I don't see it mentioned, so I must: "The Night We Buried Road Dog" by the late Jack Cady. It is a multiple award winning novel, but it seems that Jack Cady never really got big sales or other accolades during his lifetime.
Building a shielded room is a simple idea, but unattainable in practice. An effective Faraday cage is much, much, harder to build than just lining the walls with metal- in particular, the doors would need special seals, and any effect would be negated once you open a door. You need ventilation too, right? Wires to get power into the room...
NB: Grounding won't make a difference with respect to RF, particularly at the frequencies modern communication devices run.
A Faraday cage that big (and effective) is extraordinarily expensive. RF is very effective at making its way through tiny holes. It is even more difficult once you start including doors that open and close frequently. And your microwave's RF seal is not nearly as effective as you think.
My (3rd party observation, of course I wouldn't do this) is that the drivers look at their phone for a second and put the phone down. My supposition is that they realize that their conversation is not so important-- it can wait until they are no longer driving. Using a jammer is passive agressive to be sure, illegal in many jurisdictions, and can be very rude. The user of such a device must be prepared to accept the consequences. A better solution would be that people pay appropriate attention while driving.
I've seen the effect upon drivers talking on their phones while driving. While talking on the phone, their speed is erratic and inconsistent, they wander around their lane. Once in range of such a device, they look at their phone for a second or two, put the phone down, and start to pay attention to the machine that they are controlling. Once their conversation ends, they have become much more responsible drivers, aware of those that are sharing the road with them.
Just an observation. I understand that jammers are illegal for very good reasons, and their abuse can lead to much more harm than good.
It really isn't a matter of older vs. newer- older GPS receivers are probably more resistant to interference due to them having more extensive front end filtering- the newer modules just keep dropping stuff off to reduce size and cost. The fundamental issue is that GPS is a signal coming down from orbit! The closest a satellite ever gets to a receiver is about 8000 kilometers! Their effective radiated power is just about 500W (this is actual power * antenna gain)- it ends up that the signal at the ground is below the noise level and must be processed to bring it up to something usable.
MIPS released the R10000 core in 1995 which was their second superscalar design, and all subsequent MIPS designs have been based upon the R10000 core. Also, the M4K core that Microchip uses on the PIC32 has a 16 bit instruction word length mode (MIPS16e): http://www.mips.com/products/architectures/mips16e/ ARM's floating point is an extension to the architecture- the Cortex-A8 has a cut-down version that requires (according to the Wikipedia article) 10x more clock cycles per float operation. The utility of floating point for an embedded processor is somewhat questionable- It requires an awful lot of silicon for something that doesn't get used all that often (in embedded apps). The MIPS architecture does have floating point registers, though as I understand it, the floating point opcodes are more like macros.
I admit, I'm biased, but why do you view a MIPS core as a negative? It's just the core, and with the compilers available, 99% of the effort of switching between different manufacturer's parts (no matter what the core) is spent porting the peripherals. FYI, no compiler in Microchip's toolchain (8, 16, or 32 bit) has code size limitations.
The relevance of a PE is very highly industry dependent- I've been working as an electronics engineer for 21 years (Military R&D, Server Development, and Semiconductor Applications), and only worked with a PE once, and his PE was not necessary (or particularly relevant) for the work we were doing. It shows dedication, but doesn't really prove you can *do* anything.
Look at the people in your work environment that you respect and have advanced at a reasonable pace. If they have PEs, it might be a good idea for you to invest the effort.
Great for Tivo. Will they just partner up with DirecTV again? They had just about the perfect combination of DVR and service (Tivo DVR + directly recording the digital stream). Every other DVR I've used is a poor imitation. Tivo partnering up again has been teased about for years, but it all comes up to naught.
In my experience, the employers that really want Ph.Ds are educational and research institutions, and the odd technology company that wants to have some additional buzzwords to put on slides. It doesn't really add much for a technology company, unless your area of study is very specific to their business area. I'm kinda scared of any place that would do hiring based upon a degree or where it came from rather than what the person can actually do.
The financial system does contribute to society by proving risk-willing capital, that is why it was too big to fail.
Maybe I don't understand what "risk-willing" means, but isn't providing capital with risk associated with it have the built in assumption that it could fail? I always thought that part of what you have to pay for capital was also covering the risk should it actually fail. If my credit is poor, I end up paying a higher interest rate.
electric engines are up to 10 times smaller than ICE with the same horsepower, and they don't even need a transmission. if there is a problem with electric engines, it's the batteries.
10 times? Are you talking about engines in the power range of a motorcycle engine (50-100 bhp)? At the very rough conversion of 1KW to 1hp, Where do you get a 50KW motor you could put on a motorcycle? I'll take leaving out the battery/fuel tank comparison, but if you include everything else (including cooling and control circuitry) does the 10x size difference still hold?
Cheaper in the short term, absolutely, but the wages are being driven up. This isn't some secret stash of engineering talent known to only a few managers, the costs and wages will rise because of demand. In the longer term, because of the rising wages, the jobs will be shifted again- though it is a whole new generation and all the lessons have to be taught (and learned) again, making the cumulative costs higher than initially presented.
Moving jobs away works to reduce costs in the short term, but as a long term business strategy, there are flaws. If your business model is simply based on the "innovation" of lowering costs, your returns initially will be high, but not sustained.
I'm no economist, so I don't know the fundamental forces involved, but I have seen I've seen it happen in my career: engineering jobs were booming in Taiwan, and US engineers were training Taiwanese engineers (I still have the lucite award for training my Taiwanese counterpart), though people kept getting snatched away by competitors- it was unusual for one engineer to work at the same place for more than 9 months. But the rising wages made Taiwan less attractive, and many of the jobs moved to mainland China, with development in Taiwan dwindling.
There is a lot of engineering talent (and potential engineering talent) in the US. The problem is that companies aren't willing to pay for it! The MBA management style has made it very hard to have a long tern engineering career- the engineer is viewed as a commodity (why do you think it is called "human resources"?) that can be easily replaced by another unit in another location, across the country or across the world. Why give a raise to retain an engineer in a position when you can save money by shipping the job somewhere else? Many people who are smart and want to have an income that slightly outpaces inflation may start in engineering, but don't stick around.
Some manager gets a promotion for lowering (apparent) costs by outsourcing, and after they're gone, another gets stuck with fixing it. We are very good at training engineers in foreign countries how to do what we do well, and in that, we have managed to do is to shift the engineering talent overseas, where it also gets more expensive, negating the benefit.
I'm not sure where you get the "many thousands of times cheaper to license" - if that was so, companies like MIPS (which does have significant market presence) would be *HUGELY* more profitable.
I'm trying to make 2 points:
1) ARM is not open. It is licensable.
2) ARM is not magic. It does not enable you to do anything that you can't do on another core.
There are good compilers available for more than ARM- gcc has been ported to many different cores (ARM, SPARC, MIPS, x86 are just a few).
Foundries don't care about your core. They care about the individual transistors, I/O structures.
Power draw is a differentiator, but ARM, in terms of DMIPs/MHz, mA/MHz, or peak clock rate is not revolutionary- not the best, not the worst- the physics underlying the transistors is the same for everyone.
I/O pins are definitely not related to the core- The number and type is related to the implementation. ARM by itself, doesn't allow you direct access to the I/O pins.
Access to engineers is valuable- that is still about the license- an engineer costs a certain amount- that gets rolled into your license cost (or built into your per-core royalty) If you don't have a track record, your license is going to cost a lot more.
What I have seen is that ARM has a very good branding strategy, based upon the flawed perception of portability between different ARM cores (yes, the core ports, but that's a very small effort of the porting between manufacturers- the vast majority of your effort will be spent porting the peripherals, which are completely different manufacturer-manufacturer). It works out that the effort to port between the same ARM core from different manufacturers is about the same as porting from the ARM core part to a completely different core (they both end up requiring a lot of resources to complete).
Going back to the original point I was trying to make- ARM is not "open" in any sense of the word. You don't get the core unless you have a lot to invest, and we are a long, long way from from someone using their makerbot to whip up a new processor.
So something can't be "open" unless you can do it at home on the cheap? This argument is silly.
That is very much up to debate- but you'll find very few people who will call something with a $1.8M license fee open. No matter how you cut it, you are not going to be able to license the ARM core without giving something on the order of >$1M to ARM Holdings. And they won't give it to you on spec.Personally, if I'm charged anything more than a reasonable 'media fee' I don't consider it open. Would you call Windows "open" because it doesn't cost a lot to license?
The concept of 'open' is very much tied the spirit of 'open source.' ARM is nowhere near open source. From the Wikipedia article on Open Source: "A main principle and practice of open-source software development is peer production by bartering and collaboration, with the end-product, source-material, "blueprints," and documentation available at no cost to the public. " We can quibble about what 'no cost' truly means, since we do pay for our computers and our connection to the internet. According to: http://en.wikipedia.org/wiki/Comparison_of_CPU_architectures, the ARM code is 'unknown' under "open" and "no" under royalty free.
Going back to one of my previous posts- ARM isn't magic, and ARM and x86 aren't the only cores out there, let alone the only cores that can run Linux. Given a good kernel and a good compiler, the core doesn't matter.
HARDWARE DOES MATTER!!! I'll completely disagree with you here. ARM allows people to develop high-end systems on a chip that meet exact needs which is exactly why they are SOOO popular.
Hell yes, hardware does matter, but nothing makes ARM magic. Yes, it is very popular, but not because of anything inherent in the design. It is popular because of a lower cost (but hugely significant) cost to license. Please point out something that makes ARM unique and more enabling than other cores. There is a core in every single microprocessor. Do you know the type of core in every device you own? I sure don't. ARM has a remarkably good branding strategy, but there is absolutely *NOTHING* in what you actually do with a modern microprocessor that forces you to a single (core) architecture.
Going back to the original point I was trying to make- ARM is not "open" in any sense of the word. You don't get the core unless you have a lot to invest, and we are a long, long way from from someone using their makerbot to whip up a new processor. ARM has valuable IP- they don't hand their info to just anyone on the promise that "we're going to make lots of MONEY!" They want to see a return on their investment. If you're not going to make very many, you probably have to pay a higher licensing fee- and this is speculation here, but not going too far out on a limb, I'm guessing that the license+royalty fee still works out to something on the order of the (previously discussed) average.
As I haven't seen any, I'm pretty sure that any modern ARM core is complex and/or big enough to not fit in programmable logic- you've got to have at least an ASIC- being able to implement a core in programmable logic is vital for a true 'open source' core if we want to ever get out of the pure simulation phase. I'm not aware of any core that can run Linux out of programmable logic, though I would very much love to be shown one that does.
Going back to one of my previous posts- ARM isn't magic, and ARM and x86 aren't the only cores out there, let alone the only cores that can run Linux. Given a good kernel and a good compiler, the core doesn't matter.
I'm not even sure if AMD is really a 'licensee' of x86 since 1994 (intel canceled their agreement in 1986 and it was a legal battle until 1994)- as far as I am aware, AMD's current core is a 'clean room design' that owes no fees to Intel.
All the core does (by itself) is math/logic functions, conditionals, and move data around. *EVERYTHING* else is done by a peripheral. Embedded processors are (almost by definition) packed with peripherals. We get very used to these peripherals, but they're there, and if you want your computer to do anything other than serve as a way to deplete batteries, you've got to send data to/from a peripheral. Every different ARM variant has a different set of peripherals and different ways to use them- hence the fragmentation in the Linux kernel. There really isn't anything magic about ARM- the differentiation is mostly marketing.
I'm 100% certain that if ask ARM to license 10, 100 or even 1000 cores at $0.11 per core, they won't even talk to you. Developing a device around an ARM core is expensive and has high start-up costs. Remember that $1.8M is the average cost of a license, some people pay more, some less, but ARM holdings is a for-profit company, not a charity. They are out to make money. It is not in their business interests to license the core to you if they aren't going to make money off of it, and on average, they made $1.8M per license (in 2006).
There are? OpenCores has one beta VHDL implementation (it hasn't been updated since December 2009) that I can find with a quick search- everything else I find leads to a dead-end. I don't see any ARM cores listed on opencores that have been ASIC proven.
While there may be some designs available, I don't think any of the ARM implementations that are in the Linux kernel are based on an open core. If you are aware of an open core that can run Linux, I would appreciate a pointer.
Beyond anything else, ARM is a trademark used to refer to one of a bunch of cores that the ARM Holdings company have made. Saying you have an open ARM core is only scratching the surface of what the part actually does- for example the first ARM core (ARMv1) had no cache, no MMU, and ran (typically) at less than 2 DMIP- not something you'd really have a hope of running the Linux kernel on.
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Who cares about pi or tau? e shows a much more in depth understanding of mathematics.
I don't see it mentioned, so I must: "The Night We Buried Road Dog" by the late Jack Cady. It is a multiple award winning novel, but it seems that Jack Cady never really got big sales or other accolades during his lifetime.
Building a shielded room is a simple idea, but unattainable in practice. An effective Faraday cage is much, much, harder to build than just lining the walls with metal- in particular, the doors would need special seals, and any effect would be negated once you open a door. You need ventilation too, right? Wires to get power into the room...
NB: Grounding won't make a difference with respect to RF, particularly at the frequencies modern communication devices run.
A Faraday cage that big (and effective) is extraordinarily expensive. RF is very effective at making its way through tiny holes. It is even more difficult once you start including doors that open and close frequently. And your microwave's RF seal is not nearly as effective as you think.
My (3rd party observation, of course I wouldn't do this) is that the drivers look at their phone for a second and put the phone down. My supposition is that they realize that their conversation is not so important-- it can wait until they are no longer driving. Using a jammer is passive agressive to be sure, illegal in many jurisdictions, and can be very rude. The user of such a device must be prepared to accept the consequences. A better solution would be that people pay appropriate attention while driving.
In the United States, jammers are illegal for everyone.
I've seen the effect upon drivers talking on their phones while driving. While talking on the phone, their speed is erratic and inconsistent, they wander around their lane. Once in range of such a device, they look at their phone for a second or two, put the phone down, and start to pay attention to the machine that they are controlling. Once their conversation ends, they have become much more responsible drivers, aware of those that are sharing the road with them.
Just an observation. I understand that jammers are illegal for very good reasons, and their abuse can lead to much more harm than good.
Whoops, thought I was being smart by subtracting the earth's radius. My point stands- they're *really* far away.
It really isn't a matter of older vs. newer- older GPS receivers are probably more resistant to interference due to them having more extensive front end filtering- the newer modules just keep dropping stuff off to reduce size and cost. The fundamental issue is that GPS is a signal coming down from orbit! The closest a satellite ever gets to a receiver is about 8000 kilometers! Their effective radiated power is just about 500W (this is actual power * antenna gain)- it ends up that the signal at the ground is below the noise level and must be processed to bring it up to something usable.
MIPS released the R10000 core in 1995 which was their second superscalar design, and all subsequent MIPS designs have been based upon the R10000 core. Also, the M4K core that Microchip uses on the PIC32 has a 16 bit instruction word length mode (MIPS16e): http://www.mips.com/products/architectures/mips16e/ ARM's floating point is an extension to the architecture- the Cortex-A8 has a cut-down version that requires (according to the Wikipedia article) 10x more clock cycles per float operation. The utility of floating point for an embedded processor is somewhat questionable- It requires an awful lot of silicon for something that doesn't get used all that often (in embedded apps). The MIPS architecture does have floating point registers, though as I understand it, the floating point opcodes are more like macros.
I admit, I'm biased, but why do you view a MIPS core as a negative? It's just the core, and with the compilers available, 99% of the effort of switching between different manufacturer's parts (no matter what the core) is spent porting the peripherals. FYI, no compiler in Microchip's toolchain (8, 16, or 32 bit) has code size limitations.
The relevance of a PE is very highly industry dependent- I've been working as an electronics engineer for 21 years (Military R&D, Server Development, and Semiconductor Applications), and only worked with a PE once, and his PE was not necessary (or particularly relevant) for the work we were doing. It shows dedication, but doesn't really prove you can *do* anything. Look at the people in your work environment that you respect and have advanced at a reasonable pace. If they have PEs, it might be a good idea for you to invest the effort.
Yep, I did miss it. Not in my market yet anyway. I don't do the sharing with other devices in the house, and I'm willing to pay the premium.
Great for Tivo. Will they just partner up with DirecTV again? They had just about the perfect combination of DVR and service (Tivo DVR + directly recording the digital stream). Every other DVR I've used is a poor imitation. Tivo partnering up again has been teased about for years, but it all comes up to naught.
In my experience, the employers that really want Ph.Ds are educational and research institutions, and the odd technology company that wants to have some additional buzzwords to put on slides. It doesn't really add much for a technology company, unless your area of study is very specific to their business area. I'm kinda scared of any place that would do hiring based upon a degree or where it came from rather than what the person can actually do.
The financial system does contribute to society by proving risk-willing capital, that is why it was too big to fail.
Maybe I don't understand what "risk-willing" means, but isn't providing capital with risk associated with it have the built in assumption that it could fail? I always thought that part of what you have to pay for capital was also covering the risk should it actually fail. If my credit is poor, I end up paying a higher interest rate.
electric engines are up to 10 times smaller than ICE with the same horsepower, and they don't even need a transmission. if there is a problem with electric engines, it's the batteries.
10 times? Are you talking about engines in the power range of a motorcycle engine (50-100 bhp)? At the very rough conversion of 1KW to 1hp, Where do you get a 50KW motor you could put on a motorcycle? I'll take leaving out the battery/fuel tank comparison, but if you include everything else (including cooling and control circuitry) does the 10x size difference still hold?
Moving jobs away works to reduce costs in the short term, but as a long term business strategy, there are flaws. If your business model is simply based on the "innovation" of lowering costs, your returns initially will be high, but not sustained.
I'm no economist, so I don't know the fundamental forces involved, but I have seen I've seen it happen in my career: engineering jobs were booming in Taiwan, and US engineers were training Taiwanese engineers (I still have the lucite award for training my Taiwanese counterpart), though people kept getting snatched away by competitors- it was unusual for one engineer to work at the same place for more than 9 months. But the rising wages made Taiwan less attractive, and many of the jobs moved to mainland China, with development in Taiwan dwindling.
There is a lot of engineering talent (and potential engineering talent) in the US. The problem is that companies aren't willing to pay for it! The MBA management style has made it very hard to have a long tern engineering career- the engineer is viewed as a commodity (why do you think it is called "human resources"?) that can be easily replaced by another unit in another location, across the country or across the world. Why give a raise to retain an engineer in a position when you can save money by shipping the job somewhere else? Many people who are smart and want to have an income that slightly outpaces inflation may start in engineering, but don't stick around.
Some manager gets a promotion for lowering (apparent) costs by outsourcing, and after they're gone, another gets stuck with fixing it. We are very good at training engineers in foreign countries how to do what we do well, and in that, we have managed to do is to shift the engineering talent overseas, where it also gets more expensive, negating the benefit.
I'm trying to make 2 points:
1) ARM is not open. It is licensable.
2) ARM is not magic. It does not enable you to do anything that you can't do on another core.
There are good compilers available for more than ARM- gcc has been ported to many different cores (ARM, SPARC, MIPS, x86 are just a few).
Foundries don't care about your core. They care about the individual transistors, I/O structures.
Power draw is a differentiator, but ARM, in terms of DMIPs/MHz, mA/MHz, or peak clock rate is not revolutionary- not the best, not the worst- the physics underlying the transistors is the same for everyone.
I/O pins are definitely not related to the core- The number and type is related to the implementation. ARM by itself, doesn't allow you direct access to the I/O pins.
Access to engineers is valuable- that is still about the license- an engineer costs a certain amount- that gets rolled into your license cost (or built into your per-core royalty) If you don't have a track record, your license is going to cost a lot more.
What I have seen is that ARM has a very good branding strategy, based upon the flawed perception of portability between different ARM cores (yes, the core ports, but that's a very small effort of the porting between manufacturers- the vast majority of your effort will be spent porting the peripherals, which are completely different manufacturer-manufacturer). It works out that the effort to port between the same ARM core from different manufacturers is about the same as porting from the ARM core part to a completely different core (they both end up requiring a lot of resources to complete).
Going back to the original point I was trying to make- ARM is not "open" in any sense of the word. You don't get the core unless you have a lot to invest, and we are a long, long way from from someone using their makerbot to whip up a new processor.
So something can't be "open" unless you can do it at home on the cheap? This argument is silly.
That is very much up to debate- but you'll find very few people who will call something with a $1.8M license fee open. No matter how you cut it, you are not going to be able to license the ARM core without giving something on the order of >$1M to ARM Holdings. And they won't give it to you on spec.Personally, if I'm charged anything more than a reasonable 'media fee' I don't consider it open. Would you call Windows "open" because it doesn't cost a lot to license? The concept of 'open' is very much tied the spirit of 'open source.' ARM is nowhere near open source. From the Wikipedia article on Open Source: "A main principle and practice of open-source software development is peer production by bartering and collaboration, with the end-product, source-material, "blueprints," and documentation available at no cost to the public. " We can quibble about what 'no cost' truly means, since we do pay for our computers and our connection to the internet. According to: http://en.wikipedia.org/wiki/Comparison_of_CPU_architectures, the ARM code is 'unknown' under "open" and "no" under royalty free.
Going back to one of my previous posts- ARM isn't magic, and ARM and x86 aren't the only cores out there, let alone the only cores that can run Linux. Given a good kernel and a good compiler, the core doesn't matter.
HARDWARE DOES MATTER!!! I'll completely disagree with you here. ARM allows people to develop high-end systems on a chip that meet exact needs which is exactly why they are SOOO popular.
Hell yes, hardware does matter, but nothing makes ARM magic. Yes, it is very popular, but not because of anything inherent in the design. It is popular because of a lower cost (but hugely significant) cost to license. Please point out something that makes ARM unique and more enabling than other cores. There is a core in every single microprocessor. Do you know the type of core in every device you own? I sure don't. ARM has a remarkably good branding strategy, but there is absolutely *NOTHING* in what you actually do with a modern microprocessor that forces you to a single (core) architecture.
Going back to the original point I was trying to make- ARM is not "open" in any sense of the word. You don't get the core unless you have a lot to invest, and we are a long, long way from from someone using their makerbot to whip up a new processor. ARM has valuable IP- they don't hand their info to just anyone on the promise that "we're going to make lots of MONEY!" They want to see a return on their investment. If you're not going to make very many, you probably have to pay a higher licensing fee- and this is speculation here, but not going too far out on a limb, I'm guessing that the license+royalty fee still works out to something on the order of the (previously discussed) average.
As I haven't seen any, I'm pretty sure that any modern ARM core is complex and/or big enough to not fit in programmable logic- you've got to have at least an ASIC- being able to implement a core in programmable logic is vital for a true 'open source' core if we want to ever get out of the pure simulation phase. I'm not aware of any core that can run Linux out of programmable logic, though I would very much love to be shown one that does.
Going back to one of my previous posts- ARM isn't magic, and ARM and x86 aren't the only cores out there, let alone the only cores that can run Linux. Given a good kernel and a good compiler, the core doesn't matter.
I'm not even sure if AMD is really a 'licensee' of x86 since 1994 (intel canceled their agreement in 1986 and it was a legal battle until 1994)- as far as I am aware, AMD's current core is a 'clean room design' that owes no fees to Intel.
All the core does (by itself) is math/logic functions, conditionals, and move data around. *EVERYTHING* else is done by a peripheral. Embedded processors are (almost by definition) packed with peripherals. We get very used to these peripherals, but they're there, and if you want your computer to do anything other than serve as a way to deplete batteries, you've got to send data to/from a peripheral. Every different ARM variant has a different set of peripherals and different ways to use them- hence the fragmentation in the Linux kernel. There really isn't anything magic about ARM- the differentiation is mostly marketing.
I'm 100% certain that if ask ARM to license 10, 100 or even 1000 cores at $0.11 per core, they won't even talk to you. Developing a device around an ARM core is expensive and has high start-up costs. Remember that $1.8M is the average cost of a license, some people pay more, some less, but ARM holdings is a for-profit company, not a charity. They are out to make money. It is not in their business interests to license the core to you if they aren't going to make money off of it, and on average, they made $1.8M per license (in 2006).
While there may be some designs available, I don't think any of the ARM implementations that are in the Linux kernel are based on an open core. If you are aware of an open core that can run Linux, I would appreciate a pointer.
Beyond anything else, ARM is a trademark used to refer to one of a bunch of cores that the ARM Holdings company have made. Saying you have an open ARM core is only scratching the surface of what the part actually does- for example the first ARM core (ARMv1) had no cache, no MMU, and ran (typically) at less than 2 DMIP- not something you'd really have a hope of running the Linux kernel on.