V1 alpha — running on the bench since August 2026

A little console you can open

It plays like an arcade machine and opens like a text editor. Every game is a Lua script you can read, change and rewrite — including the ones somebody else wrote.

▶ Play one right here See the board Read the specification

A shoot'em up running on papyDeck: a ship over a starfield, enemies, a scrolling nebula — shmup, running on the board

Change a number, press Run

A whole game: a level, a character who walks and jumps, and collisions. The three constants at the top are the ones worth breaking first — set JUMP to -8 and he clears anything; make GRAVITY phy.PX // 8 and he floats down like a feather.

Notice what the program does not do. It never draws the scenery: the level is a tile background, which the mixer chip scrolls for free, so the whole frame costs one sprite — the hero. That is the budget this console is built around, and it is why _draw is two lines long.

It runs in this page, on the same C core as the board — no account, nothing sent anywhere. A mistake gives you an error with its line number, never a dead console.

Arrows to walk, Space to jump.

The platformer running: a character on a grassy ledge under a blue sky

-- A platformer, whole. Change a number and press Run.

gfx.bundle()                 -- the game's art, from its folder
local level = require("tuto02")
level.charger()              -- tiled background + collision map

-- Gravity in pixels per frame, squared. Integers only, hence //.
local GRAVITY = phy.PX // 4  -- try // 8: he floats
local WALK    = 2 * phy.PX   -- pixels per frame
local JUMP    = -5 * phy.PX  -- try -8: he clears anything

phy.gravity(0, GRAVITY)

local start = level.objets[1]   -- the level says where he starts
local hero = level.creer("heros", start.x, start.y)
phy.flags(hero, phy.MASK | phy.GRAVITY)  -- hits walls, falls

local state, left, prev = "repos", false, 0

function _update()
  local p = pad.get()
  local pressed = p & ~prev
  prev = p

-- phy.vel writes BOTH components: read vy back first, or
  -- gravity is cancelled every frame and the hero hangs.
  local _, vy = phy.vel(hero)
  local vx = 0
  if p & pad.LEFT  ~= 0 then vx, left = -WALK, true  end
  if p & pad.RIGHT ~= 0 then vx, left =  WALK, false end

-- Coyote time is in the engine: still "on the ground" for a few
  -- frames after a ledge, or every jump off an edge would fail.
  local _, grounded = phy.ground(hero)
  if pressed & pad.A ~= 0 and grounded then vy = JUMP end

phy.vel(hero, vx, vy)
  phy.step()                 -- gravity, collisions, animation

if phy.touch(hero) & phy.UP ~= 0 then    -- head on the ceiling
    local nvx = phy.vel(hero)
    phy.vel(hero, nvx, 0)
  end

-- On the ground you walk or rest; in the air you rise or fall.
  local _, g = phy.ground(hero)
  local _, v = phy.vel(hero)
  local want = (g and (vx ~= 0 and "marche" or "repos"))
            or (v < 0 and "saut" or "chute")
  if want ~= state then
    state = want
    phy.anim(hero, level.anims.heros[state])
  end
end

function _draw()
  local img, x, y = phy.sprite(hero)
  gfx.sprite(img, x, y, left and gfx.FLIP_H or 0)
end

Want to go further?

The demo above is one game, in one file. The full simulator holds the games people have published, and a set of tutorials that build a game one feature at a time — tiles, layers, scenery, objects, sound.

Anything published can be cloned: you get your own copy, its art and its levels included, and you change whatever you want. Playing and reading the source need nothing at all. Keeping your copy, and publishing a game of your own, is what an account is for.

Open the simulator ↗

Write your own

Lua on the console itself, a sandboxed VM, and errors that print a line number instead of taking the machine down. No toolchain, no cross-compiler, no cable: write it, copy the folder to the card, play.

Play what others wrote

Games are plain folders. The console lists the published games, fetches one over Wi-Fi onto its card, and you can open the source right after — and see exactly how the trick was done.

Open by licence, public soon

Hardware under CERN-OHL-P, firmware under MIT: the licences are chosen and their notices are already in the tree. The repositories are private while the V1 board lands — when they open, the schematic, the board and every line of firmware are yours to read, fork and manufacture.

See it run

Two games, each recorded twice: in the browser simulator, then on the board itself over HDMI. Same Lua, same art, same engine — that is the whole point of the simulator, and the only honest way to show it is side by side. Sound is on.

The machine

Sixty millimetres square, and the reason the games above hold 60 frames per second without tearing. This is the part for people who want to know how.

640×480at 60 Hz over HDMI
3 000sprite pixels per scanline
6Cortex-M33 cores
60 mmsquare board

The papyDeck board, 60 by 60 millimetres

Why three chips

A scanline lasts 31.75 µs — 8 000 cycles of one core at 252 MHz. Blitting 3 000 sprite pixels costs 6 000 of them, before the background is fetched, composited and pushed out. So sprites get a chip whose two cores work alternate lines, background and mixing get a second, and the game gets the third. Each one brings its own SRAM and its own NOR, which is the bandwidth that actually binds.

Real arcade guts

Three RP2350B sharing one oscillator, six cores, 3 000 opaque sprite-pixels per scanline measured on the board — roughly twice a Neo Geo — plus a scrolling tile background, over plain HDMI, with no tearing by construction.

Where the project stands

The V1 alpha board arrived on 26 August 2026 and has been on the bench since. Running today: HDMI out from the three chips, sprites and a scrolling tile background, games loaded from the micro-SD card, Bluetooth gamepads, Wi-Fi, published games downloaded straight onto the card from the console’s own menu, four-channel music and sampled effects out of the headphone jack, and the console updating its own four firmwares over the air. A browser simulator runs the same core as the board, with tutorials you can read and clone. Still open: HDMI audio, the verified leaderboard, and the V1 board itself — a voltage supervisor and a secure element are going on it.

Nothing here is for sale, and there is no release date. The pages below are the honest version: measured figures, decisions with their reasons, and the parts that are still open.