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Comment: Re:Performance? (Score 1) 136

by Jerrry (#47626125) Attached to: Parallax Completes Open Hardware Vision With Open Source CPU

"I wonder how this CPU performs? Does it compare to anything I'd care about, or is it more akin to something I'd build a wifi router out of?"

The Propeller is an interesting beast. It has eight 32-bit cores they call cogs and a hub that ties them all together and gives each of them round-robin access to the 32K of hub RAM. Each core itself only has 2K of RAM it can access, so any assembly program has to fit in this small space.

Most the the time, you don't write assembly code (unless you need the speed), but use Spin instead. Spin is a proprietary, interpreted language. Each cog can host a separate version of the Spin interpreter, and tokenized Spin code is fetched out of hub RAM, which is much larger than cog RAM (32K vs 2K), so Spin programs can be larger.

There's also a C compiler that has a strange implementation given that cog RAM is too small to hold more than a trivial program if the code were entirely cog resident.

One other difference between the Propeller and most other microcontrollers (AVR, PIC, ARM, etc.) is that the Propeller has no built-in peripherals. The philosophy behind the Propeller is that if you need a peripheral, you implement it in software and run it on one of the eight cogs. Need a UART (or six)? It's just a matter of software. It is somewhat wasteful, however, to dedicate an 80 MHz 32-bit processor to a simple I/O task -- that might offend some purists. Since all peripheral functions need to be implemented in software, it's not possible to directly implement peripherals that run at high data rates, such as 480 Mb/sec USB.

The Propeller also lacks interrupts. The logic here is that since you're dedicating a full 80 MHz processor to an I/O function, you can poll without affecting any of the other processors and hence don't need interrupts.

All-in-all it's an interesting and unusual architecture, but I don't see it replacing more mainstream MCUs anytime soon.

Comment: Re:Does everything need to be smart? (Score 1) 128

by Jerrry (#46665389) Attached to: Nest Halts Sales of Smart Fire Alarm After Discovering Dangerous Flaw

"Yes. That's why fire sprinklers are so successful. There's nothing between the water and the fire except a low-melting-point component in the sprinkler head."

Sprinklers are something you really don't want to fail, because both scenarios are destructive. If the sprinklers fail to work as designed, your house burns down. If they go off without a fire, you have lots of water damage, which is almost as expensive to fix as fire/smoke damage.

Comment: Re:Soul Crushing? (Score 1) 276

by Jerrry (#41206387) Attached to: High Tech Companies Becoming Fools For the City
Well, here's what I think they're after: City centers (assuming there is a city center, not all cities have them), tend to be areas filled with the things that make the city unique: tourist attractions, public artwork, nifty historical architecture, headquarters skyscrapers of well-known businesses, etc.

Yes, but they're also full of bums/beggars, filth, graffiti/grime coated buildings and streets, noise (constant car horns and sirens), congestion, bad smells, crowds, long waits, and many other reasons why many people prefer to live in suburbs.

Comment: Re:Is Apple really that great role model? (Score 1) 462

by Jerrry (#40118639) Attached to: Free Desktop Software Development Dead In Windows 8

"It seems like with this move and generally the Metro and Windows 8 walled garden stuff, Microsoft is going more and more "the Apple way". "

If, by the "Apple way", you mean iOS development, then I'd agree with you as the App Store is the only viable means of distributing apps short of jailbreaking an iDevice.

This is not the case with OS X apps, however. Sure, there's an App Store for the Mac, but it's not mandatory like it is for iPhones and iPads. Plus Xcode, the Apple development tool, is free and this tool is not an "Express" version like the free versions of Visual Studio. The underlying compilers (either GCC or LLVM) are open source too, which is more than you can say about the Microsoft compilers.

Comment: Re:Photographer should say "Go ahead" (Score 1) 667

""The fair use doctrine permits nonprofits more leeway than for profit businesses." - That's not true but it's understandable if she believes it is and thought no harm was done."

It would be understandable if she were an average person, but she claims to be an attorney on her web site, and as an attorney, she should know better.

Comment: Make the Fines Meaningful (Score 1) 187

by Jerrry (#37356426) Attached to: New Legislation Would Punish Mishandling of Private Data

The problem with legislation of this sort is that the fines imposed are ludicrously small compared to the revenue of the companies being fined.

If I were fined for, say, exceeding the speed limit at the same ratio to my income as most fines imposed on companies, then the fine would be something like $0.05. Hardly a disincentive at all.

Comment: Re:The likeliest adopters are commercial users (Score 1, Interesting) 241

by Jerrry (#36967620) Attached to: .NET Gadgeteer — Microsoft's Arduino Killer?

I don't love Microsoft, but kudos to them for branching out creatively in an effort to shore up their sagging fortunes.

Microsoft just announced record Q4 earnings a few weeks ago of over $17B. How, by any stretch of the phrase, are their fortunes "sagging"? I wish my own personal fortunes were sagging as badly.

Comment: Re:Cost to install (Score 1) 352

by Jerrry (#35918366) Attached to: Solar Panels Increase Home Value

"It's closer to $6k per kW in my next of the woods (that's why I paid), but I'm sure you can find a company to do it for $5k. I went with a company that had done some installations in my neighborhood, though, and had a pretty good reputation."

That's close to what mine cost ($80K for 12.5 KW). Even in summer with all 3 air conditioners running, my electric meter is still running backwards. Even it winter it's usually generating more power than we're using, expect on dark overcast or rainy days.

Comment: Re:Because.... (Score 1) 2288

by Jerrry (#35889334) Attached to: Why Does the US Cling To Imperial Measurements?

"There is no consistency, and that alone can give rise to errors"

If you think we're inconsistent, take a look at the bloody Brits.

They use cm and meters for length, except on the roads, where they still use miles (and MPH).

They use grams and kg for weights, except for people, where they use stone.

It's a bloody mess.

"I got everybody to pay up front...then I blew up their planet." "Now why didn't I think of that?" -- Post Bros. Comics

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