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Update: Raspberry Pi-Compatible Development Board Cancelled

LoRdTAW Re: Broadcom... (165 comments)

As good as the BBB is, the layout sucks. My beef is the micro HDMI port is so close to the only USB port that thumb drives or fat USB plus interfere with the HDMI plug. If you have a previous gen BBB with the 2GB eMMC, the new Debian distro leaves you with 60 MB free space. The Angstrom distro is dead. So you have to boot from the SD card.

But the biggest benefit is the external memory bus for FPGA connectivity. But that disables the HDMI port as the ports are shared on the SoC.

I wish they would add more USB ports, move the HDMI port and if possible, move to an SoC that does not sacrifice the HDMI for the external memory bus. Overall it blows away the RPI.

2 days ago

States Allowing Medical Marijuana Have Fewer Painkiller Deaths

LoRdTAW Re:Congressional Pharmaceutical Complex (213 comments)

" There seems to be this attitude out there that pot is harmless, and that's just not the case in my experience. In moderation, it's probably safe. But chronic use- long term use at high doses- seems to really fuck people up."

Replace pot with Alcohol, cigarettes, HFC's, video games, etc. and its pretty much the same thing. How far can it swing in the other direction? You mentioned alcohol has bad long term effects. But despite this people still drink themselves to death, drive drunk and kill others or get killed, or become a raging ass holes causing mayhem. People still smoke cigarettes despite the exorbitant cost and adverse health effects including cancer. People still drink gallons of soda and sugar crap until their pancreas packs it in and shuts down. People play video games until they loose their jobs, wives, kids and home or in some cases, until they drop dead. There is nothing the government can do at that point other than prohibit it these things and we all know how that works out. It's either all with some restrictions (don't drive and you must be 18 years old).

The people have to be the ones to use judgement. If someone smokes so much weed and they fry their brains then that is their fault. Just like the old 65yo blue collar retiree who spends every night at the bar downing 6+ pints until his liver fails (know a guy who this just happened to. sad). People have to be educated and they have to be smart.

Oh and I can counter your burn out pot head story with an anecdote of my own: I have a friend who at one point worked two jobs and got a degree at the same time. I asked him how he did it his answer was "Copious amounts of marijuana bro." He smokes in the morning, on his way to work while at work and at home. He is very energetic, driven and lively. Quite the opposite of your theory. So it of course depends on the person.

I have also known people who smoked a lot and were fucked up because they were fucked up to begin with. You just always assumed they were messed up because of the pot but meanwhile you never really knew them well enough and they were messed up in the head to begin with. I worked with a kid who would go berserk is he didn't smoke and he smoked all the time. If he drank he was VIOLENT. A night out with him meant he was going to get into a fight and usually win because he was a hulk of a man. Turns out his father was exposed to chemical warfare agents while in nam and had a lot of mental issues including PTSD. His father ambushed him and his mother with a knife thinking they were Vietcong which promptly ended that marriage. He also had a very dysfunctional life and had a lot of really fucked up friends (I mean what friend tells you to fuck their own mother because she thinks your cute and lets you actually follow through? Yea, those were his friends. They gave me the heebie jeebies). The smoking was probably medicating him.

In the end legalizing it will create new problems but they will be far more petty than what we have today. We can rid ourselves of a large amount of violent crime, people in jail and money spent on ruining lives while fattening the wallets of war machine peddlers. I'd rather live in a world full of cheery burnouts than drug gangs chopping peoples heads off with box cutters and chain saws, prisons bursting at the seams with inmates who just become more angry and make plenty of angry new friends they can do business with once they get out and government paramilitary goons wielding surplus military hardware shooting first and asking questions later (oops! no drugs here. Sorry for shooting your dog and father, kids. Have a nice life!). Legalize it, please.

2 days ago

MIPS Tempts Hackers With Raspbery Pi-like Dev Board

LoRdTAW Re:no price? (88 comments)

It doesn't always have to boil down to price. This is the same argument over and over again from some maker/hacker types who want to turn platforms into religions.

The Raspberry Pi is a lackluster board with a crummy SoC and limited I/O and no FPU. Not to say that the Raspberry Pi is total crap, it does its intended job very well and there is a lot of community support. Plus where else can you buy a $35 board that runs Linux and X with HDMI USB and Audio?

But it falls flat in a few areas that is frustrating. First off it has *ONE* PWM output. Anyone looking to use this for motor control has to add an external PWM chip. Not a big deal but an annoying one. Next problem is there is the Ethernet is a USB-Ethernet chip on board, there is no hardware Ethernet NIC on the SoC which robs the CPU of cycles. Next up, and this is my gripe with many boards: no high speed interface. There is so much more these boards could do if we could attach an FPGA to them. Sure there is SPI but it simply isn't fast enough for certain things. The only board that can do this is the Beagle Bone which gives you an external bus interface but that disables the HDMI as the pins are shardes on the SoC. So its a trade off.

What I want to see in a dev board: dual core SoC w/FPU, 1GB RAM+, GPU, HDMI, SD card, SPI, I2C, 6-8 channels of 16 bit PWM, 8 channels of Analog 12bit-16bit, hardware 10/100 or gbit, 4xUSB host, *external bus interface not shared with I/O*. That's it. Just let me plug an FPGA daughter card that gives me the option to load bit files from the CPU and we are golden. Then we can do what ever crazy thing we want: more custom PWM (e.g. directly drive 3 phase bridges), quadrature encoders, faster ADC's, delta-sigma DAC's, high speed I/O, custom bus interfaces, etc. And make it cost $75. We are close to having a board like this, we just need the interest and the right SoC.

3 days ago

This 'SimCity 4' Region With 107 Million People Took Eight Months of Planning

LoRdTAW Grid city (103 comments)

Building using a grid layout never changes. Back when I first played sim city on the Super Nintendo, the strategy to build megalopolis (population 500k+) was building on a grid. You build using 3x3 clusters of R, C or I but left the center of the 3x3 open. Instead you put special buildings and police/fire buildings in the center of the 3x3. To reduce pollution you built rail instead of roads. Fun game for its time and a friend and I came close to a megalopolis on stock maps without beating the scenarios, alien invasion and getting the water free map. I think we had 480-490k people.

3 days ago

33 Months In Prison For Recording a Movie In a Theater

LoRdTAW Re: The real crime here (463 comments)

It's really torture. You are torturing a person for close to 3 years by locking them in a cage with violent criminals. I have heard jail stories from dudes who did time for various crimes. Bottom line: you don't ever want to be in jail, even for a day of you aren't street hardened and can't fight.

about two weeks ago

Wheel Damage Adding Up Quickly For Mars Rover Curiosity

LoRdTAW Re:Odd material selection (162 comments)

Plastics don't do very well in a vacuum like atmosphere full of radiation with wide temperature swings in the long term. Plus the low average surface temperature of -82F/-63C makes plastics less malleable and in many cases, brittle.

In the low atmosphere they can become brittle from outgassing and are susceptible to cracking and can simply shatter like glass. Nylon wire ties in a vacuum chamber simply fall apart after a few months. Though the 6 mbar (4.5 Torr) Atmospheric pressure of Mars isn't a hard vacuum, it is still 0.6% That of Earth's average sea level pressure.

Then you have radiation degrading the plastics which again makes them brittle. A friend worked on RHIC out in Brookhaven National Labs and since he was small and skinny he was tasked with changing out a lot of the sensor cables on the ring. The insulation simply disintegrated from radiation. There was nothing they could do about it save for bulky shielding which would have made servicing impossible.

In the end, metals are simply more suited to the task.

about two weeks ago

Munich Reverses Course, May Ditch Linux For Microsoft

LoRdTAW Re:Surprise? (579 comments)

You would be surprised but there are a lot of AutoCAD people coming out of schools who get heavily discounted student versions. Plus there are a bunch of smaller less known CAD programs out there. I happen to like Ashlar Vellum Graphite for 2D/3D drafting. It can be buggy but it is very easy to use for a CAD n00b.

Not to be a jerk but what does a PCB CAD program which is an EDA tool have to do with a 2D drafting or 3D solid modelling? Eagle is not used to design buildings or automobiles. It is a bad example.

about two weeks ago

Munich Reverses Course, May Ditch Linux For Microsoft

LoRdTAW Re:Surprise? (579 comments)

"Reading comprehension fail?"

Apparently the mods were also full of reading comprehension fail.

about two weeks ago

Robotic Suit Gives Shipyard Workers Super Strength

LoRdTAW Re:Only geeks... (125 comments)

Yup. I know that on Long Island in Suffolk counties town of Babylon anything with a footprint bigger than 10x10 feet is needs a concrete foundation. That concrete foundation is now a permanent structure which requires a permit and tax revaluation. So keep it small and you won't be bothered. That or live in NYC where most people don't give a damn and build whatever. Let the next homeowner worry who is probably a developer looking to knock it down and put in a 6 family with no parking anyway.

about a month ago

Planes Can Be Hacked Via Inflight Wi-fi, Says Researcher

LoRdTAW Re:No they cant. (151 comments)

Here here:
In theory, a hacker could use a plane's onboard WiFi signal or inflight entertainment system to hack into its avionics equipment, potentially disrupting or modifying satellite communications, which could interfere with the aircraft's navigation and safety systems, Santamarta said.

So it stands that there really isnt much of a threat here. Either the journalist is confused or purposefully crafted the article so as to imply that a hacker with a wifi device can disable a planes navigation system or do worse. My money is on the latter. The reason I say that is because the two systems are indeed separate and not connected. This is why a Cobham rep said a hacker would need physical access to the planes avionics system. They (Cobham) made that distinction but the author never makes that clear.

And I remember a similar article on /. a while back about an airline entertainment system being vulnerable. I thought it was jetblue but I can't find the article at the moment. It was the same "alarming" report that turned out to be a flaw in the TV or entertainment system. The worst was people couldn't watch TV on their 6+ hour flight.

about a month ago

Animal Behaviour Specialists Map Out the Social Networks of Cows

LoRdTAW Re:I object. (66 comments)

" and generally taste worse than beef does."

Small sample:

So the general consensus is either pork or veal. Properly prepared pork is very tasty but I would say that beef can beat it out depending on the cut. Especially the tender and fatty skirt steak, better than filet mignon IMHO. Diet, gender, age and lifestyle could also affect taste. Perhaps a young fit female vegan would be the tastiest while an overweight 50y/o male alcoholic smoker would taste awful.

about a month ago

Free Copy of the Sims 2 Contains SecuROM

LoRdTAW Re:Anybody know? (234 comments)

I remember when Crysis came out it was secured with SuckROM. The idea was you inserted the DVD and SuckROM would verify the DVD was in the drive and the game would start, most of the time.

During the process of running crysis.exe securom would start and your mouse cursor would have this colorful CD icon attached to it. If securom failed to work properly (crash) which was every 1 in 3 or 4 times, the mouse cursor would stay a disco ball looking CD and your CD/DVD drive was rendered inoperable. A reboot was the only solution to solving it.

After a week of that I downloaded a cracked exe for a game I legally bought with my hard earned cash. And you wonder why the consumer hates DRM. That is part of the reason intrusive, rootkit like DRM needs to die in a fire.

about a month ago

What percentage of your media consumption is streamed?

LoRdTAW Re:Even my DVDs are streamed (152 comments)

I think the GP was saying that instead of ripping the DVD themselves, they save time and download a ripped copy. So they have a license for the media in the form of the purchased DVD. They just let someone else do the work for them. That should constitute fair use of the media.

From your post it appears that the ripped copy is considered a reproduction and needs a new license. Or am I confused?

about a month ago

Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

LoRdTAW Re:Hipsterism at its finest (worst?) (288 comments)

I too thought Apple was "buying" clean energy. But it turns out they have actually built a solar plant at their datacenter along with fuel cell backups.

This article peaked my interest though:

How exactly do they measure energy consumption from a particular power source? If the data center is grid connected the current will flow based on path of least resistance, loads and other factors. How can they be sure a load used 20% coal 30% nuclear and 50% natural gas? Did this information come from the power companies who can estimate the demands and current flows based on grid load? I read the linked Greenpeace report and nothing was made clear about how this was done.

about a month ago

Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

LoRdTAW Re:Apple no saint with 2 year disposable iPads (288 comments)

Oh come on. By the time the battery is half dead it will be replaced by the latest iPad lest the user be seen with last years model in public. Oh the shame that would bring them.

about a month ago

Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

LoRdTAW Re:Hipsterism at its finest (worst?) (288 comments)

2. Obviously you "know nothing, John Snow...." I've never had a SD card break, let alone stop working. My biggest fear with the MicroSD cards is that I will lose them, they are so tiny... So far so good...

Oh thank god. All this time I was thinking that no storage device is 100% reliable and here you come along and shatter that view. Thank you David_Hart for assuring me that SD cards are 100% reliable and never experience data loss. I am switching to SD cards for all of my backups from now on; both at home and at work! I am sure my boss will love how much money I saved him by switching from costly tape and off site providers to simple SD cards. THANK YOU!

about a month ago

Western US States Using Up Ground Water At an Alarming Rate

LoRdTAW Re:Why I'm on a well in a sustainable aquifer. (377 comments)

Also forgot to add that some aquifers consist of caverns that were formed from acidic water slowly eating away at the rock. These are stable until they are depleted which allows more water to migrate into them enlarging the cavity until it collapses. So not so much tunnels but natural caverns.

about a month ago

Western US States Using Up Ground Water At an Alarming Rate

LoRdTAW Re:Why I'm on a well in a sustainable aquifer. (377 comments)

When the underground maze of tunnels is filled with water the land above is stable.

There aren't any caverns or tunnels full of water. Aquifers are composed of sand gravel and other particles mixed with water. When that water is removed, a void begins to form as the space the water once occupied is now empty. The void can grow to an open cavern with no roof support as it is all sand and gravel. Once the roof collapses, the effect cascades until it reaches the surface which might be a hundred meters or more. That is how a sinkhole forms.

Ah, the special tang of a fermented corpse in the water fountain makes a trip to Orlando so interesting and it hasn't harmed Mickey Mouse one bit.

I've drank the water in Orlando and believe me, the flavor and odor the corpse would impart would be an improvement.

about a month ago

Google Offers a Million Bucks For a Better Inverter

LoRdTAW Re:110 or 240v (260 comments)

"And unless you really need 3-phase, split phase is easier to deal with - with 3-phase you need to monitor all three phases to ensure they are working (failure of one phase is a common failure mode that requires immediate shutdown of the other two phases lest any dangerous currents develop)."

Losing a phase will not result in dangerous currents in the supply system. The most common three phase load is a motor. If you start a three phase motor and remove one of the phases the motor will continue to run on a single phase BUT it will try to draw more current to compensate for the loss of the phase. You now have overloaded windings and the motor will quickly burn itself out. You use phase protection relays on your motors to open the contactor when a phase loss is detected. So you only need to protect your motors.

A DC power supply that runs on three phase won't be affected much but the bridge rectifier can be overloaded and output ripple will increase. It will also attempt to pull more current through the remaining phase and blow a fuse or breaker. So again, its only dangerous to the load. If a 3 phase heater loses a phase, then guess what? You get less heat. That's it. Resistive heater loads can tolerate a phase loss with zero electrical problems. Your process will be affected but thats about it.

A three phase alternator does not care what the load balance on any of its phases is as long as they aren't overloaded. Same goes for a transformer. Many homes are ran off of a three phase 120/208 Y (sometimes spelled wye). Homes still get single phase 120/208 but are connected to the supply (phases A, B, C and Neutral) as follows:

The split is repeated for homes and they balance out the grid nicely. Splitting each of the three high voltage legs from a feeder into a neighborhood and stepping it down using center tapped 120/240 transformers makes balancing a problem. You can't interconnect any of the three separate 120/240 lines as the neutral or center taps must be grounded. Now you have 3 sets of 3 wires to deal with and you have to ensure you even distribute loads across three separate 120/240 supplies. Are you going to run 7-9 wires down a block to balance out that mess? No, of course not. So now you have individual blocks of 120/240 which may be unevenly loaded. Three phase is much easier as three houses in a row can easily balance out a 3 phase feeder. Both systems are used in residential neighborhoods (and at random might I add) but anything new is always three phase fed.

My home in Queens NY is serviced by a 120/240 center tapped 100kVA transformer that feeds only our street from corner to corner. The neutral connects to the other poles but everyone else in the surrounding area is on three phase. The poles do have 2400/4160 three phase feeders on top so getting three phase is not an issue. How we became a 120/240 island is beyond me but it might have been a leftover from old practices, never upgraded or left alone for a specific reason. Out on long island the neighborhood I lived in for a short while has 120/240 and only a single high voltage leg running along the pole. So they have to balance out the load on the feeder side.

about a month ago

MIT Combines Carbon Foam and Graphite Flakes For Efficient Solar Steam Generati

LoRdTAW Re:But (110 comments)

I would worry more about condensation of the cool steam in the turbine itself. The only way this would be good for a turbine is if the steam can be further heated via a solar super heater.

This is why power plant boilers have a superheater which passes the steam from the boilers steam drum through a heat exchanger in the hot exhaust stream of the boiler. This brings the steam temperature up well past the boiling point of water and prevents steam from condensing in the turbine. Imagine a turbine spinning at 3600 RPM (for a 2 pole 60Hz alternator) in which droplets of water form and begin to collide with the blades. All you need is one blade to fail from getting pummeled with water and it's game over for the turbine. The steam is condensed once it exits the turbine exhaust which creates a vacuum effect which increases the turbines efficiency, you pull steam through it. The steam is condensed using cooling towers, water cooled heat exchangers or fed to a district heating system and customers pay to do some of the condensing (and maintain the infrastructure while increasing efficiency).

about a month and a half ago



Linux embedded system needed for a project

LoRdTAW LoRdTAW writes  |  more than 5 years ago

LoRdTAW writes "I am in the process of designing a custom heating control system for my home. Its an older house with steam heat and the heating is very uneven and I believe wasting allot of energy. Instead of spending upward of 30,000 dollars to upgrade (and ripping the house apart) I want to create a system to help me make my house more energy efficient and give me something to brag about. I am a Linux guy and I want a low power Linux powered x86 system with vendor expandable I/O options (Digital I/O, analog I/O, key pad, LCD, 1 wire etc.), removable flash storage (SD/CF) and RS232 / Ethernet interface for PC connection. The hardware needs to be easy for me to work with, I don't want to have to re-invent the wheel trying to get digital/analog I/O and external communications working together. An all in one development kit that includes the hardware, compiler and vendor I/O modules is a must. The local storage is important because I don't want to dedicate a power hungry PC for logging, it must be stored locally and remotely accessible for analysis when needed. Thermostat units are going to be built with the help of my friend who is experienced with PIC micro and the 1 wire bus. As for programming language, C is preferred but any language will do as long as it is flexible enough for my needs. The interface is going to be a small character or graphical lcd with a button pad and some led's."


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