Virtual 8-bit computer with 256 bytes of memory. A powerful learning tool for mastering Assembler, with lessons available in English. Try your hand at low-level programming!
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Curator Review

Recommended
By Sho Po Razraby? October 23

“Ця штука допоможе вам стати крутим хакером і взломати бункер путіна. А ще це від україеського розробника”

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About This Software

ASTRA-256 — A BINARY VIRTUAL MACHINE PROGRAMMED IN ASSEMBLER

Step into the era of early computing and feel like a real engineer from the past. ASTRA-256 isn’t just a computer — it’s a complete educational environment where you write real Assembler code for a virtual von Neumann architecture machine.

LEARN BY PLAYING

ASTRA-256 is:

  • An interactive simulator for learning Assembler from scratch.

  • A logic puzzle for those who love “real” programming.

  • A nostalgic time machine for veterans of the LPG-30, Altair 8800, and PDP-11.

This is the kind of machine pioneers of computing once used to solve real problems — under tight resource constraints, just like in the 1970s.

WHY LEARN ASSEMBLER?

Assembler is the language the machine truly understands. It’s not obsolete — it’s foundational.

  • Still used in microcontrollers and embedded systems: from home appliances and automotive electronics to medical devices and IoT.

  • Gives you full control over the hardware — drivers, firmware, DSP, memory, and registers.

  • Essential for cybersecurity: reverse engineering, malware analysis, hacking, and low-level defense.

  • Helps you understand how high-level languages like Java, C++, and Python work under the hood.

  • Reveals the essence of computation — how bits become intelligence, how stacks, memory, and ALUs operate.

Understand Assembler, and you’ll understand how everything else works.

WHAT CAN ASTRA-256 DO?

  • 8-bit processor with accumulator and visible registers: IP, IN, OUT, SP, FLAGS.

  • 256 bytes of memory — just like the original Altair 8800 released in 1975 with the Intel 8080.

  • 75 instructions grouped by purpose: control flow, data movement, arithmetic, stack, I/O, and more.

  • Lessons and documentation in five languages — printable, just like in the good old days.

Start with simple programs and progress to complex algorithms: square roots, trigonometry, even mini-games.

ASTRA-256 runs on a custom Assembler designed specifically for this environment. We intentionally offer an extended instruction set — similar to what you’ll find in modern microcontrollers and processors.

It’s a hands-on way to gain foundational experience with low-level hardware logic — the kind that prepares you to work with any modern microcontroller. The principles haven’t changed.

PLAY, LEARN, PROGRAM

Everything you need is built in: editor, debugger, help system.

Everything is real: memory, registers, instructions.

Everything is here to help you understand how computers truly work — not at the interface level, but at the bit level.

Who knows — maybe you’ll be the one to write the program that sends Elon Musk to Mars.

System Requirements

Windows
SteamOS + Linux
    Minimum:
    • OS *: Windows 11, 10, 8.1, 8, 7, Vista (32, 64 bit)
    • Processor: Dual Core 2 GHz
    • Memory: 64 MB RAM
    • Graphics: Requires a Direct3D 11 compatible videocard
    • DirectX: Version 11
    • Storage: 50 MB available space
* Starting January 1st, 2024, the Steam Client will only support Windows 10 and later versions.
    Minimum:
    • OS: Ubuntu 16.04 LTS 64-Bit
    • Processor: Dual Core 2 GHz
    • Memory: 64 MB RAM
    • Graphics: Requires a OpenGL 1.4 compatible videocard
    • Storage: 50 MB available space

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Mostly Positive (18 reviews)






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