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DIY CPU Demo'd Running Minix
DeviceGuru writes "Bill Buzbee offered the first public demonstration of the open-source Minix OS — a cousin of Linux — running on his homebrew minicomputer, the Magic-1, at the Vintage Computer Festival in Mountain View, Calif. The Magic-1 minicomputer is built with 74-series TTL ICs using wire-wrap construction, and implements a homebrew, 8086-like ISA. Rather than using a commercial microprocessor, Buzbee created his own microcoded CPU that runs at 4.09 MHz, and is in the same ballpark as an old 8086 in performance and capabilities. The CPU has a 22-bit physical address bus and an 8-bit data bus."
Does it run Linux... I mean minix.. I mean... Oh forget it!
Nyhetsankaret.com -- det bÃsta av Sveriges Nyhetssido
I wonder if he got his ideas from watching DIY TV.
:P
They teach you how to do ANYTHING
Linus copied Minix. Well known fact !!
Beowulf Cluster
I wirewrapped a computer together back when building your own hardware was about the only option, and it wasn't a fun experience. I can't imagine actually wanting to do it, but to each his own.
I'm quite impressed that he went to the trouble of the cutaway side panel and the illumination. With all those switches and lights on the front we truly are one step closer to Star Trek technology.
A thistle is a fat salad for an ass's mouth...
the open-source Minix OS [CC] -- a cousin of Linux
That must be the same sense in which Dick Cheney is "a cousin of" Barak Obama.
I would really want to do this! I'm sure that the thing doesn't have an ethernet device, but I wonder if a terminal server device would do? Then I'd run some sort of web services on it. :) That'd be some true geek value.
Did he use appropriate era memory, you know the ol' 1k chips, meaning 1024 by 1?
Core memory? Hey kids, instead of stringing popcorn this holiday, we are gonna do memory cores!
Cool none the less.
"Wirewrap? That's crazy talk. It's a senior design project to implement a CPU and such in an FPGA. Do the whole thing in a Xilinx Spartan 3A. Don't cheat and use a Virtex-4 with the PowerPC core!"
With most FPGAs any idiot, hell, even a simple Java programmer can cobble toegether a basic CPU without having to understand such fundamentals such as clocking requirements, wire delays, boolean optimization , and other fundamental skills.
I have seen the results of Java programmers trying to experiment with FPGAs. Instead of steaming mounds of code, I see steaming mounds of unnecessary gates.
Kudos to this fellow. Even designing his own boards. Using a Spartan 'Educational Kit' just doesn't cut it to become an EE nowadays if you ask me. Anyone can do that.
This is the ultimate nerd project... The only way it could be more of a do-it-yourself project would be building it with all analog parts. I'm very impressed. The guy appears to have been really meticulous. Everything appears to be pretty well documented... I've only gone through about 1/4 of the stuff he has available. It's a lot of material. I definitely wouldn't have the patience to do a project like this...
From the site about the homemade processor:
/. to a server that's only running at 4 MHz? Have you no mercy?" My response: Nope.)
Except when I'm working on it, Magic-1 is connected to the net. It serves web pages at http://www.magic-1.org
Not any more!
(I know, I know, some of you might be thinking..."How could you be so cruel as to post a link on
All that to get a fraction of the performance of, say, a $10 embedded CPU that can already run Linux. Nice.
Oh, you're not stuck, you're just unable to let go of the onion rings.
a bewolf cluster of those!
uh...wait..
As long as we are using the family analogy, wouldn't Minix be more like an uncle to Linux?
I cant help but notice that the Magic-1 looks a lot like the original Altair 8800, star of the Homebrew Computer Club in the 70's. At least this can have a console hooked up to it, from the look of it, the Altair originally had to have all the programming done via the switches on the front alone!
"I bless every day that I continue to live, for every day is pure profit."
I'm not going to link to it, because I don't want this hobby project to go up in flames, but if you follow the links to the website of the guy who built it, you would find that he's actually running a webserver on it.
The guy went and built his own cpu from scratch, then ported his own o/s to it.
Really, just don't get more hardcore than that....
I salute him!
This is my sig.
I find projects like this very comforting. Maybe I'm mildly paranoid, but every now and then I wonder what life would be like if society collapses. Most of the technology we enjoy today can only be produced via huge infrastructures made possible by large, advanced, stable societies. This project shows that fundamental computing technology can be reproduced with relative ease on a very small scale with limited resources. That's a great thing. Time to make some hard copies of this computer design!
Dan East
Better known as 318230.
you really wouldn't want to make him mad...
Bill Buz wha?
fs
I'm a rabbit startled by the headlights of life
according to his other site
way to burst his computer into flames...
...in this picture translate to "I WILL NEVER GET LAID" in binary.
The neutrality of this sig is disputed.
For some reason even I don't understand I'd really like one of these. Maybe I miss the DEC PDP-11 from my youth too much.
At college, I took a Digital Electronics course where the course project was to design and build your own microprocessor from scratch. From paper RTN descriptions to the full working prototype on a PLC. Our group started out with 6 people, 3 of whom dropped the class and the other two couldn't program their way out of a paper bag. I wrote the entire process in VHDL in under 2 months, the other two barely pulled of just the documentation (not that I envied them). I was pretty pissed at my professor since I used a design flaw in the PLC board to double the speed of one word instructions and he took of points for it even though it ran fine... What you get when the prof is more interested in procedure and forcing people to work in groups then the actual science.
We've secretely replaced the Enterprise's dilithium crystals with Folgers crystals. Lets see if they notice.
The reason the Magic-1 isn't in service as a webserver is that, at the moment, Bill's showing it off at the Vintage Computer Festival.
I can just picture Woz now saying "The force is strong in this one. "
If you're just gonna use an FPGA, why not just design a virtual PC purely in software.
This thing is cool. Most current 'seniors' would hold a wire-wrap gun wrong and injure themselves.
It's more educational to do it with MSI TTL and wire-wrap. You learn something about power distribution/filtering, race conditions, fan-in and fan-out, etc. All of the analog things that you need to know in the real world.
Mea navis aericumbens anguillis abundat
It has an open guest telnet and a webserver running (when he's not working).
It is, apparently, slashdotted right now just through people following the chain of links and finding it.
How much slashdotting does it take to take a 4 MHz machine to it's knees?
And more importantly, did it stay UP during the slashdotting, but just get as slow as Unreal on a 100 MHZ machine w/o 3D-hardware acceleration?
I've toyed with the idea of doing this for years now, but it always seemed like it'd consume most of my free time for months or possibly years. In fact, i even briefly considered using discrete transistors, but that thought dragged me back to "just buy the damn CPU off the shelf". The fact that this guy *actually did it* is really impressive.
He gets da mad nerd props!
This was on slashdot wayback.
It was running minix back then. And you've been able to see it running a web server since then too.
http://hardware.slashdot.org/article.pl?sid=05/06/06/1118242
I bet you'd also tell the team who built a replica Wright flyer a few years back that they were wasting their time, and would be better off building a Zodiac sport plane kit.
He's just a fucking script kiddie as far as I'm concerned. Real men mine and smelt their own metal. Consumer metal bought over the counter just doesn't offer enough customisability if you really want to do a project like this right.
Or even worse, they'd wire the multihop nets in a daisy chain pattern.
Hey! :)
And the low power stuff that can go months on 2 aa cells, as well!
(I've done it
That's cheating!
Brak: What's THAT?
Thundercleese: A light switch.. of TOTAL DEVASTATION!
I can imagine the pleasure he got doing this.
:-)
When I still was a teen, I used to spend full week-ends doing such nerd stuff.
I wrote a PC-compatible BIOS for my Sanyo-MBC550 (eg: here: http://www.seasip.info/VintagePC/sanyo.html/),
and was the happiest person of the world when I first got MS-DOS 5.0 to boot on it !
I also designed a simple microcontroller-based robot from printer parts
just for fun, and I was really impressed when I saw it turn around the
whole room for the first time (it could detect obstacles by sending
ultrasonic pulses).
Also, modding a 8088 motherboard to accept a second 8088 on the 8087 socket
was definitely fun. There was no cache coherency problems at that time. You
just had to invert A19 to make the second one boot at 512 kB and the bus arbiter
let them work in parallel. It was really cool to have an 8088-SMP
Those were project during which the time did not exist. I can imagine that this
guy spends his whole spare time on his project without noticing the night come,
then the day... Sometimes I wish I still had that much spare time!
Sincere kudos to him and great respect for his work!
Willy
I imagine there's some advantage of wire-wrap stuff for one-off, complex circuitry - but what's wrong with printed circuit boards?
Before anyone says they're far too difficult to make, I designed and built my own at secondary school, for a GCSE project where I built a robot. First stage - creating a computer interface! Okay, placing all the tracks and things on a computer, then laser-printing to a bit of acetate and using that as a mask for the UV lightbox prior to developing and etching might rely a bit much on pre-existing computer hardware, but it worked, and was remarkably easy.
Is wire-wrap better for multi-layered circuits, or something?
Tedious Bloggy Stuff - hooray?
From the size of the thing I wonder where the beer goes? It'd take a lot of ice given how toasty I'm guessing it gets.
2Gb RAM, 3GHz CPU, 20Gb of disk - Windows Vista: 1
4Mb RAM, 4MHz CPU, 500Kb ram disk - Minix: ?
Deleted
We do the same thing at my university in a course called "Computer Architecture". Well, not quite the same thing. We use FPGAs and Verilog to implement the CPU, and instead of a microcoded CISC CPU we implement a RISC architecture.
Since our design lacks cache, the CISC architecture that this guy implemented may be faster (it does more per instruction which is critical when instruction fetch time dominates.
However, our RISC design is fully 32-bit (registers, ALU, address and data buses) and is pipelined (classic 5-stage fetch/decode/execute/memory access/register write). We also have to deal with hazards (resolved by forwarding or pipeline bubbles). We're even working on a VLIW version now.
Of course, all of this is vastly easier when you can use a high-level hardware description language. Hats off to this tinkerer.
But still impressive.
Most peope these days dont even know what a CPU really is, other then 'quad bla bla bla superduper socket bla bla' from intel or amd.
Once upon a time, this is how it was done. Stuff like this should be mandatory for all CS students ( might be still for the few of us EE's out there, but ive not been in school for a LONG time so things could be different )
---- Booth was a patriot ----
...but I just don't have the time anymore. And my specialization is going towards nanotech. I'm not really sad, just sayin'...
And who knows, maybe when I retire....
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
But Dr. Tanenbaum's book on operating systems, which still seems to be in print, came equipped with its own version of Minix on a floppy disk, and you could easily get it going on your 808x-based PC--which was just about all anybody had when I was first reading the book. That would have been mid-to-late Eighties, but it had been around for a while even then. I'd have to go along with people who say Minix is an uncle of Linux--or maybe an auntie. If I could save only two vintage computer books, that would be one. The other would be my treasured old edition of "Oh! Pascal!"
"Here's what's happening. You're starting to drive like your Dad..." - Red Green
can it run Linux?
This side up.
Anyone who's spent time debugging their FPGA designs in a lab, going bleary-eyed staring at timing diagrams, can attest to that.
However, something has to be said about wirewrap in educational settings: It's a lot easier to make out the connections of a macroscopic object that you wrap yourself, than staring at a colorful diagram of what your usual FPGA route plotter comes up with.
It's an order of magnitude harder to do this with wire-wrap and 74xx series ICs than it is to do in an FPGA.
The guy did a nice job of documenting it, too, and the finished product looks very professional.
The old school front panel is a nice touch.
I didn't read far enough to tell if it's compatible with an existing machine, or whether he designed his own instruction set. Either way, writing a microcoded instruction set is not a trivial task. Then he needed an assembler and compiler for it. Then, he had to get Minix to compile and run. Very neat. He does mention that he's a software developer for HP. I suspect H & P are looking down on him, smiling.
Nice job.
But I think that the move to "games console-style" PCs that only run whitelisted software will be more likely to be forced on consumers by future Internet connection requirements, rather than by CPU manufacturers. ("For your protection against viruses and malware, your ISP now has a legal obligation to refuse to allow your computer to connect to the Internet unless you are only running software approved by the Digital Restrictions Ministry.")
>north
You're an immobile computer, remember?
and minix copied unix, which copied multix.
Windows copied Macintosh, which copied the Lisa (also from apple), which copied the Xerox Alto and Star, which copied the oNLine System (1965).
If by "copied" you mean "got ideas from." In science this is not considered cheating. It is considered doing your homework. If you don't look at other successful designs before making your own, there can be no progress. We'd end up reinventing the wheel 100 different broken ways, instead of coming up with better and better iterations on the same theme.
Linux was "inspired" by Minix, but succeeded in its place because of higher performance and a more open development environment.
Looking at it, the gifted ones are still doing cool original work, that requires intricate knowledge about how all the pieces fit together, then doing new stuff with it. Just we have become blase about it. Look at this weekend's Darpa robotic challenge for an example. Or the solar decathlon, self powered homes plus power the family car. Coming up with brand new materials-nano everything-that will change the world just as much as vacuum tubes and transistors did. Everything they are doing is "from scratch", because it hasn't been done before. Like the tongue in cheek observation up above, "What, they got to use refined metal? Why, back in the day..." and etc.
Seriously, you could probably get a customized version of the early kernels to compile on this quite easily... Fluxbox anyone? If they manage to run Compiz Fusion on this thing, nobody will be able to call Compiz junk that takes up resources ;)
If I were going to make a computer myself from a medieval technological standpoint, I'd make it out of vacuum tubes. It's really the only way (well, discounting relays, but I guess if you can make relays you can pretty much make vacuum tubes...).
The other parts aren't that hard. You have capacitors (just need sheets of metal foil and paper for between them), inductors (coils of wire), resistors (again, wire), and diodes (basically just a simpler version of a vacuum tube... i.e. without the grid).
If you look at some of the intricacies of medieval jewelry and such, I wouldn't think it's too much of a step to make vacuum tubes.
Like this: first, learn to make copper wire. Next, make a chemical battery. Then, use the battery technology to develop permanent magnets... Make a lot of money by selling excellent "artificial lodestone" compasses to everyone. Buy more slaves. Then, wrap the wire into a generator coil, along with the magnets. Using water-wheel technology, you now have a reliable source of (at this point alternating current) electricity.
Next, make diodes:
Learn to blow glass. Put two electrodes in a glass bottle with a heater coil on one of them, and also a valve connected to a tube. Fill the bottle with mercury, then using just gravity, you drain the bottle of mercury without letting air in: this can create a good enough vacuum to make the diode work. The only difference between this and a vacuum tube is that there's no "grid" between the electrodes.
The heater coils can be heated with the AC generator, and these diodes can be used to convert your electricity to direct current, enabling you to more cheaply produce magnetic compasses in order to fund your purchases of slaves.
Simply train them to make you more vacuum tubes, and you can make a computer! In the middle ages! Also, your diode/vacuum tube technology is the same needed in order to make light bulbs.
Really, in order to make a computer using medieval technologies, you'd need slave labor, or serfdoms (which is the same thing).
I mean, there's pretty much no way a man can be expected to make enough vacuum tubes to make even a simple computer... I'm thinking it'd take you thousands of tubes...
His web site can be found here
The story about how he got that nice enclosure is amazing too (see here) -- some guy in England read his site, thought it was a cool project, and made one and sent it to him. Pretty amazing if you ask me.
By chance are you referring to the University of Arizona? I'm actually taking ECE369 - Computer Architecture, and our semester project is to design and implement a CPU in Verilog and synthesize our code for a Xilinx Spartan 3.
:)
The assignment is to implement single-cycle, but if we implement multi-cycle, we get out of the final
who teaches you things you shouldn't know at such an early age.
How we know is more important than what we know.
This was about five years ago and he'd implemented a 16-bit (instruction and data) computer entirely through TTL, with wire-wrap. It included enough to do RS232 so you could telnet into it, although it certainly didn't have anything like an expandable bus. They'd written a tic-tac-toe game for it, and it was pretty good.
The really odd moment was overhearing the hardware guy talking to one of the software guys, who was bemoaning the lack of a logical shift-right as opposed to a bitwise shift-right in the assembly code. The hardware guy sat down, drew a couple of things, and said, "yeah, we can add that with four gates." Wouldn't THAT be nice, to be able to spend two hours wiring, and add a new assembly instruction to your processor?
I wish I could find links: they're all members of the Denver Mad Scientists' Club, but I can't find anything on their homepage.
Nostalgia's not what it used to be.
Verily! Most old SPARC cores, up to UltraSPARC, have their RTL source code open for download for exactly that purpose. So throw that on an FPGA and have at it. Toss linux or minix on their, and you're running open software on open hardware. I can think of nothing sexier.
Although I can't deny that a home-wired CPU is badass...that's a lot of free time...
Nice job, but if he was a real "man" he wouldn't have used advanced circuits like TTL. He should have wired it using 2N3904 and 2N3906 transistors using RTL (Resistor/Transistor/Logic) instead of taking the easy way out and using that new-fangled TTL stuff. And when he gets real serious, he can start with triode tubes (ala Eniac / Multics), then he will really have demonstrated his manhood (or lunacy).
At least not if you want tubes that might operate long enough for the computer to actually get through boot sequence.
While tubes are simple in concept, the amount of chemistry, metallurgy, and material science that went into making reliable vacuum tubes was simply astounding. Particularly for applications involving hundreds or thousands of tubes (like computers), achieving very high tube reliability is key to getting the computer to run long enough to actually crank outa few calculations before a tube fails.
Tubes that were designed for computer service needed ultrahigh purity metals, particularly nickel for the cathodes. The level of vacuum needed is FAR higher than you could get with a simple mercury siphon pump (think turbomolecular or oil diffusion pump). Exotic metallurgy and coatings are needed to produce grids and plates that don't emit their own secondary electrons. Cathode coating chemistry was jealously guarded by most manufacturers, and also critical to decent life.
All of this stuff is pretty much a "lost art" these days, and it is likely that nobody will EVER be able to duplicate the quality of the best tubes of the past, as most of the people who did it are now dead. While you can make a triode that will function as an amplifier with rudimentary glassblowing skills, making a tube that will reliably work in a high speed pulse switching environment such as a digital computer takes a great deal more knowledge and infrastructure.
Tube manufacturing was every bit as complicated as semiconductor manufacturing is today.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
Why in my day, all we had was a little pencil lookin' thing you had to turn yourself and we LIKED IT!
Now get off my lawn!
To boldly use to and too two times and get it right too! They're not gonna believe their eyes when they see it there!
this project has been in process since about 1980.
Thus, 27 man years by one person == 6 man-months
by 54 people which sounds about right for the
original 8086.
Fixed
Everyones a troll, I just have the balls to admit it!
old SPARC cores
UltraSPARC
RTL source code
throw that on an FPGA
linux or minix
open software on open hardware
I can think of nothing sexier.
99.99% of the planet thinks you are just weird.
Not clustering, I mean Beowulf, the movie I just downloaded. No? Then what's it doing on Slashdot?
(yes, I'm being silly)
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
University of Colorado at Boulder.
ECEN4593. We're also using Spartan III FPGAs, which are more than sufficient.
Our CPU architecture is called "SRC", for "Simple RISC Computer". It was designed by a professor here. It's a full CPU (somewhat similar to MIPS) but has some notable shortcomings (no condition codes, integer only, no multiply/divide) to make the ALU simpler.
"Linus was inspired by Minix and used it as the initial development platform for Linux" == Informative
"Linus has copied Minix!!!1111one" == Troll
Consider the difference between serving a cake, and throwing it into someone's face. Sorry for not using a car analogy.
Mod GP back to troll, please.
WYSIWIG, but what you see might not be what you need
I remember we had to make a 1st and 2nd order differentiator for one of our first senior labs. Differentiators are annoying because their gain increases with frequency. Naturally, there was a bandwidth spec, and a phase angle spec at the endpoints of that bandwidth. What the wiley profs where expecting us to all go do is build low pass filters and learn how, say, the bizarre phase behavior of a Butterworth filter could really ruin our day.
My lab partner and I remembered learning about "gain-bandwidth product" and how it applied to good ol' 741 op-amps. Basically, what that says is the more gain you ask for out of an op-amp, the less bandwidth you get. Above that point, the frequency response falls off. Given our input and output impedance specs, we settled on a very simple differentiator design that consisted of two op amps separated by a simple RC differentiator. (Capacitor in series, resistor to ground.) We then set the gain on the two op-amp stages so that the end-to-end gain was the specified gain, but the first-stage gain was so high that the op-amp effectively band-limited the signal, thereby giving us our low-pass filter.
Needless to say, everyone was astounded that we had only 2 747's on our board (each 747 is the equivalent of two 741s), 10 resistors and only 2 capacitors, and we were fully in spec. Everyone else had at least twice as many op amps and all these silly 2-pole filters everywhere, and were having a hard time hitting spec. Oh, and we only took half the day.
Sadly, we got a C on that lab initially because our writeup sucked. We didn't adequately explain our design or how we achieved our results. (I think this may have been our first or second real lab in senior lab.) The professors were duly impressed though. :-) We were allowed to go back and amend our lab notebooks with more thorough documentation. (In fact, we were required to.) We subsequently got an A on the rewritten lab.
--JoeProgram Intellivision!
"This project shows that fundamental computing technology can be reproduced with relative ease on a very small scale with limited resources"
Well, that depends on your definition of 'reproduce'. Reproducing wire-wrapping or something similar should be relatively easy, but TTL ICs do not grow on trees, you know. Even with these in hand, it will be a major effort to make things work without such tools as a simulator, EPROM programmer. I also doubt that it would be relatively easy to write a C compiler and an operating system from scratch (no cross-compiling)
That 99%+ of us don't find it funny. Seriously, every now and then somebody comes up with a decent "overlord" joke or whatever, which might be useful for a dry chuckle. The majority of the time it's an attempt to get a post in and the actual humour of that particular would-be-joke category has long since fled.
Let's time how long it takes to fully boot the OS...
I wouldn't be entirely surprised if the homebrow minux machine comes out ahead.
REAL men create their own universes, this second hand stuff is just for kiddies.
Grow a pair, GOD.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
It says NOTHING about his sexual activity.
Basic logic people. If it rains I carry an umbrella, this does not lead to, if I carry an umbrella, it rains. It does not even mean that it can't be raining if I am not carrying an umbrella.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
With some extra cooling, maybe this machine could be overclocked to, say, 7 or 8 Mhz. Then you could start to run some more powerful applications on it. Anyone for Eclipse? Or MS Word under Wine? And for that truly Spinal Tap experience, there should be a knob to turn the overclocking all the way up to 11 so its web server can rock out even under a slashdot-imposed load.
If Scott Adams hears about this project then it might make it into Dilbert. I imagine Dilbert would construct one of these, show it to colleagues, and then his pointy-hair boss would say "Good prototype. Now miniaturize the parts to fit into a laptop and we'll sell it at a price point to compete against the Asus eee."
4Mb RAM, 4MHz CPU, 500Kb ram disk - Minix: ? Wow.... 2 gigabits, 20 gigabits, 4 megabits and 500 kilobits.
Capital letter 'B' is for bytes.
At least 'Hz' was spelled right. That's another one most folks fuck up.
Sorry for being so anal about this but this is something my high school physics/chem teachers were extreme sticklers for and I agree with them. In their fields a misspelled unit is all that's needed for potential disaster.
Look, that comment made me laugh hardest of all because of the unintentional irony. It's an absolute gem.
:-).
I *love* people making unintentional mistakes like that, but hell, I'm twisted.
Just not bitter
Insert
The original 74 series were TTL chips definitely implementing digial logic, albeit at rather a lower level of integration. Later people went to 74LS which was lower-power but faster, I had heard on some people doing analog things with a TTL chip but it would be rather unusual.
I'd like to take this opportunity to point out to everyone that keeps saying "I've done the same thing with an FPGA", you haven't done the same thing. At all. Even a little bit. Unless of course you built your FPGA out of discrete 74xx series TTL components and wirewrap.
Abraham begat Isaac; and Isaac begat Jacob; and Jacob begat Judas and his brethren ...
...
...
... yadda, yadda, yadda,
... and Multics begat Unix; and Unix begat Minix and his brethren; and Minix begat Linux
so to do a proper FPGA design, you really DO need to understand things such as race conditions
Race conditions are not an issue in a synchronous design because the transiant states don't matter as long as everything is settled by the next clock (which the timing analyser built into your synthisis tool should tell you provided you set the tool up correctly)
fan-in, fan-out
Theese are the responsibility of the synthisis tool.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
I really think your blowing smoke on this one:
:-)"
"Also, modding a 8088 motherboard to accept a second 8088 on the 8087 socket
was definitely fun. There was no cache coherency problems at that time. You
just had to invert A19 to make the second one boot at 512 kB and the bus arbiter
let them work in parallel. It was really cool to have an 8088-SMP
The second 8808 would boot ROM BIOS, and start spitting up on the default monitor, copy the intrupt table to 08000, but would only have 128k to work with, the first intrrupt it hit, to load from a disk, would start both processors running on return from the INT. In fact you could just easyly hang this box with INT-20. both processors would be executing the same code at the same time. It would only be a matter of seconds before some interlock hung the machine. It would be a really fun thing to watch. But WORK? NIFMY.
Do you catch a lot of people with this one? OR
Do you catch more people with the Sanyo BIOS rewrite? 8k certainly isnt enough room to fix the video card IO problem.
Okay, so this guy went back in time 40 years and recreated what probably happened on some Intel engineer's workbench waaaaaaay back.
Pardon me while I go write a BASIC interpreter for the Altair 8800; I mean, my name IS Bill, after all.
-Billco, Fnarg.com
And 0.01 % thinks that he is sexier than open software on open hardware... leaving none to agree with him!
At 4Mhz, imagine a Beowulf cluster of a Beowulf cluster of these.
Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong fix.
Back in the mid-80s at CU Boulder, this was exactly what we did in a 400-level EE class called "Computer Lab".
My group's design divided the primary clock into 10 phases, for each of 10 execution phases. We had 8 (I think?) 2716 EPROMs for the microcode, and a pile of 74xx chips. We designed the primary clock to run at 10 MHz, giving us one instruction execution per microsecond, but we had problems with clock rates higher than a few hundred Hz.
When we were disassembling, we found an open-collector part with no pull-up resistor in the clock path. We were pretty lucky it worked at all, but we ended up with a pretty good grade. About half the groups didn't get anything running at all, but we were able to get a simple counting program to run. One of the crew even found a cheap synthesizer circuit we could put in place to have it count out loud ... very, very slowly.
My own worst contribution to the project was not getting the assembler completed, so we had to hand-assemble the demo program.
My hat is off to Buzbee.
I had forgotten how much cooler teenagers look when they are smoking. Oh, wait
In some of the pictures all of the wire wrap is blue... It's been a while, but I remember wire wrap being available in many colors... colors you can use to code different things (i.e. address bits, using resistor scheme). Anyway... amazing, really takes me back 20 years ago to my college days. Props
Senior Project?! At my university, Rose-Hulman, Computer Scientists, Software Engineers, and Computer Engineers take a class, Computer Architecture, in which they design a CPU, and the only prereq is ECE130: Circuits and Systems, which can be taken as a first quarter Freshman! I think this project would be a sophomore level project at most!
---- "XML is like violence. If it doesn't fix the problem, you aren't using enough."
Like all modern applications, /. emulates the "funny" flag with 100,000 lines of XML.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Why not implement, just for the hell of it, a switch on some old mobo that could slow the CPU down by a factor of a million or two, and then rig a panel full of Blinkenlichten (http://en.wikipedia.org/wiki/Blinkenlights) to the bus, flip the switch, and turn down the room lights and enjoy the fun.
Would a Pentium still work, underclocked to a few thousand Hz?
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
...I get a kick out of FPGAs.
I was with Data General for 14 years. Went from TTL to PALs and then did CPLDs and FPGAs for 3Com. Being able to build an entire design inside one chip by writing code *absolutely rocks*! And there's no more rework at the lab bench...just retype, resimulate and go!