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Comment: Re:That makes no sense. (Score 1) 156

by geoskd (#47425331) Attached to: Ask Slashdot: Best Dedicated Low Power Embedded Dev System Choice?

How much does it really matter when a small project will only take 15 seconds to compile on the BBB. So what that a cross-compiler can do it in 2 seconds. it'll still take close to 15 seconds total when you include the time to type the commands to download the executable. Even if it was only 7 seconds, it is still only a negligible gain.

now if you were compiling a kernel, or god-forbid something really big like open-office, or some such then I could understand, but for the vast majority of embedded work, it just doesn't matter. The embedded devices are fast enough.

Comment: Re:Save yourself some pain ... (Score 1) 156

by geoskd (#47425179) Attached to: Ask Slashdot: Best Dedicated Low Power Embedded Dev System Choice?

If you are building a project which requires some special hardware then you don't have to waste time porting a driver from x86 to ARM, MIPS, Sparc, etc.

In my experience, most embedded machines these days are ARM, and finding x86 ports is more of a challenge. Between the explosion of ARM based cell phones, and the Rpi/BBB, x86 is becoming less and less relevant (and with it MS/Intel)

Active android development is almost all ARM, and x86 is ported as an afterthought.

Comment: Re:With Ubuntu. BBB (Score 1) 156

by geoskd (#47425135) Attached to: Ask Slashdot: Best Dedicated Low Power Embedded Dev System Choice?

The new BBB version is popular and hard to find but the extra flash is nice.

How many do you want? These are not from Beagleboard, and are not Beagleboard certified, but they can be had in almost unlimited quantities and work as advertised. They are manufactured to the open specs. They are being manufactured by a third party in China in vast quantities for commercial use. They cost more than the official versions mostly because you can actually get your hands on them from these guys in nearly limitless quantities (up to 100+ they have in stock to ship right now, more than that might take a day or two, and order for a couple thousand might actually take them a week, but i doubt it) Rumor has it they are moving more than 100k units/month

Comment: Re:BBB (Score 1) 156

by geoskd (#47424901) Attached to: Ask Slashdot: Best Dedicated Low Power Embedded Dev System Choice?

Because of the poor reliability of MMC, I prefer to use SSD these days

MMC reliability is fine. I thought I was going to have problems using the MMC on the BBB as well, so I set about beating several of them severely. I setup accelerated read-write-read testing, and started pounding on the BBB internal MMC. with 3 boards at over 5M writes to a single 512Byte block each, none of the devices failed. I read some literature which suggests that the MMC rotates sector usage to even out wear, which, if true, means that you would have to do the equivalent of recording 100,000 hours of HD video before you will burn out the MMC.

The other issue with the Beagle Bone is that the processor is kind of on a dead end in terms of development cycle. That is, TI is not actively developing new OMAPs, but they have been authoring most of the Linux drivers for these chips. TI will continue to produce the OMAPs that are on the Beagle Bone, but I wonder how much they will continue to support driver development for future Linux.

Embedded devices are install and forget machines. It doesn't matter much who supports them or doesn't once they are in the field. As far as unit availability, Special Computing is ramping up production and already surpassed all the other BBB manufacturers combined. Last I heard, they were over 120k per month production, the vast majority of which is going into mass-production doo-hickeys from various manufacturers. Our own embedded system uses 1 or more of them in every unit we sell.

The biggest advantage to the BBB (and to a lesser degree the Rpi) is time-to-market. An embedded system used to take 3 to 4 years to develop from conception mass-pro. With the BBB, we were able to do an entire embedded system, From absolute zero to mass-pro in 18 months. The case took longer to design than the embedded hardware!

Comment: Re:Solaris not well supported by OSS toolchain (Score 1) 156

by geoskd (#47424749) Attached to: Ask Slashdot: Best Dedicated Low Power Embedded Dev System Choice?

Which to anyone that has actually DONE this sort of development is nonsensical.

I happen to like doing my dev work directly on the BBB. I have a full scale machine that I use as a glorified display, and other servers that house subversion, and other needed resources.

Doing dev work directly on the BBB makes it far easier to deal with debugging problems in the field, because, by definition, I have my full debugging environment with me at all times. My dev environment is always exactly identical to the production environment, so I never have the "it works fine in the lab" scenario.

Sure it may take longer to compile, but I can take a virgin board, and have my dev environment up and running anywhere anytime. Give me any laptop with an SSH client, and I have a full dev environment. It is also much easier to debug embedded hardware problems when the development and production machines are the same.

Comment: Re:Solaris not well supported by OSS toolchain (Score 1) 156

by geoskd (#47424643) Attached to: Ask Slashdot: Best Dedicated Low Power Embedded Dev System Choice?

The GPP is 100% right when he says "Just because you don't understand their needs doesn't mean you need to step in and try to change what you think they need. (Ever think they just MIGHT be smarter than you or know their needs better?)"

Which once again returns us to the basic questions being asked by the would be helpers: "What are you trying to accomplish?" Without that fundamental part of the picture, all but the most generic help is pointless.

To return to the current case in point, Say the person is trying to build a plant monitoring doo-hickey. The choice of platforms depends a great deal on a hundred little specifics. For example, if each device being designed will handle one plant only with just a few sensors, and it is going to run on a non-trivial power source (car battery, wall power, large-ish solar panel, then a Rpi is probably the best choice. If the device is going to monitor a row of plants with sensors, then a BeagleBone is probably a better choice for its expanded IO. If it has to monitor an entire greenhouse with dozens of rows, then perhaps a distributed collection of 1 wire sensors is in order in which case just about any platform will do. If, on the other had, the whole thing has to run on a pair of AA batteries, then you are going to have to roll your own solution, and some kind of FPGA board would be a better bet, since you're going to need to understand where every bit flip is going to keep the power consumption down.

The original questioner did not provide enough details to suggest that they even understand all of the options available, so it quickly becomes clear that further questions are needed to find out what they do and don't know.

Key questions that need to be answered:

What does "low power" mean? 5 watts, 0.5 watts, 50 watts?

What does embedded mean? Is he referring to embedded to mean that it is a headless device? Does he mean that it has to run from a limited power source? Does he mean that he needs a device with GPIOs?

In what ways will the device interact with the world? By Ethernet? by 1 wire? by dedicated GPIOs? Does the submitter even understand this question enough to answer it? I'm not so sure from the way the original question was phrased

How many of these device does he intend to build? Just the prototype? Low volume run (Less than 100 units)? Mass-Pro?

In conclusion, the question was not properly framed, most likely because the submitter did not understand the topic well enough to ask intelligent questions, and samzenpuss sure as hell doesn't understand the topic well enough to properly filter these kinds of questions.

Comment: Re:And how many do they need? (Score 1) 97

It's users are arguably less technically savvy. Can you imagine the cost with establishing a secure 1 million user network, where Linux isn't an OS but more probably some disease that was eradicated back in the 1800s. Training would cost so god damn much, take a year or two. Sure, probably don't need IIS servers. But users need to be on Windows.

But every couple of years, MS hands out a perfect reason to convert: New versions.

The cost of retraining to use Windows 8 for example is probably going to be on par with retraining to use Ubuntu or Debian. It could probably even be reduced for Ubuntu or Debian by using a more windows 7 like GUI to help keep the environment as familiar as possible. Any organization that cites conversion retraining costs as their primary cost justification for staying with MS now is either lying (to cover a conflict of interest, bribe, etc...), or incompetent at doing cost analysis.

Comment: Re:Obviously (Score 1) 538

by geoskd (#47290553) Attached to: Teaching College Is No Longer a Middle Class Job

If that were true, tuition would be in free fall.

Not so long as the true costs are deferred until the consumer no longer has any choice in the matter. If you didn't have to pay the loans back if you couldn't find work in your field, then the cost would be in free fall because so many people wouldn't be required to pay back the loans.

Demand is kept artificially high by hiding the true cost, false advertising, and a corporate greed machine that is almost custom built to drive wages down, and job requirements up.

Comment: Type of applications (Score 1, Insightful) 466

by geoskd (#47240817) Attached to: Ask Slashdot: Best Rapid Development Language To Learn Today?

It all depends on what kind of applications you need to write.

If you're looking to write back-end or network applications that do not require a GUI, then I would still recommend C++ with one caveat. Get and use the Boost libraries. You will find that these libraries fix most of the crap that was broken about C and C++. C++ is not necessarily the easiest language to use, but you already know it which is a tremendous advantage.

If you need to do front end / GUI development, I recommend JavaScript. Not because its easy to use, but because web browsers are everywhere, and largely platform agnostic at this point. There are plenty of systems out there that build on top of JavaScript, and any of them would be worth a look.

Comment: Re:IPv6 Addresses (Score 2) 305

by geoskd (#47226055) Attached to: When will large-scale IPv6 deployment happen?

Worse, when you change your password, and are told that the new password is unacceptable because it's too similar to your old password. That means that they're actually storing your password, and not a hash. And they think that's secure?

You might not have noticed, but password change utilities always require you to enter the old password as part of the change process. That means there is no need to store the old password for comparison, you have just entered it, and it can be discarded as soon as the comparison is done.

Comment: Re:IPv6 Addresses (Score 2) 305

by geoskd (#47225995) Attached to: When will large-scale IPv6 deployment happen?

This response always pisses me off. What do you do when DNS is broken? What do you do when you are the guy setting up DNS services? With IP 4 it is pretty easy to remember a 4 number string long enough to transpose some addresses. It is easy enough to remember a small handful of well known DNS servers' addresses so that you can get a machine talking on the Internet or on your local network. IP 6 has a short-hand notation, but it's still a pain. Looking at the example given, when transposing that address one has to hold in mind 5 sets of variable-length numbers (in Hexidecimal, no less) and remember the location for the double-colons.

Short answer: write it on a piece of scrap paper, or put it into a note on your tablet|phone|pda.

My god, are we so enamored of our technology that we have abandoned the pen and paper?

Comment: Re:Raise the Price (Score 1) 462

by geoskd (#47082465) Attached to: Fiat Chrysler CEO: Please Don't Buy Our Electric Car

But it is already expensive enough that it doesn't make a lot of sense to buy if you want to buy one to save money on gas. The price difference is $15350. If we assume $4/gal for gas, then that's 3837.5 gallons. Fiat 500 gas version gets 31mpg city, 40mpg highway. If we average that, then we get 136,231.25 miles before the price difference pays for itself. And that's assuming we paid cash for the car. If you finance it, then add interest on top of that.

The Gasoline price difference is only a part of the cost savings, and it isn't even the majority. The fact is that pure electric vehicles are much cheaper to maintain. They have no oil, so you can scratch off $200 / year in oil changes. There is no rotating alternator, no starter, of fuel pump, no oil pump, no water pump, No distributor cap. The single biggest difference is a lack of wear and tear on the brake pads. A *properly* built EV will have full regenerative braking which effectively prevents the driver from *ever* using the brake pads. (most EVs today do not have full regen braking, and instead use the brake pads part of the time. This is a result of incompetent design engineers who still do not understand electronics, and insist on a mechanical solution). A typical EV will go 5 years between maintenance visits. I have had mine for two, and the dealership offers "free oil changes for life" on all of their vehicles, So i take it to them once every three months, and they top the windshield wiper fluid and wash the car. Outside of that, there has been no maintenance at all since I bought the car, and the first sched maintenance (according to the factory) isn't until 100k miles when they will check the control diagnostics to see if everything has been running correctly. I get the brake pads every year at the cars inspection, and every year they comment that the brake pads look essentially brand new. They don't expect I will need new brake pads until somewhere well north of 100k miles.

At the end of the day, the cost for the first 5 years are a little cheaper for the gasoline car. You have $250/ month for car payments, plus $80-100ish for gas, plus $40-50/ month for maintenance (oil, brakes, etc.

The comparable EV will cost about $500 / month in payments, plus $25 / month in additional electric costs.

Total Gas: $370-$400 / month. Total Electric: $525-$530/month

After 5 years, the cost dynamic changes radically. The two car payments go to 0. The operating costs for the EV remain around the $25 / month in electric costs. The monthly cost for the gas vehicle actually go up. You still have $80-$100, and you still have the $40-$50 for regular maintenance, but now things start to break. You have an additional $100 / month for unexpected maintenance, (maybe twice a year, something like an alternator goes, costing $600, maybe you accidentally fry a brake rotor, so that $100 brake job now costs $500.

5 years to 10 years old: Gas car: $220 - $230 / month. EV: $25 / month

After 10 years, it gets truly ugly. The gas can now has major mechanical trouble on a regular basis. The total average monthly maintenance costs are up over $250 / month, and most people consider it cheaper to replace the vehicle. The EV on the other hand is still in perfect working order, and there is no particular reason it should have significant costs this decade. The only two parts to suffer any real wear and tear are the motor controller, and the motor itself, both of which if designed properly, for the EVs usage profile, should last many decades. The motor controller will eventually fail due to a phenomenon known as silicon fingers, but in large quantities motor controllers would be very cheap to build. ($300 or less, and it should be at least 2 decades before it fails.)

Comment: Re:So... (Score 1) 630

by geoskd (#46709471) Attached to: Navy Debuts New Railgun That Launches Shells at Mach 7

1/2mV.terminall^2 since 83 miles away we presume it will be on the downslope of a parabolic-ish arc. 23lb at 300mph - 10kg at 136m/s = 10 x 136^2 = 185kJ give or take. So about the same as a Toyota Yaris going 40mph or a Ford Focus going 35mph.

These things will be going much much faster than terminal velocity, even 100 miles downrange. They simply will not have enough time to slow down. The shuttle on re-entry came in basically belly-into-the-wind to bleed of energy as fast as it could, and it still took a half hour and 6,000 miles to bleed off all that energy.

This shot is designed to be stremlined, and will not bleed very much energy at all. I wouldn't be surprised if its still moving mach 6 when it gets to its target... Try redoing your calculations for 4,000 MPH, and see what you get.

Never underestimate the bandwidth of a station wagon full of tapes. -- Dr. Warren Jackson, Director, UTCS