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Comment HDL (Score 1) 165

Tl;DR [yet], but initially this sounds a lot like HDL's like Verilog and VHDL. The two fundamental constructs there are things that happen continuously (collections of simple logic gates) and things that happen based on a clock (registers, built around flip-flops). At a high level, this sounds like A = B+C is a continuous adder, and A is changed instantaneously with B and C. In the HDL world, this gets "compiled" down to silicon, but in a software world this would be radically harder to do, because you have to notify anybody listening to A that B and/or C has changed. Yes, it's like a spreadsheet in that sense.

Comment Re:Skyjack only works for WiFi drones! (Score 1) 161

I *highly* doubt the Amazon drones will be operated by some hobbyist Futaba or Spektrum protocol. Doing such a thing would be absolutely ludicrous from just about every angle possible. First of all, such protocols are nothing more than "stream-of-servo" positioning commands, and very badly suited to autonomous drone control. Honestly they're pretty badly suited to manual drone control IMO. Second, they are even less secure than WiFi. I'm going to take a wild guess and say that the Amazon drones will be cellular-controlled, with high-end SSL used to send the drone a set of GPS coordinates (waypoints, etc.), and the drone will handle *every* control aspect from there on out, as it should.

Comment Re:My lab (Score 1) 215

Marvin the domestic shorthair (humane society acquisition). His younger "sister" Kaylee was probably curled up on our bed at the time, plotting sneak attacks on Marvin in her sleep...

The mess is a consequence of the ongoing debugging of the primary project being interrupted by a bug that crept into a previous product and took over my desk with various levels of fix development for that. I'm cleaning up right now because the primary project may have just had a breakthrough and I need space to test it in full scale.

Comment My lab (Score 2) 215

First of all what I'm doing: I'm designing industrial embedded hardware, using funky data busses and high-resolution ADC's. I do all the hardware design, layout, prototype fabrication, and *all* firmware and host-side software. I'm pretty much a one-stop shop for this project (and the only engineer on it...). The hardware is all "slow" stuff at this point, with the fastest clock being the 32MHz driving the 8-bit microcontrollers scattered throughout the system.

Panorama of my office

First off I've got my computer in the "middle", nothing special except the monitor's on an arm to free up desk space. A second monitor to the right is used for debugging consoles etc. (and WoW). Several USB hubs are scattered around (some mounted) for use by both tools and the product under development.

To my left up on a shelf I have a (rented...) Agilent MSO-X 3014A scope, 4-channels plus 16 digital, unfortunately only the 100MHz version. I have a second-hand cheapy 5MHz signal generator next to that for occasional use (impedance checking etc). A simple Protek 3006B power supply (Fry's?) handles everything I can't run off USB 5V or from an LDO.

A Saleae Logic and Logic16 do quite a bit of work for me, and there's the occasional use of a BusPirate. An AVR-ISP MkII handles direct programming of the microcontrollers when possible, while the vast majority of my programming and test jigs are built around my own STK500v2 implementation multiplexed with serial debug.

To my immediate left is the main project space, while to my right is space for whatever projects crop up and don't have to have direct access to the scope.

In the window against the desk would be one or both cats.

To the far left is my soldering environment, which includes a regular temp-controlled soldering iron as well as an Aoyue Int968 hot-air soldering station (with its own soldering iron). A $25 toaster oven is used for reflowing most simple boards. Bins of loose parts cover the shelving above.

Behind me is a desk that holds a "proper" reflow oven, albeit the cheapo $300 unit from eBay, as well as a rework station of the kind used for XBox repairs (some of my boards have a *lot* of thermal mass that hot air alone can't handle). Reels upon reels of SMT parts are piled under the desk...

Lighting is provided by 2x 60/meter LED strips that side-fire to each side along the camera-window axis, plus an overhead Ikea quint-MR12 set over the main workspace when needed.

Comment Not exactly a new concept (Score 4, Interesting) 199

I've got a novel by John Brunner written in 1982 called The Crucible of Time (), which documents a (very non-human) species through its scientific awakening. Throughout the book they're discovering that their planet is getting closer to a cloud of debris dense enough to massively devastate the surface, possibly shatter the planet. In the end they manage to build enough arks to save the species. The foreward reads:

"It is becoming more and more widely accepted that the Ice Ages coincide with the passage of the Solar System through the spiral arms of our galaxy. ..."

Comment Re:4 years ago (Score 1) 410

Actually DVDs contain on anywhere from 4GiB to 9+GiB of mainline video... The whole reason for dual-layer discs was to get around the limitations imposed by the ~4.5GiB max of a single layer. The "base" read rate of a DVD (1x) is 1.32MiB/sec, which puts a 2-hour movie at peak bandwidth (hopefully because they actually maximized video quality rather than just being lazy with the encode) at 9.5GiB, just under the absolute max. Account for menus, special features, and average encoding levels, let's go with 6GiB.

OTOH, 2mph is rather low, with one source (http://answers.yahoo.com/question/index?qid=1005112200029) claiming studies put the average healthy male at 3.4mph. I'd also estimate there to be maybe a 50% functional walking time (eating, blisters, etc.).

And as others pointed out, on a serial line there are actually *10* transmitted symbols in a byte because of the start and stop framing. 11 or 12 if you add a parity bit and double-stop, but let's stick with 10.

"Furthest" redbox would likely be something like from Portland Maine to Los Angeles for example, which google puts at about 3100 miles.

3100mi / 3.4mph = ~911.75hr / 50% *roundtrip = 3647hrs
6GiB * 10bits/byte = 6442450944 symbols
6442450944 sym / 3647hrs = 490.69 baud

If one were to drive, as per Google it'd take ~46hrs with traffic, and if you trade off drivers. For that roundtrip I get about 19452 baud. Let's say 19.2Kbaud to leave time for chinese fire drills.

Comment Stuck?? (Score 5, Insightful) 366

I just totaled up the net "worth" of the top 25 people on Forbes 2013 billionaires list, and I got $839.8 billion. Not quite sure how $828.11bn is out of reach if certain people were sufficiently motivated, when it only takes the top 25. Now, if we were talking about something that cost $10 trillion or so, then I might consider it functionally out of reach, as that probably surpasses the net worth of the top several thousand.

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