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Comment Re:Why? (Score 2) 91

A 72mhz ARMv6 from STmicro

Why do you keep bringing up ARMv6? ARMv6 is a CPU architecture and uses complex caches, TLB units and a virtual MMU. I don't know of anyone trying to use these for flight controllers. The Cortex-M architecture, which is the basis for all of the common ARM based flight controllers (OpenFlight, BrainFPV, Naze, etc.), is not ARMv6. I don't think you understand what you're talking about.

Floating point isn't actually a good thing in flight controllers, fixed point is preferred..

PID controllers using floating point are available now in Cleanflight. Read about them here. Other code bases, such as BrainFPV and OpenFlight use the floating point units as well. Fixed point is preferred only by fanbois using MCUs without floating point units.

Super scalers make execution timing unpredictable

No, they don't. Out-of-order pipelines and elaborate branch predictors do that. Cortex MCU pipeline is in-order and the branch predictor is designed by ARM to be conservative and not cause lengthy pipeline stalls so the Cortex line remains suitable for real-time MCU applications. The timing characteristics of every instruction in every mode of Cortex devices is well known. This `problem' of unpredictable timing with ARM MCUs is a fiction inside your head.

Comment Re:Why? (Score 2) 91

Fanboi much?

The most popular flight controller around is the Naze32 with an STM32F1 ARM MCU. No one is having trouble with the instruction set, durability or any of that other stuff you're wrapped yourself around.

Cutting edge flight controllers have moved on to ARM Cortex-M4s. That MCU provides a floating point unit for faster signal processing of gyro and accelerometer data, implementing filters and solving PID calculations at much higher speed. Cortex-M7 is a thing now; six-stage, in-order, dual-issue superscalar pipeline with single and multiple double-precision floating point units in the same package and the same power consumption has the older parts. That's the future of flight controllers.

Comment Re:EPA and other like agencies have to know (Score 1) 414

So it's the government's fault.

I saw something yesterday in the House hearing I've never seen before in thousands of hours watching congressional testimony. The EPA explicitly declined to blame their budget for their failure to detect this. Their failure here is that undeniable.

The regulators own some of this. You can keep your hate filled little head buried in the sand about it if you want, but that won't change reality.

We fund these people with billions every year and they piss it away on lawyers pushing activist political agendas while the actual environment is ignored. And haters like you apologize for them.

Comment Re:Cycle beating. (Score 2) 414

One of the worse effects of all of this are the cultural consequences inside these corporations; your willingness to defeat the testing regime determines your fate. You can be certain the managers in charge today are the guys that "got it done" years ago by beating the tests. They're the ones that keep quiet, look the other way every time, and quietly make sure the honest ones don't get anywhere near responsible positions.

Comment Re:Forfeit all revenues from sales (Score 1) 414

I've also read in the last day or two that VW is (predictiably) trying to claim that management knew nothing about the emissions and that "a handful" of engineers were responsible.

This is true; VW is trying to isolate this to "a few software engineers." The most poignant moment in yesterday's testimony before the House was from Rep Chris Collins (R-NY); he pointed out that VW is not merely a car manufacturer, but also a major IP concern. VW, like the other major auto manufacturers, has teams of IP lawyers that analyze every aspect of their engineering and file for patents on every `innovation.' Yet somehow, after the inevitable struggle they must have had achieving the necessary power, mileage and emissions figures that no other diesel passenger car in the world could achieve without a urea injection system, they filed no patents on these amazing breakthroughs.

It's not a couple of software engineers, but proving that will be impossible; everyone that didn't have their name on the version control commits will claim they knew nothing, and the software engineers will claim they don't know how their `defeat device' ended up in production cars.

It's possible to get to the truth. It wouldn't even be that difficult; just arrest some engineers and file criminal charges. At some point one of them would cut a deal and talk. That won't happen, however. The Powers That Be are too busy getting their sons and daughters appointed to executive positions in these big companies, or negotiating huge `contributions' to the `non-profit' operations run by their various family members, so there won't be any perp walks of lowly programmers; our elite doesn't really want to be involved in kicking over these rocks.

Comment Re:Radios? (Score 1) 241


Piffle. Satellite phones can be had for less than $300 on Amazon. Mars explorers would be walking around in multi-million dollar suits filled with pumps, heaters and cameras all sucking on monster batteries. The cost of a transponder, in both money and power, would be lost in the noise. And that's just the suit radios; the giant rover would have multiple radios as well.

Face it. It doesn't make any sense. There are only two possibilities; the author is ignorant, or the author assumed ignorant readers.

Comment Radios? (Score 2) 241

Watched it last night. Didn't read the book.

How in the name of all stupid plot devices does each and every space suit, vehicle, structure and other large chunk of habitat equipment not have its own, independent up-link to the multiple Earth-Mars radio relays we already have in orbit around that planet? I squirmed for the first hour because that was too much disbelief to suspend; over the years as habitat equipment appeared on the surface prior to habitation a big collection of radio equipment would unavoidably accrete; they'd be tripping over redundant radio gear.

Maybe the book has some rationale for the mystifying lack of otherwise ubiquitous radio equipment and we can pin it on bad movie making. If the book tries the "lack of funding" trope I'll laugh; so the habitat isn't monitored because Republicans or whatever, yet NASA instantly picks up a signal some (now) ancient lander? Pfft.

Comment Answer? (Score 4, Interesting) 278

Proponents will also have to answer

You can give China MFN status one day in the name of "human rights" theater and then lecture Americans about the importance of environmental protection the next, and no one anywhere blinks an eye. Exactly when are proponents going to have to answer to anyone, about anything? Elites have been trading US prosperity for various and sundry bad overseas agendas since forever and none of them have ever paid the least price.

Comment Re:700 ms latency, though... (Score 2) 58

The latency is bad, but not that bad. Earth to geostationary and back round trip is about 250ms. Switching hardware and ground relay adds a few tens of milliseconds more, so typically you're well above 250ms but not usually more than 300ms. 700ms is some other problem; congestion or something.

But yes, the long round trip makes these systems unsuitable for low latency applications; certainly real time gaming is impossible, but also even just voice communication becomes awkward with that much delay. Some popular online games can be played with high latency; I know of EVE players that play successfully over satellite. That game only updates clients about four times a second at best.... so another quarter second of lag isn't that big a deal.

If your alternative is living in the dark then tens of megabits of high-latency bandwidth is pretty damn appealing.

Comment Re: None of my cards have a chip! (Score 0) 317

You asked someone employed at 7-Eleven a question about financial transactions and company policy and you believed them?



I'll take credible information reported by verifiable sources over your human debris anecdotes. As for my own anecdotes, I've used a chip reader at three retailers in the past week and had no trouble at all. There were no double charges, confusion or failures. The grownups already have this deployed, trained their staff and tested their systems. It's done. The laggards will cut over after they start eating the cost of the fraud they're helping to perpetrate.

And stop talking to convenience store clerks FFS. Do that often enough and one of them will give you a case of TB.

Comment Me too (Score 1, Redundant) 128

I've looked at some expensive KVMs, software control of display inputs and other stuff. Bottom line is no, there isn't a good solution of this. There are a bunch of limited, glitch-prone things you can do, but what you're thinking of doesn't exist yet.

My expectations for such a system are as follows; connect an number or computers (3-4 minimum) in arbitrary ways to a number of displays (4, minimum) and a set of input devices, without a.) lag b.) glitches c.) limitations on resolution, refresh, etc. Lag can be no more than a few imperceptible microseconds. Glitches include input devices not being recognized, causing hosts to have driver conniptions when switching, displays not getting signals, and other typical KVM behavior. All of this must happen using a single button press to switch among programmable configurations, and configuration done with a high quality native GUI on whatever platforms I happen to be running. Oh, and audio.

Modern displays usually have multiple inputs, and some of them even have non-shit firmware that switches between inputs quickly and without a bunch of mode-setting drama. The problem is there isn't a good, universal way to control this from software. There are some creepy, half-supported utilities floating around in freeware/shareware land that work with some displays. Barring that the current state-of-the-art is wearing out the input select button on a display you may not be able to reach...........

I wouldn't hold your breath either. Its going to take a few more years before it dawns on manufacturers that the desktop market hasn't actually died. Right now they're in table/laptop/phone mode and — aside from g-sync and other gamer stuff — there isn't much innovation going on with desktop hardware.

If you're willing to be very selective about your hardware and spend some money, particularly on your displays, you can almost get there. You'll need an active USB KVM system like ConnectPro, displays with a generous number of software controllable inputs, and you'll need to be to be prepared to deal with all the sundry glitches your creation with make you suffer.

Comment Re:How long will the company stay up? (Score 1) 494

This. Either regulations mean something or it's just a bunch of lawyers masturbating.

Every sale prevented by the destruction of VW will go to manufacturers that didn't willfully scam their customers, dealers and compromise public health. There are a plethora of car companies and brands that will be happy to grab up VWs market share.

Comment Re:How long will the company stay up? (Score 0) 494

The big difference is that GM's issue was purely safety related; their crimes didn't offend the Green Police. I'm certain the bulk of EPA staff figure GM's victims deserved what they got for commuting in a car instead of a bicycle. In any case you can certain the penalties will be far, far greater for VW et al. So I have to agree with the GP; VW is in jeopardy, at least in the US.

By the way, if you're one of the many, many VW TDI braggarts that have plagued every automotive discussion on Slashdot since forever; please dispose of your atmosphere wrecking pollution machine. Thanks so much!

Comment Re:Instrumenting c++ to behave like Rust (Score 4, Informative) 262

I found Rust

I've found it best not to talk about Rust around here. The language has already accumulated a legion of haters at Slashdot. Rational discussion about Rust sans the office punklets happens at Hacker News.

It was anticipated that Rust would motivate some progress in C++ memory safety. Some have argued that if that is all that Rust accomplishes it is worthwhile. Too bad an entire language has to be invented to get some folks off the dime.

The uptake of Rust is so large though I don't think it's going to go away just because C++ adopts some degree of compile time memory safety. The language is great on it's own merits, there is none of that half century of baggage to slog through and the entire stack and all native Rust third part modules provide the same memory safety guarantees, barring 'unsafe.'

These things, combined with the never ending stream of opportunities the segfaults and overflows that C/C++ cannot avoid providing will ensure a chunk of mind-share, haters be damned.

COMPASS [for the CDC-6000 series] is the sort of assembler one expects from a corporation whose president codes in octal. -- J.N. Gray