MAD-65

MAD-65

Monochrome Arcade Device

MAD-65 is a home-built arcade console. Two 65C02 processors run side by side at 14.3 MHz — one plays the game, the other draws it — on a black-and-white screen like it's 1982, except it's not.

It is a real machine made of real chips you can source today, but until you do, you can use our simulator which runs on your PC right now.

Play a game →

C.E.T.A.S. — the first MAD-65 game. Beta out now: download, unzip, run. No console required.

Build the console →

Three boards, ~33 chips, all through-hole. What it is, what it costs, and how far along the design is.

Write a game for it →

Full technical documentation, the OS API, and a developer's guide with worked examples in 6502 assembly.

What it does

With no game cartridge fitted, MAD-65 runs its built-in diagnostic demo. It exercises most of the hardware and firmware at once: sound chips, vector graphics, scrolling text, live response to the joysticks, and the build date of each ROM — printed into the static background layer, which proves the background-copy hardware is working too. When you see the cube spinning in space, your machine and both its ROMs are working correctly.

MAD-65 diagnostic demo: a wireframe cube rotating over a starfield, with both ROM build dates in the corner
The built-in diagnostic demo. 400×300 logical pixels, one bit deep, scaled to 800×600 at 60 Hz.
CPUs2× WDC W65C02S @ 14.318 MHz
Display400×300 mono, output as 800×600 SVGA @ 60 Hz
Sound2× SN76489 PSG + 1× YM2413 FM, stereo
Memory64 kB per CPU, 128 kB double-buffered VRAM
Cartridges8 kB banked window, up to 1 MB per cartridge
Logic74HC series TTL + 5× ATF1508AS CPLD. No FPGA, no SoC.

More about the hardware →

News

New firmware. Games get 8 kB more RAM: once a cartridge boots, the half of the CPU ROM that holds the demo is theirs to use. The demo's music is now stored compressed to make room. Build 260911.

New firmware. Compressed loading, and rectangles on the background layer — including the comb, which is the only way to get partial coverage onto a write-only surface. Build 260903.

New firmware. CIRCLE16 and a rotated/scaled polygon family, both GPU-clipped and off-screen safe. Build 260901.

New firmware. Full-resolution lines and polyline chains. Build 260827.

New firmware. Ghost sprites, and a new demo theme by Maro Szczerski. Build 260824.

C.E.T.A.S. beta is available. The first game for the console, playable today on Windows through the bundled simulator. Download it here.

First fully working firmware. Both ROMs with the built-in diagnostic demo completed.