Questions about Kromi One
What it is, when you can get it, and what you can build for it. Missing something? Write to hello@kromi.one.
Kromi One
What is Kromi One?
A new home computer for 2D and 2.5D games and creative work, with its own chipset (Aura), firmware (KROM) and operating system (KromiOS). The home page explains the idea; this page answers what it doesn’t.
Why should I buy Kromi One?
Because computers have become hard to love. They are complicated and closed, updates break what worked yesterday, there are more Linux distributions than anyone can count, and you wait every time you switch one on. Kromi One is the opposite. It starts in seconds, loads programs fast, uses little power and is small enough to understand completely. Its operating system, KromiOS, is lightweight, and you can customize and extend it with your own Lua tools. It takes you back to the roots of home computing, without taking you back in time.
Does it run Amiga, C64 or other classic software?
No. Kromi One is a new platform, not a re-creation of an old one, and running other machines’ software is a deliberate non-goal. What it takes from the Amiga is the idea: one fixed, documented machine you can understand completely and program directly.
How is it different from MiSTer, MEGA65 or the Commander X16?
MiSTer recreates classic consoles and computers in an FPGA. MEGA65, the Commander X16 and the ZX Spectrum Next are new machines built around a classic platform. Kromi One has no legacy to be compatible with: it pairs a modern ARM processor with a new chipset designed for Full HD at 60 frames per second, and documents all of it. The full comparison is in Remake or new machine?
Why not just use a Raspberry Pi or a PC?
A Raspberry Pi runs old systems in software on top of Linux; a PC brings drivers, updates and layers of software between you and the hardware. Kromi One is one machine with its own chipset that starts in seconds and that you can learn completely, from the firmware to the last pixel.
Why the AMD Kria and not a Raspberry Pi with an FPGA, or a custom chip?
The Kria K26 module combines four ARM cores and a large programmable chip in one package, with fast memory shared between them, DisplayPort output and low power use. A Raspberry Pi connected to a separate FPGA was considered, but its link is too slow for a chipset that draws Full HD at 60 frames per second. A dedicated chip makes sense only later; for now, programmable logic lets Aura keep improving after machines have shipped.
Buying
When can I buy Kromi One?
There is no date yet. The developer edition comes first: the prototype on the AMD Kria KV260 kit, for early supporters and backers. Kromi One, with its own board and case, follows. Join the mailing list to hear first.
What will it cost?
The price isn’t decided yet. We’ll publish it once it is.
Where will the crowdfunding run, and which countries will it ship to?
Neither is decided yet. The mailing list hears first.
What is the developer edition?
The first Kromi One: a prototype built on the AMD Kria KV260 kit, with the same Aura chipset and KROM firmware. It is reserved for the people who support the project early, and for backers if we run a crowdfunding campaign. Kromi One with its own board and case comes after it. Join the mailing list to hear when reservations open.
What will Kromi One look like?
Good question, and we’d like to answer it with one of our own: would you prefer a compact mini computer, or a full machine with a built-in keyboard in the style of the Atari ST or the Amiga 500? Write your ideas to hello@kromi.one. We’d love to hear from you.
The machine
What’s inside?
An AMD Kria K26 module: four ARM Cortex-A53 cores at 1.33 GHz, 4 GB of DDR4 memory and the programmable logic that runs Aura. Plus 16 GB of internal storage, a full-size SD card slot, DisplayPort for a Full HD picture at 60 Hz, USB and Gigabit Ethernet. The whole machine is designed to draw less than 60 W.
What can the graphics do beyond the numbers on the home page?
Aura composes a background and four layers on every frame, each with its own position, wrap-around scrolling, transparency and blend mode (normal, add, multiply, screen). Sprites can be rotated, scaled and tinted. A scaler enlarges a smaller picture up to four times with sharp pixels, smooth filtering or AMD FSR 1, so a game can draw pixel art at 640 × 360 or 480 × 270, or a detailed scene at 720p, while text and HUD layers stay sharp at 1080p. Colour grading uses the same 3D lookup tables film tools use. Tile maps and raster effects, as the Amiga’s Copper did them, are next.
What does 2.5D mean? Will there be 3D?
2.5D means textured triangles: meshes with texture and perspective, for deforming and animating characters, and for perspective or isometric scenes. It is not a full 3D pipeline, and Kromi One isn’t aiming at modern 3D games. Since October 2026 the chipset draws them itself: 20,160 textured triangles per frame at 60 Hz, including eight characters with 16 bones each.
What can the sound do?
Kromi One has its own sound chip, Aria, part of the Aura chipset. It plays 48 kHz stereo with low latency and is designed to send it to the audio output and over DisplayPort to the monitor. Today programs mix music and effects in software on the processor cores. A sound engine is planned on one of the module’s real-time cores: many voices, each with its own pitch, volume, panning, envelope and filter; effects such as reverb and echo; wavetable and FM synthesis and tracker music. Programs send it sounds and commands, so the main cores stay free for the game.
Which keyboards, mice and controllers will work?
USB keyboards, mice and game controllers: Kromi One supports the standard USB input devices, with hot-plugging. Programs get the raw input with no acceleration, as games want it.
How do chipset improvements reach machines already sold?
Through updates of KROM and the Aura chipset together, as one tested unit. The update system is designed but not built yet: an update goes into a second slot, and the machine switches over only after it has started successfully several times; otherwise it goes back to the previous version on its own. A recovery button will restore a working system from an SD card or USB stick.
Developing for Kromi One
Can programs access the chipset’s registers directly?
No, and on purpose. Programs give Aura lists of drawing commands through KROM, which checks every command, at about one microsecond each. Games that wrote to the Amiga’s hardware directly broke when the next chipset came; with KROM in between, software keeps running when Aura improves.
Do games run under KromiOS or on their own?
Either. A game can run inside KromiOS or take over the whole machine without it; KROM always stays underneath. SD cards hold programs and data like disks, but nothing on a card runs by itself: you start it.
Which languages and tools can I use?
C17, freestanding C++20 and AArch64 assembly, with GCC or LLVM/Clang and CMake. Programs are linked statically and packed into a single file. KromiOS itself can be extended with Lua scripts.
Can I port an existing game engine?
Kromi One has no Linux, no POSIX and no standard C library underneath, so engines built for those don’t run as they are. The SDK is deliberately small: the KROM interface, the chipset commands and tools, not an engine. Small engines written in C or C++ can be ported to it. Large engines like Unity or Godot can’t run on Kromi One as they are. Whether there will be plugins to build for Kromi One from them isn’t decided yet, but we’re keeping it close in view.
Is there an emulator, and how do I debug?
Yes: an emulator based on QEMU, with a model of Aura that draws exactly the same frames as the reference renderer (it doesn’t imitate timing). You debug with GDB. It isn’t public yet; it will come with the developer edition.
Can I release software without the store?
Yes, you can share or sell your programs anywhere: on SD cards, on your own website or through the optional KromiOS store. Kromi One runs unsigned programs, and no store, account or approval is needed to run them. Programs can carry an optional signature so people can see who made them.
Will my software keep running on future versions?
Yes. Programs only use KROM’s documented interface, never the hardware directly. New versions only add to that interface and never change what exists, and every release is tested against programs built for older ones. Once the interface is frozen for the first release, programs built for it keep running for the whole life of Kromi One.
Is Kromi One open source?
Not for now. KROM is closed during development. The documentation of the machine will be public, and the terms for the SDK, the examples and the chipset aren’t decided yet.
Is there a community, and how can I help?
Not yet. A place for developers and players opens with the developer edition. Until then, you can follow the build on Hackster, where questions are welcome in the comments. The mailing list hears first, and if you’d like to build something for Kromi One, write to hello@kromi.one.
Using it
Does KromiOS need an account or an internet connection?
No. Every built-in application and every system function works without a network or an account, and nothing is uploaded automatically.
How fast does it start?
In seconds. The goal is an interactive desktop about five seconds after KROM hands over.
Does Kromi One have a web browser?
Not in the first release. Kromi One is a computer for creating and playing, not for scrolling. A web browser is on the roadmap for later.
What does the KromiOS store charge?
Much less than Steam or Playdate. The fee model and the numbers aren’t decided yet.