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Uxn Sticker
Uxn Sticker15C06

Uxn is the virtual machine powering the Hundred Rabbits software.

This one-page computer, programmable in Uxntal, is an portability layer with a focus on hosting graphical tools and games. It lives at the heart of the Varvara ecosystem.

This wiki along with most of the audio-visual projects documented on it are running on Uxn.

Memory

Uxn utilizes two circular stacks of bytes, the return stack allows it to tunnel through 128 subroutines and find its way back, and 64kb of addressable working memory. It can interface with up to 16 peripherals, such as screens and controllers. Uxn has no undefined behaviors, and cannot error.

SharedMemoryRAMData64kb pages
PrivateStacksWorking StackData256 bytes
Pointer1 byte
Return StackData256 bytes
Pointer1 byte
IODevicesData256 bytes

Basic Emulator

Here is an implementation of a basic Uxn emulator in 150 lines of C which includes the Console device and passes the opcode tests.

cc uxnmin.c -o uxnmin view raw

Basic Assembler

Here is a self-hosted implementation of the assembler in 400 lines of Uxntal, capable of assembling itself.

cat uxnasm.tal | uxncli uxnasm.bin > uxnasm-bootstrap.rom view raw

Here is the 1.4kb binary data of the assembler above, alternatively, a new one can be created with uxnasm.c.

xxd -r -p uxnasm.rom uxnasm.tal view raw

Stack-machines programming make for an habitable bedrock abstraction for this scale of personal computing as one can comfortably write programs in assembly to tackle most computation projects with what feels like high-level abstractions.

Original illustrations created
by Rekka Bellum.


Rostiger's Uxn Zine
Rostiger's Uxn Zine16X08
The Sound Of Plumpkins
varvara — The Sound Of Plumpkins16C06

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