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Comment The 4040 and covering the history a bit (long) (Score 1) 74

The 4040 added some instructions to the 4004 and was a bit better. I seem to remember something about the stack, but it's been so long... Early BYTE magazine actually had articles with 8008 assembler I remember. The early flavors of micros were diverse. Feature rich machines were damn expensive in general. People would cobble together whatever they could, instruction sets and features of processors were actively debated. The major camps seemed to be:

-- RCA COSMAC 1802. You could build a minimal system cheaply. Speed wise this was fairly slow, but it was a real processor. Lots of registers. Architecturally it wasn't as bad as some people like to say. Yes, you could easily implement a CALL/JSR and RTS too.

-- Nat Semi PACE/IMP-16. Most of the folks who went this route seemed to want more 'mini' style features - e.g. 16 bit instruction sets. These were very slow performance wise. Minis based around them were cheaper than the big-name mini's but seemed super slow. Met people who said their early 8080 micro kicked the mini's butt in terms of performance.

-- Single & multi chip direct from mini architectures. Stuff like TI 990, DG NOVA DEC PDP 8 and PDP-11. The TMS9900 was a notable contender.

-- Motorola 6800 and Intel 8080 - Both were popular, and much faster than stuff like the PACE / IMP-16 / 1802. They were usually simpler to design against and often faster than the single chip mini's derived stuff too (excluding maybe the TMS 9900 ).

-- MOS Technology 6502 at the same clock speed was usually equal or faster than a 6800 / 8080 for most stuff. It was super cheap too.

-- Zilog Z-80 A notably enhanced 8080. Loads more instructions. Very non orthogonal. Easy to interface to DRAM. Very very popular. The Z-80 pretty much gobbled up the 8080 family. Even when the 8085 came out, people went for Z80's. CP/M & S100 bus stuff, but lots of other stuff used Z80's like home micros etc.

The 6502 also gobbled up a bunch of designs. Motorola responded with the 6809 which is a really nice 8 bit to program. But by then the world was moving on to 16/32 bit stuff.

One of the most interesting things (to me) is that the Mini folks totally screwed up and ended up being wiped out. One wonders what would have happened if DG or DEC had produced a decent microprocessor based on the NOVA or PDP-11 at a low cost. DEC sort of did this with the LSI-11, but there was always this tension of the high-margin mini stuff being eaten from the bottom up. What if they'd been smart enough to pragmatically say - our high margin business is going to get destroyed by microprocessors, do we want them to be our microprocessors or someone elses?

One thing people forget about Intel is they did a superb job of supporting their stuff / had great sample designs that made getting started easier. Motorola for the 68000 actually actively discouraged folks and banned their engineers from talking to people who wanted to use the 68000 in the early days. Read D-TACK GROUNDED for details. It seems absurd right?

The general thing seems to have been that everyone wanted the new micros to go into the nice old high-margin mini business. Except they didn't. Cheap powerful MPU's meant people didn't want to pay 10x the MPU cost for software licensing fees or other garbage. They figured out how to cheaply hook video up to the microprocessors and keyboards. They figure out how to cheaply hook up mass storage. They built what was needed, and what worked got used. Not always entirely fair - there are plenty of amazing designs that never got traction, but life ain't fair.

Comment Re:MCS-4 family, 4004 CPU--Inside View Mazor (Score 1) 74

Don't forget the 4040 either. I think they might have expanded the stack, but I am pretty sure it had better clock support for external oscillators / there were a bunch of nice glue chips which had stuff like you mentioned for IO / RAM / expansion. I think a slightly larger address space / still done with the expansion style mentioned above.

Comment Re:String theory like saying algorithm is O(n^a^b^ (Score 1) 387

I think the problem is that by the very nature of it, it can't produce falsifiable predictions (if I'm understanding the arguments correctly). If a beautiful string-theory framework could produce something that COULD produce a falsifiable prediction, I think everyone would be super-happy, but I don't think it can do that either - at least I don't think anyone has successfully demonstrated anything like that.

It been more than 40 years and nobody seems to have done that. Compare that with any number of other 'beautiful frameworks' that produced falsifiable predictions (e.g. Relativity (both Special and General)). Even the weird stuff has often produced falsifiable predictions.

I'm not even sure what string-theorists think the end-game is. Do they actually believe they will discover some new theory of everything? Or have they given up?

Comment String theory like saying algorithm is O(n^a^b^c) (Score 1) 387

A theory that can't predict anything, that has an automatic 'out' seems pathological. String theorists may point out that they have proven that there are only so many consistent parameters for their theories, but it still seems there are no falsifiable predictions.

It's like someone saying the time-complexity of an algorithm is O(m^a^b^c). You then say - wtf? and they say 'Great news, we've proved that c can only be between 9 and13!. You then say integers? and they say 'Uh, NOOOOOO you idiot, obviously they are rational numbers. Did you know that c=9 7/13 has some fascinating characteristics!. So you then say what about a, b and c and they say 'rational numbers between 4-8'... we think.

Submission + - Help Save Arecibo Observatory, World's Largest Operating Single-Dish Observatory (whitehouse.gov) 1

earth2allie writes: The National Science Foundation has recently discussed the possibility of closing the Arecibo Observatory (http://www.scientificamerican.com/article/world-s-largest-radio-telescope-faces-a-troubling-future/). This facility is used for ground-breaking research in the fields of Radio Astronomy, Aeronomy, and Planetary Astronomy. As an astronomer myself I can tell you it is truly one of its kind, and the Arecibo community is asking everyone to take action by signing the petition to keep it open. Help us save Arecibo!

Comment Game Changer; Best-defense? Nuke your own airspace (Score 2) 208

This is great for defense. Unlike some people have said, you don't need to physically destroy the entire missile engaging you. For IR heat-seekers, you just have to blind the seeker. For radar guided missiles, deform the radome. Missiles tend to travel at high speeds, if you can screw up the radome or any part of the structure sufficiently it'll make a big difference to the attacking missiles pk (probability of a kill).

Your same offensive weapon makes an awesome countermeasure against HOBS (High-Off-Boresight) stuff that someone might launch using a HMCS (Helmet Mounted Cueing System). If you have decent secure networking, there's no reason why a bunch of your team couldn't target the same target too. So instead of being hit by one laser, you hit the target with N lasers. The enemy having better kinematics becomes moot too. A rotating mirror can rotate much faster than even the most maneuverable airframe.

The best countermeasure to this stuff if you don't have equivalent stealth? It's tough. You can't detect attackers well enough to get a firing-solution, you have nothing on your warning receivers for your team. Best case, let's say you know somethings up there due to VHF radar. So you send up your stuff, and all of them just get swatted from the sky. You ask your best engineers what to do about it, and they say 'Our best idea is to make the environment so nasty we deny the enemy access'. How do you do that? Nuke your own airspace. If you can't see the enemy but your assets start exploding, fire off a pile of SAMS (in nice solid reflective casings, no fine guidance necessary) and nuke your own the airspace.

If they are at altitude then that's one thing (not much fallout). If they are using terrain shadowing / strike teams going in to take out your ground assets, then you are talking about basically carpeting yourself with fallout.

Comment "Progressives" who don't believe in democracy. (Score 1) 387

It's fascinating to me how many people who purport to believe in democracyare so keen to strip others rights the second the front-runners don't fit their views.

At least the right leaning people seem to admit what they want (less government, less taxes, leave me alone, less intervention). Yet many of the left-leaning "progressives" are in such a state of double-think they don't even realize they are sprouting propaganda.

Just the term "progressive" is propaganda. Being "progressive" about denying others their rights when the views don't align with their own is NOT progressive. It's repressive.

Comment Re:Artillery versus Airplanes (Score 1) 206

Thanks for sending that. I was thinking a little about Plumbbob and the steel-plate as I typed the Orion comment, but hadn't heard of Wang Bullet. It has all the advantages of artillery and NPP combined. Plus the reaction mass (steam) reduces the acceleration. It's awesome.

 

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