Huge home-built computer used for Tetris
bbc.co.uk
bbc.co.uk
This is about the "Megaprocessor" - a CPU built entirely from discrete components. It's an amazing project, superbly executed, and submitted/discussed here on HN many times.
You can see some of the previous submissions by using this search:
https://hn.algolia.com/?query=megaprocessor&sort=byDate&date...
Recent submissions haven't had much discussion, but it deserves it. The testing and verification processes alone are fascinating - just how do you test something like this?
Amazing project.
I am impressed by this computer because it is verbose and thus educational.
Building a complete computer the size of a room isn't easy at all, because the connections between the elements have to be active transmission lines, and Vcc and GND still have to be clean enough to avoid spurious switching.
There's a whole order of magnitude of extra design pain involved in building something that big, including LEDS in all the elements, and making it run fast enough not to be completely useless.
While on that topic; i will read the docs and watch the videos for educational purposes. ;)
As it happens I know Zoe (who wrote this) very well and would be happy to pass on constructive suggestions on what folks would like to see in this article (and other tech. articles from the BBC).
> Huge home-built computer used for Tetris
This makes it seem like the guy just wanted to play Tetris and took an extremely roundabout way to do it, where in fact he built the thing specifically to show the insane complexity we all carry around in our pockets and take for granted (I include myself in that statement 100%). Modern computers are nothing short of an engineering marvel and something like this, which is only a millionth as powerful and not capable of nearly as much built from scratch takes up an entire room.
It reminds me a lot of that photo from not terribly long ago showing an Air Force crew unloading a 50 MB hard drive that was roughly the size of a walk in freezer.
A good comparison would be someone who built their own aircraft to demonstrate how insanely complex an aircraft is, and then the news story about it says "Local Man Builds own Plane to jump down to Florida for a Burger."
"You may have heard that computer processors consist of billions of transistors crunching through 0's and 1's. But what is actually happening inside these processors?
A man has recently build a computer out of individual transistors, the components that control electric currents to perform computations. Instead of using one chip with billions of transistors, he has used individual transistors wired together, allowing him to visualize the individual computing structures and the electric currents that flow through them.
His completed computer has "only" 40,000 transistors, which is just enough to play a game of Tetris, but he hopes that the relative simplicity of this computer, as compared to a modern smartphone, can help educate the public on how computers actually work."
"You may have heard that computer processors consist of billions of transistors crunching through 0's and 1's. You've never seen them, but with this room-sized processor, you can."
Spoiler alert: his Tetris skills are inversely proportional to his computer building skills.
It really is amazing to see the thing up close. Especially when you look at the sheer number of transistors that had to be soldered to make this.
My favourite part was when James said that he's started off by just wanting a better understanding of how logic gates worked, and it just escalated from there.
That's hilarious. Maybe a common thing. My posts on analog computing, esp neural or general-purpose, started similarly. I noticed analog and digital cell development used similar tools. Also that they used to build computers that way. The rabbit hole followed.
The Megaprocessor uses through hole components. Something similar using surface mount components could be substantially cheaper, mostly because it could be smaller. This means it will need less of all the expensive supporting parts. The components themselves are only a small part of the cost.
"How big would a modern CPU be at this scale? The Apple A8X, found in the iPad Air 2, contains about 3 billion transistors. (This is comparable to the number of transistors in modern desktop computer CPUs as well.) At the scale of the MOnSter 6502, that would take about 885,000 square feet (82000 square meters) — an area about 940 ft (286 m) square."
Follows the same logic, but much cheaper.
And you still get blinkenlights per gate or transistor in emulated design.
A good programming analogy is people confusing the purpose of a programming Koan collection and helpfully suggesting the participant should google the answers. Or even worse than programming Koans, ditto but for meditation Koans. The point of the experience is to do it your way, by yourself...
Personally I'd like to play with RTL gate logic using modern transistors "in my infinite spare time". There's a certain alternative history component aspect. Imagine if instead of leaky, low beta, low Ft, low breakdown voltage germanium transistors, RTL was implemented with top of the line 2010s discretes. Yeah yeah I know RTL begat DTL begat TTL using contemporary technology, but in alternate history world, how would life have changed?
Perhaps the generally shitty weather tends to keep them tinkering away in their basements!