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Articles about hardware design, simulation, and the tools we're building.

Pong in Hardware

A complete Pong game built from logic gates, registers, and memory — two paddles, a bouncing ball, and a 14-phase rendering pipeline, all without a CPU.

Game~80 nodes

Snake in Hardware

A complete Snake game built entirely from logic gates, registers, and memory — no CPU, no software, just digital circuits.

Game~100 nodes

Building a CPU from Scratch

From NAND gates to a working processor — fetch, decode, execute, all built from logic gates you can click.

CPU~300 nodes

How TPUs Do Calculations

Inside Google's Tensor Processing Units: a 2x2 systolic array built from logic gates. Watch matrix multiplication happen one clock cycle at a time.

Accelerator~60 nodes

Computing Trig in Hardware

How calculators and GPUs compute sine and cosine using only bit shifts and addition — the CORDIC algorithm, built from logic gates.

Accelerator~40 nodes

Sorting Networks

A fixed wiring of comparators that sorts any input in the same number of steps — no branches, no loops. The algorithm behind network switch fabrics, GPU sort, and median filters.

Accelerator~25 nodes

How Network Switches Work

Packet buffering, MAC address lookup, and forwarding — built from the same primitives as everything else.

Networking~50 nodes

Breakout in Hardware

A classic brick-breaking game built entirely from logic gates — ball physics, paddle control, brick collision detection, and score tracking, all without a CPU.

Game~90 nodes

AES in Hardware

Why Intel built AES into the CPU. SubBytes, XTime, and MixColumns — the operations behind the world's most deployed cipher, verified against FIPS 197.

Accelerator~60 nodes

ChaCha20 in Hardware

The TLS cipher that encrypts most of the internet, built from logic gates. Explore the ADD-XOR-ROTATE quarter-round with live interactive circuits.

Networking~50 nodes

CRC-32 in Hardware

The checksum at the end of every Ethernet frame and ZIP file — a 32-bit shift register with XOR feedback, running in the NIC on your machine right now.

Networking~15 nodes

A RISC-V CPU That Runs C

A 5-stage pipelined RISC-V processor with data forwarding and hazard detection — write C, compile it, and step through execution cycle by cycle.

CPU~200 nodes