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New ARM-powered chip aims for battery life measured in decades

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Re: New ARM-powered chip aims for battery life measured in decades

#71

Earlier quoted context omitted.

I'm trying to figure out if you're joking or not. BTU = British Thermal Unit and is pretty much the standard measure used around the world when talking about energy use associated with heating. It's the amount of energy needed to heat one pound of water by one degree Fahrenheit, regardless of where you find yourself in the world...

While only one data point, in Germany BTU is very uncommon. Energy used for heating is expressed as kWh, same as with electricity.

BTUs are used a lot in Canada, but Canada only made about 9 years of progress toward metrification between 1976 and 1985, I was still in high school when our Metric Commission was abolished along with most legal requirements to use metric units, while still retaining them.

Maybe it's generational (I'm GenX), so I'm not sure if all Canadians muddle through both systems as much as I do but I seem to live in a constant superposition state between Metric and Imperial, with little sense about which I'll use for any particular purpose.

I use Celsius for cooking and low temperatures, but Fahrenheit for body temperature and most room temperatures; kilometres for long distances but inches and feet for height and most short distances; pounds for body weight, but never ounces (for that I use grams), for cooking and large weights I seem to mostly use metric units. Volumes are almost exclusively metric, I suspect because we also went through a transition when gallons shrunk from Imperial (4.54609 litres) to US gallons (3.785 litres).

I envy European consistency when it comes to metric.

Re: New ARM-powered chip aims for battery life measured in decades

#72

meanwhile the latest and greatest 2015 device is an all-day wristwatch the weight of a pack of cards [1] (for the smaller Apple watch [2]) that in Apple's own "watch test" tells time for up to 48 days before dying --- whoops, no, I meant 48 hours [3] : >Testing conducted by Apple in March 2015 using preproduction Apple Watch and software paired with an iPhone using preproduction software with 5 time checks (4 seconds…

Sure, the Apple watch is fairly likely to be a ridiculous geegaw. It's also going to do a lot more than the mechanical watches you are comparing it to. If you just want to tell time, there is a wide market of solar watches: http://www.casio-intl.com/asia-mea/en/wat/standard/solar_pow... http://www.seiko-cleanenergy.com/watches/solar/ The Seiko tech runs for 6 months with no charging (left in total darkness).

Yup, I've had a Citizen eco-drive (solar powered watch) which has been going 10+ years.

It's an interesting model - there's some form of drive mechanism for the analog hands that let them move independently of the time. I.e. if you turn it to stopwatch mode, the hands will move to 12:00 and use the minute hand for marking minutes.

I've always wondered what kind of electronics are in there - and if they're even digital.

Re: New ARM-powered chip aims for battery life measured in decades

#73
post #64

Earlier quoted context omitted.

I don't think that is a fair comparison. The 386 was a true CISC design while the ARM2 was RISC. One of the major points of RISC was to reduce silicon complexity by using a less complex design (and shoving the complexity onto software). Intel could have built an equal or better chip than the ARM2 but they were worrying about servicing the already established market for x86. P.S. Is it even reasonable to compare MIPS…

Intel did in fact build a RISC chip contemporary with the 386/486: http://en.wikipedia.org/wiki/Intel_i860 It had great instruction throughput performance by the specs but lacked in real applications, thanks to the sufficiently smart compilers never coming to be.

The i860's theoretical throughput was achievable only in very special cases in tight floating point kernels. Most code couldn't possibly perform as well, no matter how smart the compiler.

Intel's sane RISC was the http://en.wikipedia.org/wiki/Intel_i960​, somewhat by accident.

Re: New ARM-powered chip aims for battery life measured in decades

#74
post #62

Earlier quoted context omitted.

Early drafts had the machines using human brains as CPUs, but the idea was killed by suits who thought it'd be too hard to understand. It would have made the whole premise of the movie make much more sense.

Dan Simmon's 'Hyperion' trilogy used this idea (before Matrix) and I seem to recall it being one of the less silly things in there. A book can afford to be less mass-market-friendly than a movie, obviously, but I think it did pretty well.

It was 4 books, not 3: _Hyperion_, _Fall of Hyperion_, _Endymion_, and _Rise of Endymion_.

The Technocore AIs of the book series were considerably more clever than the Matrix AIs, in that they were able to arrange their affairs such that the humans did not even realize the AI were using human brains as their processors. There was actually a human military objective to locate the Technocore's processing hardware, which I'm sure the AIs found amusing. Kwatz!

Re: New ARM-powered chip aims for battery life measured in decades

#75

Earlier quoted context omitted.

Been done - on ARM instruction sets, no less. http://en.wikipedia.org/wiki/AMULET_microprocessor

Also on Forth instruction sets: http://www.greenarraychips.com/home/documents/index.html#GA1...

Not trolling... is this still a going concern, shipping eval boards, etc? I saw this a couple of years ago, someone commented on HN, and then nothing. I liked the eval board specs and it seemed reasonably priced given the low volume (maybe a hard sell when STM is all but giving away kits).

Re: New ARM-powered chip aims for battery life measured in decades

#76
post #68

I see that it's 32-bit, is the year 2038 problem a significant concern for a device like this?

That is purely a software issue. Word size does not limit how big numbers computer can handle, it just implies how big numbers it can handle efficiently . Even lowly 8-bit computers/microcontrollers can do arbitrary precision/bignum math.

Depending on your definition of big.

Re: New ARM-powered chip aims for battery life measured in decades

#77

Earlier quoted context omitted.

In the original script the machines used fusion for power and human brains for extra processing power but that was cut because people thought audiences would find it too confusing.

This makes potentially way more sense... except when the machines by themselves are supposed to be super-smart. Well, fiction isn't perfect. But it's always better when it aims for more plausibility..

It's like having a neural net coprocessor.

Re: New ARM-powered chip aims for battery life measured in decades

#78

Now we only need batteries that don't self-discharge within decades.

Lithium thionyl chloride batteries can last 40 years, based on a self-discharge rate of 1% per year. They're used for things like sensors buried in concrete where it's a hassle to change the batteries.

Re: New ARM-powered chip aims for battery life measured in decades

#79
post #73
post #64

Earlier quoted context omitted.

Intel did in fact build a RISC chip contemporary with the 386/486: http://en.wikipedia.org/wiki/Intel_i860 It had great instruction throughput performance by the specs but lacked in real applications, thanks to the sufficiently smart compilers never coming to be.

The i860's theoretical throughput was achievable only in very special cases in tight floating point kernels. Most code couldn't possibly perform as well, no matter how smart the compiler. Intel's sane RISC was the http://en.wikipedia.org/wiki/Intel_i960​ , somewhat by accident.

And of course, by the time we got to the Pentium Pro - and more or less everything ever since - we ended up with a hybrid pipelined superscalar design which takes advantage of the legacy of support (and, compared to VLIW, tight instruction coding), but as part of the decode pipeline, translates that to RISC µops inside with microcode.

The Transmeta Crusoe was a particularly notable (if not particularly successful) case in point, which brought that layer a little more visibility than most, although in all honestly, was probably mostly well-known for having been Linus Torvalds' employer.

There never was a particularly bright line between RISC and CISC, and it's only gotten blurrier with the decades as the two paradigms stole good ideas from each other.

That's not to say there isn't the occasional throwback, sometimes for a good reason. I've got an adorable little slug of a 'transparent' microprocessor on my desk which I hope sees the light of day sometime (when it actually works, because I've bricked it - first time designer == way too many errata! :P) because it's got some fun ideas for trust, like the host being able to directly read (and verify) all the software it's running.

Re: New ARM-powered chip aims for battery life measured in decades

#80
post #71

Earlier quoted context omitted.

While only one data point, in Germany BTU is very uncommon. Energy used for heating is expressed as kWh, same as with electricity.

BTUs are used a lot in Canada, but Canada only made about 9 years of progress toward metrification between 1976 and 1985, I was still in high school when our Metric Commission was abolished along with most legal requirements to use metric units, while still retaining them. Maybe it's generational (I'm GenX), so I'm not sure if all Canadians muddle through both systems as much as I do but I seem to live in a constant…

Imperial is mostly for measurements related to the body, (temperature, height/length, weight), presumably due to the amount of people who grew up with it and it's ubiquity in the American media. Pretty much every other aspect of those measurements not related to the body are done in Metric (It's -10c out, my yogurt is 750g, and it's about 5km to the store). Most room temperatures are in Celsius, or have dual options, and those that aren't are typically because we heavily use American made thermostats due to our trade connections, or it's an older model. Almost everything else uses Metric except for small exceptions like Construction which is again due to long/common use and trading with America. Everything with scientists/doctors is Metric.
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