newer languages like Python there’s a lot that C leaves up to the programmer that can be incredibly daunting. At the beginning of the year [Ethan] set out with a goal of learning C for its own sake and ended up with a working operating system from scratch programmed in not only C but Assembly as well.

[Ethan] calls his project Moderate Overdose of System Eccentricity, or MooseOS. Original programming and testing was done in QEMU on a Mac where he was able to build all of the core components of the operating system one-by-one including a kernel, a basic filesystem, and drivers for PS/2 peripherals as well as 320×200 VGA video. It also includes a dock-based GUI with design cues from operating systems like Macintosh System 1. From that GUI users can launch a few applications, from a text editor, a file explorer, or a terminal. There’s plenty of additional information about this OS on his GitHub page as well as a separate blog post.

The project didn’t stay confined to the QEMU virtual machine either. A friend of his was throwing away a 2009-era desktop which [Ethan] quickly grabbed to test his operating system on bare metal. There was just one fault that the real hardware threw that QEMU never did, but with a bit of troubleshooting it was able to run. He also notes that this was inspired by a wiki called OSDev which, although a bit dated now, is a great place to go to learn about the fundamentals of operating systems. We’d also recommend checking out this project that performs a similar task but on the RISC-V instruction set instead.

Linux Fu: Windows Virtualization The Hard(ware) Way

August 21, 2025 by 31 Comments

As much as I love Linux, there are always one or two apps that I simply have to run under Windows for whatever reason. Sure, you can use wine, Crossover Office, or run Windows in a virtual machine, but it’s clunky, and I’m always fiddling with it to get it working right. But I recently came across something that — when used improperly — makes life pretty easy. Instead of virtualizing Windows or emulating it, I threw hardware at it, and it works surprisingly well.

Once Upon a Time

First, a story. Someone gave me a Surface Laptop 2 that was apparently dead. It wouldn’t charge, and you can’t remove the keyboard without power. Actually, you can with a paper clip, and I suggested pulling it to see if the screen would charge by itself. They said they had already bought a new computer, so they didn’t care.

Unsurprisingly, once I popped the keyboard off, the computer charged and was fine. You just have to replace the keyboard or use another one. Or use it as a tablet, which it is set up for anyway. But I have plenty of laptops and computers of every description. What was I going to do with this nice but keyboardless computer? Continue reading “Linux Fu: Windows Virtualization The Hard(ware) Way” →

Network Infrastructure And Demon-Slaying: Virtualization Expands What A Desktop Can Do

June 11, 2025 by 21 Comments

The original DOOM is famously portable — any computer made within at least the last two decades, including those in printers, heart monitors, passenger vehicles, and routers is almost guaranteed to have a port of the iconic 1993 shooter. The more modern iterations in the series are a little trickier to port, though. Multi-core processors, discrete graphics cards, and gigabytes of memory are generally needed, and it’ll be a long time before something like an off-the-shelf router has all of these components.