Friday, August 01, 2014

serial communication

SparkFun Electronics has an excellent tutorial on serial communication on their website.

Wikipedia also has a fairly extensive article on UARTs, the electronic components found at both ends of most serial connections and responsible for encapsulating the complexities of making them work reliably, presenting simplified interfaces to the processors to which they are connected.

Sunday, July 27, 2014

why interconnect technologies?

As just about anyone who knows me can tell you, I'm into robots. But what I'm into is way beyond anything I could build myself, given current resources.

Once you get beyond a minimal level of robotic complexity, you start seeing advantages to breaking out parts of the computational load, keeping them relatively local to the sensors and effectors they manage. This means distributed processors, which is fine, until you start trying to get them to talk to each other, at which point you'll discover that you've just become a pioneer, exploring poorly-charted territory.

It's not that there hasn't been any groundwork at all done, but there's nothing close to being a single, standard approach to solving this relatively straightforward problem.

Nor is that so surprising, because until recently there hasn't been much need to solve it, since most devices had only a single CPU, or, if more than one, then they were tightly integrated on the same circuit board, connected via address and data buses, and most of the exceptions have been enterprise servers, with multiple processor boards all plugged into a single backplane.

But the time is coming when, for many devices, the only convenient way to connect distributed computing resources together will be via flexible cables, because they will be mounted on surfaces that move, relative to each other, and separated by anywhere from a few centimeters to tens of meters. But they'll still need fast connection, both low latency and high data rates.

From what I've seen so far, RapidIO is the leading contender for this space.

say hello to RapidIO

This is one installment in a new theme here: component interconnect technologies.

Tuesday, June 24, 2014

why a scientific inquisition would fail

People distrust authority, and for good reason.

There are many examples, both historical and contemporary, of authority being abused for the advantage (whether personal or collective) of those in authority and/or belonging to the power base behind the authority, or for reasons relating to unquestioned dogma. This is true across the board, whether that authority is religious, political, economic, or even scientific in nature.

There are also many examples of upstart movements and theories, deserving of being smacked down, in each of these realms. Aside from the background of nonsense noise, this is a problem in that it can be very hard to differentiate between a quack and the next Einstein, and broad suppression of quackery risks 'throwing out the baby with the bathwater'.

But beyond that, suppression feeds people's suspicion regarding authority, which plays into the hands of the quacks.

To me this appears to be an irresolvable quandary, and that the best we can do is to insure that the public is as prepared as realistically possible to evaluate novel ideas for themselves, and to detect the whiff of quackery wherever it might turn up – even when it emanates from the halls of authority.

Friday, June 06, 2014

T-Square, 25 years later

Arguably, considering the ongoing confrontation off the coast of Vietnam, China has come a long way in 25 years, but not yet so far that they can allow this video to be viewed by their own people.

Tuesday, May 27, 2014

ARM, economies of scale, and maintaining options

There is a rumor going around that Apple is (again/still) considering switching to its own ARM-based CPUs in at least its lower-end Macs.

First, consider that platform independence was one of the primary touchstones in the development of OSX, and, from the beginning, Apple maintained parallel PowerPC and Intel builds, for something like five years before finally deciding to take the plunge, driven, in the end, by IBM's unwillingness to continue to invest in energy-efficient consumer versions of its POWER architecture, and Motorola's disinterest in what they viewed as a niche market and heavy investment (eventually leading to heavy losses) in Iridium.

Driven by the need for reasonable performance in a very low energy package, Apple has developed its own line of processors, based on ARM, which they've made and sold by the millions, packaged in iPhones, iPods, iPads, AppleTVs, and perhaps even Airport Extremes. Because it owns the designs, the marginal cost of each additional unit is very low, and it's likely that they can assemble a circuit board bearing four, six, or even eight of their own A-series chips for what a single Intel processor costs them.

That Apple would maintain a parallel build of OSX on ARM is practically a given. Of course they do, and would have been doing so from the moment they had ARM-based chips that were up to the task.

Does the existence of such a parallel build mean that a switch to ARM is imminent? No, but Intel had better watch out that they don't try to maintain profitability by hiking the prices of their processors even higher, because it's very possible that they've already passed the point where Apple could get better performance for less money by using several of their own processors in place of one Intel processor.

And, don't forget that Apple has been through such a transition twice before; it would (will?) be as seamless as possible.

Sunday, May 11, 2014

deeply encoding real-world knowledge and experience

Why code?

That might seem like a strange question for someone like myself to be asking, but it's an important one.

It has become clear to many educators that some facility with data structures, algorithms, and user interfaces has become an important aspect of literacy. While this is a welcome development, it is nevertheless important to ask "to what end?"

Is it necessary, or even desirable, for all of today's K-12 students to grow up to be programmers? Clearly not. Not only are there many other positions which will need to be filled, but, beyond relatively trivial examples, programming is a subtle craft requiring a concurrence of aptitude, attitude, and knowledge to achieve useful results, and most people who are not professional programmers, even if they know enough to put together working code, are, in most instances, better off leaving the coding to the professionals.

Nevertheless, early exposure can tune one's attitude, and improve one's aptitude and one's chances for accumulating the necessary knowledge. At least as importantly, it will also serve to identify those with a particular gift for coding sooner than would otherwise be the case. But there is value in that exposure that has very little to do with preparation for direct involvement in future programming projects, and a great deal to do with learning to think rationally and to communicate with precision.

Those skills are generally applicable, in all manner of vocations, for reasons having nothing to do with computing, but they become particularly important as decisions formerly made and tasks formerly performed by humans become the purview of machines, whether computers or robots.

For each such real-world context into which some degree of automation is to be introduced, it is vital that there be at least one person who is adept or able to interpret for those who are, and possesses the clarity of thought and expression to guide those who are tasked with developing those cybernetic systems. Without such guidance, in the vast majority of cases, automation also means a sacrifice of competence, as even senior engineers are rarely also domain experts, outside of their specialities, which may or may not apply to the project at hand.

By insisting that all students have some exposure to programming, we are improving the chances of such a person being available to guide the next expansion of the domain of automation, and the next, and the next, and thereby improve the chances that the knowledge and skills of contextual experts will be preserved in the process.

Tuesday, May 06, 2014

passengers demand to be paid for riding first class

Internet backbone provider Level 3 reports that six of the internet service providers it connects to have allowed those connections to remain continuously congested, and that these same ISPs are insisting that Level 3 should be paying them for access to their networks.

[Insert sound of loud, annoying buzzer.]

The problem with this is that it's backwards. If anyone should be paying for access to a network, it ought to be the companies with subscriber income paying the backbone providers, not the other way around.

Wake up and smell the stench of irrational overreaching, people!

Friday, May 02, 2014

if you could only attend one of the two?

The 2014 Apple Worldwide Developer Conference (WWDC) opens June 2nd, in San Francisco, at which the company is widely expected to have something more to say about its reportedly health-related 'iWatch' product. Arch-competitor Samsung just announced its own health-related event five days earlier, also in San Francisco.

I have to wonder just who Samsung thinks is going to attend their event. Local tech journalists with nothing better to do, obviously, but what if you were a tech journalist based somewhere further away than San Jose or Sacramento, and weren't already planning to spend the week leading up to WWDC seeing the sights of San Francisco, and had invitations to both events, but could only reasonably attend one of them, which one would you choose? For most, the choice would be obvious, and it wouldn't be Samsung.

We can presume the coverage of the Samsung event will come from 1) locals, 2) junior staffers sent by their editors, and perhaps 3) a vacationing pundit or two.

So why is Samsung going to the trouble when the most likely outcome is that their event will serve as a set, which merely lofts the ball for Apple's spike?

I see three ways in which Samsung stands to benefit.

If Apple makes no mention of anything resembling an 'iWatch' in the public keynote which opens WWDC, then, for a few weeks or months, Samsung looks like the company that's actually doing something about health, and gains a degree of credibility for being in the market from the beginning, when in fact they are very late entrants.

If, on the other hand, Apple does introduce the 'iWatch', Samsung's event will serve to focus even more attention on it than would have otherwise been the case, drumming up even more hype, and, presumably, expanding the size of the potential market for health-related devices in general, of which Samsung might reasonably expect to eventually inherit a sizable chunk.

However, the real coup for Samsung would be if the state of readiness of the 'iWatch' project is such that Apple would prefer to delay its announcement, but, having been thus challenged by Samsung, opt to go ahead with a pre-announcement, even though product availability is still months away, thus providing Samsung with both a clear target and time enough to pull off one of their rapid cloning acts.

Very clever, actually.

Wednesday, April 23, 2014

the departure of Apple's yes-men

Much has been made of the turnover at Apple since the death of Steve Jobs, with more than a few concluding that Apple's time of amazing success is over, to be replaced by either stagnation or decay. Steve was the source of innovation within the company, they argue, and without him Apple is doomed.

There's no doubt that Steve was a genius, in his own way, and that Apple's turnaround and rapid ascension to contend for the title of most valuable company in the world was, in no small part, his doing. On the other hand, as much as he relished being surrounded by brilliant minds who could steal the spotlight from him, there is a strong tendency for such powerful leaders to become encrusted with others for whom the truth is whatever the leader says it is, who contribute little more than amplification of that leader's insights and predilections.

No more. Those days are gone at Apple, or at least so dramatically altered as to require a wholesale changing of the guard. Tim Cook may not have Steve's charisma, but neither is he as susceptible to flattery, and, as long-time operations chief, he has a great deal of practice in peering through pretense to gauge whether a person, partner firm, or product proposal contributes to the company's health or degrades it.

Any who made a career of being a yes-man for Steve would have a very hard time of it in today's Apple, and I would like to suggest that underlies the departure of at least a few from the company.