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Comment by zeteo | Hacker News Reader

By some definition of "scratch", we've also built 8-bit computers from scratch in my Electronics class. My respect for this student's accomplishment is proportional to how much of the processor he has designed and built himself; opcode design and management is a highly nontrivial task. On the other hand, if he has built the processor from pre-existing schematics, the accomplishment simply shows a steady soldering hand and good mental endurance.

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I think you guys should look a little closer before writing him off.

He pumped the OS in one bit at a time using DIP switches, wrote his own hex editor, and then wrote his own assembler and emulator, in javascript/canvas: http://web.mac.com/teisenmann/iWeb/adeptpage/adept_compiler....

The OS code is here: http://web.mac.com/teisenmann/iWeb/adeptpage/DUO_OS.txt

Run it through the emulator, it works.

Definitely not just a bit of light soldering...

His enthusiasm and tenacity are admirable, but he still has a lot to learn (and the "this guy is smarter than anyone else" hype in the article is overblown). That's not an OS, it's a rudimentary shell and a couple of simple programs that can be called from it. To anyone who has ever taken an operating systems class (where you usually do have to write your own OS), it's quite obvious that he hasn't even begun to tackle the kind of problems that real OSs deal with.

No, the processor appears to be constructed from 74LSxxx TTL logic chips. The memory is 2x32KB off-the-shelf SRAM units, but there comes a point where building things out of quad J-K flip-flops just becomes an exercise in patience and unnecessary spending. The registers are FFs, why make all of the memory that way? Just to say you did it? It doesn't add to the learning experience, just the drudgery.

Yep... In the long run, I think you would get at least equal educational value by prototyping some parts of the computer in TTL logic, and then writing it in VHDL for an FPGA. Then, you could go into far more advanced things like pipelining, instruction caching and even multi-core design...

And it would be a lot faster (both in terms of building the thing, and in terms of how fast the processor would clock) and cheaper.

I think the GP comments wants to say that just soldering the TTL chips w.r.t somebody else's design is not that impressive. I too think so, I have not checked but if I found that the has designed the whole processor (custom op-codes and a whole new implementation of ALU) I would be much more impressed.

According to the website he "built and designed" the computer which I assume includes the instruction set, assembler, etc. I can't find any evidence to the contrary.

It's definitely cool -- not groundbreaking, because after all, people used to do this by hand :) It's a bit like rebuilding classic cars. Its fun to touch the hardware and imagine what Woz may have been thinking when he designed the Apple I 30+ years ago.

This is Jack Eisenmann's website for the Duo Adept, which includes further project details:

http://web.mac.com/teisenmann/iWeb/adeptpage/menu.html

It's not quite like rebuilding a classic car. It's more like a high schooler using the school workshop to fabricate car parts and building a car from his own blueprints. Sure, he may have purchased the speedometer and tires, but that doesn't really diminish the accomplishment.

Hopefully he will go on to work on a replacement for computer—car analogies.

Did you watch the video? This is inspiring to me on many levels.

This probably earned him a salaried job at essentially any place he wants to work. Or at the very least an internship.

I hope he considers skipping college. There's no reason for him to be driven into ~$50k worth of debt, and I've certainly been happy with my decision not to go.

I agree with you on everything except that he should skip college. This would land him a salaried job at a lot of places, but if he's truly interested in computer design he would probably want to work at IBM/Intel/AMD research departments and they certainly require a college education to just get through the interview filters.

Not to mention there is a lot of stuff he could learn at college that would actually be tremendously useful if he wants to continue in this path. Everything from the physics of conductors to more advanced electronics design are things that can be quite hard to pick up from tutorials online.

There are thousands, probably tens of thousands of people out there who have built a 8-bit computer (usually Z80 based), according to schematics, from a microprocessor, memory chips, and a bunch of TTL chips. (I know there were at least twenty at my old school, and it was a small college.) It's one college class out of more than thirty, and by no means a replacement for college as a whole.

It used to be the case that MIT required their CS undergraduate students build an 8-bit computer from TTL (mostly 74XX) chips on breadboard in their Freshman on Sophomore year. (And no, we didn't even get a Z80; the most complex parts we got was an ALU unit and a 8250 UART so you could communicate with the computer over an RS-232 port.) It's really too bad that this isn't something which is required any more.

Instead undergraduates are taught how to write Java programs, which is one of those languages where it's impossible to worry about silly things like cache-line misses, because there are too many layers of abstraction between you and the hardware.... (And yes, you youngsters should get off my lawn, while you're at it. :-)

What course number was that? Is it on OCW?

I'd also like to know if it's on OCW, would be very interesting.

Here you go!

http://ocw.mit.edu/courses/electrical-engineering-and-comput...

Do you mean 6.004[1]? I took that a few years ago and we virtually "built" a computer from scratch - laying down the wires with a hardware description language, writing a simple OS, etc. Unfortunately, it was all inside a simulator, so connecting the wires wasn't as tangible and satisfying as I would have liked. In the class, we heard that in the past students actually worked with physical components. Was still really fun and rewarding, though.

[1] http://6004.csail.mit.edu/

I'm guessing that he built this computer based on some DIY project, which means he followed directions. In college, the most important things you learn involve not following directions. Instead its about teaching you how to "think" and following directions doesn't involve "thinking" at the level that it is taught at college.

From my own experience, collage only teaches you to follow directions. You get punished if you actually think and use some other "direction" than that you've been told to follow.

Agreed, save the skipping college part. The debt incurred from college was paid off more than a decade ago. The gain from my education opened my mind and doors of opportunity. Even if you are smart, sometimes those doors will stay shut.

I'd like to know (for my own education), what were the benefits to you of going to college?

Making so much money that the debt wasn't really a big deal...and knowing that finding more jobs that pay the same (or more) isn't really a big deal...not hitting a glass ceiling every couple years because I wanted to enter positions that required a B.S. and then an M.S., etc. etc. etc.

My major was CS and math for undergrad:

(1) in-depth knowledge of math, which has always been an asset. Those that don't go to college have issues here.

(2) met like-minded friends that were inspiring and most are quite successful now.

(3) allowed me to go to grad-school and specialize in machine learning. This specialty opened doors that ultimately resulted in company ownership (yes it ended well)

(4) personal satisfaction in knowing that I can finish something with long term vision. College is only four years, but when you are young it seems daunting.

4 years is always a huge fraction of your life.

While I think the kid is awesome, I don't think it follows that skipping college is the best choice. If he's as brilliant as he seems, he ought to be able to get scholarships to some pretty good schools...where he can learn to go well beyond this, probably faster than he could on his own; even if it's just for the resources a good technical university (like MIT, Caltech, Stanford, etc.) provides.

He could be working with supercomputing, nanotech, quantum computing, Internet-scale problems, etc. in a couple of years at one of those schools. It would take much longer to get there on the DIY path. I know of what I speak: I went the path of most resistance and I was in my late 20s by the time I really started working with people I considered on or above my level and getting paid fairly for it...i.e. building things that millions of people use. I'm probably not as smart as this kid, admittedly, but I'm enough above average to know what his career path will most likely look like if he opts to skip university.

I'm not suggesting he won't be a monstrous success in the future. I'm pretty confident he will be. But, why not take the short cut?

It's the folks who aren't brilliant, that I think should skip college, or choose a super cheap school. Brilliant people should at least spend a few years in the environment of a great school so they can get a feel for how wide and accommodating the world is for a brilliant individual with drive and ambition.

This is an excellent and important point. If your ambitions lie along the lines of "supercomputing, nanotech, quantum computing, Internet-scale problems," etc, then skipping college is a terrible mistake, obviously.

It comes down to what he wants. Personally, I wanted freedom from debt, freedom from high school, and the freedom to work with creative people. Those factors made me decide to drop out of high school (after I had landed a game development internship, i.e. a solid job and therefore a solid resume for the future).

I think it's important to not seem like you're looking down on people who DO chose to go to college. Because surely you wouldn't like it if they looked down upon you?

Truth is you do get a lot more from college for your debt load than just job training.

(And just so you know, I went, but didn't finish, largely because I found myself making a very good living developing software and also because my personality has never accommodated being part of the student-underclass.)

College is a knife sharpener. If your knife was already sharp or you figured how to sharpen it on your own and how to convince other people of this fact, you don't need it.

Most people need it, because they can't do all this on their own. Furthermore, some of them have such good steel in their knife, that sharpening will be a great leap, and it would have been a waste, in some sense, to miss it. The tragedy is that we convinced everyone that they NEED the sharpening to have a good life, even if they have tin knives, as if a sharp knife is the only tool.

You make a good point. I looked at his website, and it does not seem he designed it himself. If he did I would expect to see some gate level or even block level diagrams of the actual processor. Designing a processor from scratch is pretty challenging, if you do it you would want to show your work.

He only has TTL chip diagrams which do not show the internal architecture.

It's still pretty impressive for a high school grad. Not to mention that he was able to code an OS and a few games.

Aren't most people that make computers high school graduates?

It says he just graduated high school. So I assume he isn't in college yet.

I suppose I should have worded my comment better.

AFAIK, the minimum definition for an OS usually contains either a file system or processes. I see no indication of that in this case.

Regardless of how much he actually did, this is quite an accomplishment in modern-day America. Even the most basic attempts at some task slightly related to engineering should be lauded. They are very rare these days.

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