Cray C90 Supercomputer Wristwatch: A Geek’s Dream Come True

In a remarkable blend of nostalgia and cutting-edge technology, an electrical engineer has brought the Cray C90 supercomputer to the modern era, but with a twist: it fits on your wrist. Chris Fenton, a supercomputing expert, has crafted a miniaturized version of the iconic Cray C90, creating a wristwatch that is as complex as it is captivating.

Using a combination of 3D printing, an OLED display, and an FPGA development board, Fenton’s creation not only pays homage to the legendary Cray Y-MP C916 but also challenges the norms of what a wristwatch can be. His design involved meticulous modeling to achieve a 1/25-scale replica of the supercomputer, complete with custom-fitted circuit boards and a mounted OLED display. The watch also includes a rechargeable battery and accommodates a NATO-style wrist strap, ensuring it remains functional as well as fascinating.

At the heart of this wearable marvel is a Diligent CMOD-A7 FPGA development board. This board runs a Cray CPU core at 105 MHz, mirroring the clock speed of the Cray J90. While this is slightly less than the C90’s original 244 MHz, it’s an impressive feat for a wristwatch. A Teensy 3.6 microcontroller handles the reset signals and SPI interface, and it also drives the OLED display, bringing the entire system together.

Fenton’s passion for computational simulations led him to write software in Python for his unique timepiece. His program performs n-body gravity simulations, demonstrating the gravitational interactions between Jupiter and 63 of its moons. The coordinates for these simulations are sourced from NASA’s Horizons system, ensuring accuracy. The result is a mesmerizing display of Jupiter’s moons orbiting the planet in real-time on the watch face.

While the watch’s primary function isn’t to tell time in a traditional sense, it offers a novel way to do so by interpreting the positions of Jupiter’s moons. This unconventional approach to timekeeping underscores Fenton’s statement that using the watch “should be as incomprehensible as my motivation for creating it in the first place.”

The Cray C90 wristwatch isn’t just a tribute to supercomputing history; it’s a programmable platform that invites further exploration and customization. Although its towering structure might pose practical challenges, such as navigating doorways without damage, the watch’s intricate design and capabilities make it a standout piece for tech enthusiasts.

Fenton’s creation pushes the boundaries of wearable technology, blending complexity with a dash of whimsy. For those fascinated by the intersection of history, technology, and creative innovation, the Cray C90 wristwatch is a must-see marvel.