The Ant64

It's not a PC — it's a proper computer.

A modern computer inspired by the golden age of hardware creativity.

Ant64 is a brand-new computer designed from the ground up for games, music, demos, and creative computing — inspired by classic systems like the Amiga, Atari, arcade boards, and early workstations, but built with modern silicon.

At its heart is FireStorm — a RISC-V CPU and custom chipset, both implemented in the same large FPGA. There are no separate "main CPU" and "graphics chip" — they share registers, memory, and timing. Around FireStorm sit several dedicated helpers, each doing what it does best: a supervisor computer (DeMon, a Raspberry Pi CM5 running AntOS on Linux), a music/control MCU (Pulse, an ESP32-P4), and an input-protection MCU (Sticky).

This is not an emulator box. This is a real machine with real hardware personality.

Core Philosophy

• Hardware-accelerated graphics and audio — in silicon, not software
• Deterministic, low-latency behaviour — no surprises, no variance
• Immediate, tactile interaction — the machine responds, not the OS
• No GPU drivers, no shader compilers, no OS overhead
• Built to last, repair, and recover

If the Amiga, Atari, and arcade engineers were designing a system today — this is what they'd build.

Architecture at a Glance

FireStorm — The Heart of Ant64

FireStorm is a custom 64-bit RISC-V CPU with a complete custom chipset alongside it — graphics, audio, blitter, copper, raycaster — all running inside the same GoWin GW5AST FPGA.

The CPU and chipset share the FPGA's memory ports, scratchpad BSRAM, and bus fabric. There is no copy-and-DMA dance between "main RAM" and "video RAM"; the CPU writes a sprite attribute and the next scanline reflects it. The CPU starts a blit and gets an interrupt or a register flag when the blitter is done. The CPU programs the copper to alter palette mid-scanline. The whole machine has one timing domain and the CPU is part of it.

CPU side

• RV64GC compatible — vanilla RISC-V code runs unchanged
• Wide mode — hot-path code can live in dedicated 36-bit SRAM with 64 GPRs, 64 FPRs, wider immediates, predicated execution
• Seven custom extensions: Xcrisp (memory primitives), Xstack (BSRAM hardware stacks), Xcond (predication), Xlate (per-register memory translators), Xctx (hardware contexts), Xmath (games/audio/DSP math), plus the wide-register-file Xwide
• B-tree primitives, BAM trigonometry, single-instruction quaternion math and other primitives that make FireStorm distinctive for games and audio

Chipset side

Audio

• Hardware-mixed 128+ voice audio engine
• Sample playback from DDR3 or flash
• Live FM, virtual-analog, granular, and physical-modelling synthesis
• Pitch-shifting without time-stretch
• Designed for tracker, synth, and game audio workflows

FireStorm is fast, predictable, and always under your control.

More about FireStorm »

Memory

• DDR3 — 2.25GB on the Ant64, 4.5GB on the Ant64C, 1.125GB on the Ant64S (user-upgradable to 4.5GB), used for OS, applications, framebuffers, samples, art library
• Wide-mode SRAM — up to 1M × 36-bit (~4.5MB) of fast SRAM for hot-path code on Ant64 / Ant64C
• On-chip BSRAM — ~765KB total on GW5AST-138, used for sprite line buffers, palette RAM, copper lists, scratchpad

DeMon — The Supervisor Brain

DeMon is a Raspberry Pi CM5 (quad-core ARM, gigabytes of RAM, VideoCore GPU, running Linux), paired with an ESP32-C5 for wireless connectivity. AntOS lives here — not in the FPGA — so OS state survives FPGA bitstream reloads:

• Boots the system: configures the FPGA, loads the FireStorm boot image
• Hosts AntOS: filesystem, network, scripting, debug server, UI — including AntBASIC, a built-in line-numbered BASIC so quick on the CM5 that it outruns 1980s hand-assembly
• Provides a display feed into the FPGA over HDMI — AntOS UI plus sprite and tilemap layer descriptions that FireStorm renders and composites at scanout
• Triple SID audio engine — three software SID chip emulators (MOS 6581/8580) panned L/C/R; nine SID voices of iconic C64 timbre for system sounds, FX, SID file playback, and as a third compositional voice palette independent of Pulse
• SAM speech synthesizer — retro formant text-to-speech engine (in the tradition of S.A.M., 1982); voice prompts, accessibility, system narration, optional musical / dialogue use via Pulse and FireStorm trigger paths
• Owns the keyboard and touchscreen
• Phreak wireless subsystem via ESP32-C5 (Wi-Fi 6, Bluetooth 5.3, Thread, Zigbee, ESP-NOW), plus optional LoRa and GPS — see Communications
• JTAG access to the FPGA bitstream and flash
• NFC reader for instant system switching
• Cartridge port for recovery, expansion, and personalities

Can reprogram everything — FireStorm bitstream, Pulse, Sticky, Clicky, ESP32-C5 firmware.

If anything goes wrong — Ant64 can heal itself.

More about DeMon »

Pulse — Music & Sequencer

Built around the ESP32-P4 (single 400 MHz HP RISC-V core + 40 MHz LP core, 32MB PSRAM, PIE extensions for AI/DSP), Pulse is the hands-on musical brain:

• MIDI — DIN IN / OUT / THRU (MIDI 1.0) + USB MIDI 2.0 (both host and device) + MPE
• Mouse support
• 8× RGB-illuminated jog dials with integrated push buttons
• Round TFT display for jog dial labels and per-knob state
• MIPI display feed to FireStorm — Pulse composes its own sequencer / mixer / sample-browser UI and its sprite and tilemap layer descriptions and streams them to the chipset, which renders them at scanout
• On-Pulse synthesis via the open-source AMY library — additive / FM / PCM / partials / filters / envelopes, accelerated by ESP32-P4 PIE extensions; audio streamed to FireStorm for mixing with the chipset's hardware voices
• 32MB PSRAM for sample libraries, AMY patch banks, sequencer state, software synth engines
• 4× 3.5mm trigger / CV inputs (Kick · Snare · Sync · Foot)
• Classic synth emulators in firmware (speech synthesis provided by SAM on DeMon, accessible to Pulse over the bidirectional SPI link)
• OPI register window into FireStorm for low-latency audio parameter control and small packets parallel to MIPI

DeMon (the CM5) feeds the FPGA over HDMI, Pulse (an ESP32-P4) over MIPI. DeMon's feed is the system / boot UI, Pulse's the music / performance UI — both composited by FireStorm alongside the main application display.

Perfect for music, games, and creative tools.

More about Pulse »

Sticky — Safe 5V I/O

Handles classic controllers safely — Atari/Commodore/Sinclair/Amstrad sticks, Sega 3- and 6-button pads, the Amiga CD32, paddles, mice and analogue controls — while electrically isolating the FPGA and the rest of the system. Each of its four DE-9 ports reconfigures in firmware.

Your vintage controllers are safe — and so is the system.

Heavy Compute — No Separate Accelerator Needed

Earlier designs bolted a Raspberry Pi Zero 2W onto the FPGA as an optional accelerator. That's gone — DeMon is now itself a quad-core Raspberry Pi CM5, so the application-class CPU is already at the centre of the system. Heavy work runs on DeMon directly:

• Heavy emulation cores (e.g. Amiga 68040, x86 host)
• Complex codec work (video transcode, software audio plugins)
• Linux-based services for community-built extensions
• Larger AI / DSP and ML inference (quad ARM + NEON + VideoCore GPU)

For latency-sensitive offload, FireStorm can hand kernels to the on-die A25 hard core or to the CM over the provisional Xaccel path, and personalities reach these services through the Accelerator compatibility layer. FireStorm still handles everything on its own — the offload paths are opt-in.

Personality Cartridges

Plug in a cartridge to:

• Load a new FPGA "chipset" personality
• Install a different OS
• Simulate a classic computer or console
• Provide game or ROM libraries
• Reconfigure the system at boot

One machine. Many personalities.

Display and Output

Main display (via FPGA chipset)

• Main HDMI — 4K@60 via Parade PS176 DP→HDMI bridge
• Retro VGA + 3.5mm audio — via AG6201 HDMI→VGA bridge, supports 240p superresolution for genuine 15 kHz CRTs
• Line-doubled / tripled rendering for pixel-perfect scaling
• Raster effects, split screens, and layer reveals
• Per-layer Z-buffer ignore for classic ordering tricks
• Two supervisor feeds composited as overlay layers — DeMon (AntOS UI, over HDMI) and Pulse (sequencer UI, over MIPI)

Auxiliary displays (always active, FPGA-independent)

• Keyboard touchscreen — capacitive TFT on the keyboard, driven by DeMon over MIPI DSI. Always visible, never blanks. Shows AntOS status, recovery prompts, soft keys, file browser, debug info — and remains the user's window into the system even when the FPGA is being reloaded (personality cartridge swap, bitstream update, recovery).
• Circular display on the case — small round TFT mounted on the far left of the case, just above the keyboard. Driven by Pulse over SPI. Shows jog-dial labels, per-knob state, sequencer status, or any UI Pulse chooses. Also always visible, independent of FPGA state.

From CRT-style visuals to modern flat panels — Ant64 does both, and the auxiliary displays mean the machine is always visibly responsive even when the main display compositor is mid-reload.

Built for Creators

Ideal for: games · demos · music · retro development · hardware-accelerated tools

• Immediate response
• No driver hell
• No GPU black boxes
• Everything is inspectable and controllable

You don't fight the machine. You collaborate with it.

Why Ant64 Is Different

Ant64 gives creators direct access to hardware again. No driver hell. No black boxes. Not an appliance.

More details »