SPU-13

SPU-13 is an open FPGA platform for deterministic exact arithmetic, reproducible inference, and hardware evidence.

Current direction

The active work is a GPU and streaming rasterizer — a graphics pipeline that generates pixels in step with the display beam and holds no framebuffer, so it uses no external memory bandwidth.

It reached physical silicon across three consecutive days in September 2026: first video output, then rasterized geometry, then a depth-resolved image with each pixel decided by interpolated depth. Each result was measured against a prediction registered before the hardware was programmed.

See Evidence for the numbers and photographs, and the graphics track for what it is not yet — no 3D, no shading, no host link.

The SOM sidecar was the prior product direction. It was paused on 3 September 2026 pending a retest, not abandoned; its results stand and remain published.

What is distinctive

• Exact integer and fractional arithmetic instead of rounded floating point in the supported paths — no floating point, no division and no transcendentals in the RTL.
• A software oracle that is normative for RTL correctness.
• Hardware claims tied to dated, hash-pinned evidence.
• Open hardware, software, and documentation under separate published licences.

SPU-13 remains a platform in development, not a finished commercial product. Experimental architecture work, future integration targets, and negative results are labelled in the repository rather than presented as completed capability.

Read the source

Open the SPU repository for the full brief, reproduction commands, current status, evidence ledger, and technical documentation.