June 28, 2026
Houston, we have chip drama
Examining circuit boards from the Space Shuttle's I/O Processor
People are losing it over the Space Shuttle’s chunky brain boards and weird old-school parts
TLDR: A close look at Space Shuttle computer boards shows how the orbiter ran on bulky, custom-built hardware that handled vital flight systems. In the comments, readers were split between amazement at the redundancy, curiosity about radiation toughness, and total chaos over the existence of glass capacitors.
The big reveal in this deep dive wasn’t just that NASA’s Space Shuttle computers were huge, heavy, and shockingly handmade by today’s standards — it’s that the community immediately turned the comments into a love letter to retro engineering. The article walks through the Shuttle’s input/output box, basically the machine that helped the main computer talk to engines, sensors, and astronaut screens. Instead of one neat modern chip, this thing was built from packed circuit boards, old magnetic memory, and even microcode stored by literally blowing tiny fuses. Yes, people are absolutely obsessed with that detail.
The strongest reactions were pure awe. One commenter jumped straight to: were these lower-density parts actually better at surviving radiation in space? Another revived the classic Shuttle fact that several computers ran the same instructions at once so one bad result could be outvoted — which, in comment-section terms, is basically “the spacecraft had built-in receipts.” There wasn’t much fighting, but there was a lot of delighted nerd drama over just how overbuilt and alien this hardware now feels. And then came the sleeper hit of the thread: glass capacitors. A commenter practically screamed in delight at discovering they existed, made by Corning no less. So while the article is about circuit boards, the comments tell the real story: people are mesmerized that humanity reached orbit with a flying brick of gold modules, fuse-programmed memory, and enough backup systems to make modern gadgets look emotionally fragile.
Key Points
- •Each Space Shuttle general-purpose computer consisted of a CPU and an I/O Processor, with the CPU being a 32-bit processor running at 420,000 instructions per second.
- •The I/O Processor was a separate programmable computer that handled the Shuttle computer’s input/output and supported 24 high-speed network connections.
- •The I/O Processor used an unusual architecture with 25 virtual processors and two different instruction sets on one physical processor, making it an early multithreaded design.
- •One examined circuit page was a network interface card supporting four 1-megabit-per-second network connections, while another page stored the IOP’s microcode in fuse-programmed chips.
- •The Shuttle used 28 data bus networks for performance and redundancy, and the MIA interface page converted noisy analog wire signals back into digital data values.