In the realm of computer science and engineering, innovation often parallels feats of speed and efficiency. Most enthusiasts are well-acquainted with the term “speedrun,” typically associated with completing a video game in the shortest possible timeframe. However, a recent endeavor by Hackaday writer Julian Scheffers has introduced a novel concept—speedrunning the creation of a CPU. This experiment not only challenges our conventional views of processor design but also highlights the fascinating intersection of creativity and technical know-how.
In an impressive showcase of talent, Julian Scheffers undertook the ambitious project of creating a functional CPU from scratch utilizing Logisim, a logic simulator. Remarkably, this was accomplished in a mere six hours and named “Stovepipe,” a moniker chosen hastily rather than as a meaningful reference to its Victorian semblance. The project underscores Scheffers’ commitment to streamlined design, showing that even within the tight constraints of time, one can still produce a functional piece of technology.
Scheffers managed to complete the fundamental hardware components of Stovepipe in less than four hours. The remaining time was dedicated to formulating an assembler for the CPU. Central to the design was a minimalist instruction set architecture (ISA), crafted by methodically eliminating all non-essential features. The end result yielded eight significant opcodes packaged within a compact 512-bit space, a somewhat stark contrast to Scheffers’ previous creation, the GR8CPU, which featured a more complex 8192-bit architecture.
In its essence, Stovepipe exemplifies minimalist design in computing. The CPU incorporates a mere 256 bytes of RAM alongside an accumulator serving as the solitary user-accessible register. This simplicity means instructions take just one cycle to fetch, but their execution can range between one and three cycles depending on complexity. When juxtaposed with Scheffers’ earlier creation, Boa³², this new chip’s limitations are evident. Unlike its predecessor boasting 32 registers, Stovepipe demonstrates a more sluggish performance, although it does achieve quicker instruction loading times.
The comparison between Stovepipe and Boa³² illustrates an essential balancing act in CPU design: complexity versus efficiency. Binder, the more sophisticated Boa³², might resemble today’s high-end CPUs, such as the Ryzen 7 9800X3D, due to its pipelined architecture and distinctive address and data busses. The streamlined structure of Stovepipe, while showcasing ingenuity, signals a trade-off between operational speed and processing capabilities.
With the remarkable brevity in which Scheffers created Stovepipe—compared to the extensive two-month timeline for Boa³²—one ponders whether such rapid prototyping can yield a meaningful contribution to CPU development or if its practicality remains a mere curiosity.
Stovepipe cautions us against the allure of speed in technology creation. While it may not set records in terms of size versus performance, its very existence raises questions about the limits of processor design. The process of quickly assembling a CPU serves as a source of inspiration to aspiring engineers, igniting interest in hardware design often overshadowed by software leaps.
Despite the uncertain practical applications of such a minimalist CPU, the mere fact that something functional can emerge within just six hours is astounding. Scheffers hints at a potential Stovepipe 2, promising to time its creation with an actual speedrun stopwatch. This playful twist on CPU design signifies a call to arms for innovators—find freedom within constraints and achieve the seemingly impossible.
Ultimately, as the boundaries of technology continue to expand, knowing that impromptu achievements like Stovepipe can emerge even within limited time frames is a reassuring reminder of human ingenuity. Abandoning the notion of perfection allows for exploration and democratizes the process of invention, encouraging creative minds to redefine what is achievable in the fast-paced realm of computing.