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Comment: Re:We aready have this (Score 1) 33

by PurpleAlien (#49377733) Attached to: Hand-Drawn and Inkjet Printed Circuits for the Masses (Video)
Over here in Europe we have http://www.eurocircuits.com/ You can get prototypes of your board in single digit quantity for very little money ( 100Euro easily). Seven days later, you have your boards in the mail. No issues with double sided boards, or even multilayer. They also take Eagle files directly, so no need to generate Gerber files etc. In addition, their web interface allows you to visually inspect your boards to make sure all the design rules are correct, and this also helps getting to a lower class of complexity of the PCB and lower your cost even further.

Comment: Re:I am an embedded developer - just do both (Score 1) 323

It is memory, registers and ports, e.g. BSF STATUS,5 would mean set bit 5 in the STATUS register. The reason why it is called 'File' is for historical reasons from terminology such as the 'register file'. This is apparent in other instructions such as FSR (File Select Register). The 'register file' is an array of the processor registers.

Comment: Re:keeping station behind it? (Score 3, Informative) 126

by PurpleAlien (#48915549) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble
The unit for acceleration is m/s^2. In this case, 'g' is used as a unit to distinguish acceleration due to free-fall (gravitational) from general acceleration (and is usually measured with an accelerometer). The unit is defined as 1g == 9.80665m/s^2. This unit definition does not change with location - on the moon it is around 0.18g.

Comment: Re:3G is terrible for all these things (Score 2) 118

by PurpleAlien (#48016009) Attached to: World's Smallest 3G Module Will Connect Everything To the Internet
Not just that, but IF you would want to use a cell network (for example aggregation in a network that works with 802.15.4 otherwise), why not just bog standard GPRS. Much better coverage than even 3G, and would still be fast enough. If the Telco's would be smart, they would even target SMS for this. Lower power consumption, even better coverage, and SMS revenue is in decline because everyone is using data to send text messages instead of actually using SMS. Telco's could provide bulk messaging for M2M applications... Instead, they won't because they are shortsighted - just like they wouldn't with the pager network.

Comment: Re:There is no "almost impossible" (Score 5, Informative) 236

by PurpleAlien (#47941873) Attached to: Apple's "Warrant Canary" Has Died
Actually, it is not. In reality, a 256 bit key can not be brute forced because of physics - especially the second law of thermodynamics. One of the results of this law is that information needs energy to be represented. In an ideal computer, the representation of one bit requires kT energy, where k is the Boltzman constant and T is the temperature. Let's assume we can operate at the average temperature of 3.2 Kelvin, the average temperature of the universe. The required energy to represent a bit in this case would be around 4.416*10-23 Joule.

The annual amount of energy that our sun emits is about 1.21*10^34 Joule. Dividing this with the per bit-change energy, we could provide power for our ideal computer to perform 2.74*10^56 bit changes. This is just about enough to have a 187-bit counter go through all its states. This does not include the energy needed for the computations to test each key (our counter state in this case) for correctness.

A 256 bit counter would require ~400.000.000.000.000.000.000 stars like our sun just to represent in the counter of our ideal computer.

Or, to say it in the words of Bruce Schneier:
"...brute force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space".

Note: I am not talking about potential attacks against the algorithms here, etc. only pointing out that encryption is definitely not ALWAYS breakable by brute force.

Comment: Re:I see no benefit to me to use, buy bit coins. (Score 1) 134

by PurpleAlien (#47867151) Attached to: Paypal Jumps Into Bitcoin With Both Feet

And the only ones who can mine them are criminals stealing other peoples PC to do the mining. Someone here said its impossible to make a profit mining with one PC as the cost of mining it far greater then the profit.

Bitcoin mining these days is done using ASICS, not PC's...

I see no benefit to me to use, buy bit coins. I use dollars why should I switch unless to do something criminal?

Just because you don't see a benefit, doesn't mean it can't be beneficial to someone else in a different situation from your own. People didn't see much use to oil at first either. Doesn't mean the only other thing one can do with it must be something criminal...

Comment: Re:Assembler only - One Coder - No backdoors. (Score 1) 240

by PurpleAlien (#47586035) Attached to: Getting Back To Coding
If you want to get started with FPGA's, consider the ZedBoard: http://www.zedboard.org/. The Xilinx Zynq offers the best of both worlds; you've got two Cortex A9 ARM codes (with NEON etc.) and FPGA fabric around it where you can implement your own peripherals and communicate with them from the CPU. You can use it as stand alone FPGA or Linux system as well, and gradually start using the 'other' side.

Comment: Re:So just wondering... (Score 3, Informative) 137

by PurpleAlien (#44712483) Attached to: Huge Canyon Discovered Under Greenland Ice
High Coast (Sweden) and Kvarken Archipelago (Finland)

"The geomorphology of the region is largely shaped by the combined processes of glaciation, glacial retreat and the emergence of new land from the sea which continues today at a rate of 0.9 m per century."

Source: http://whc.unesco.org/en/list/898

Comment: Re:Love it (Score 1) 46

by PurpleAlien (#44410907) Attached to: RHex Robot Shows Off Parkour Moves
One of the main reasons the Japanese have been doing so much work on human looking robots is a social problem: they have a graying population (for a long time already), and the goal was to have robots that could replace people taking care of the elderly, disabled, etc. In that use case, it helps to have a robot that looks human instead of a possibly creepy looking machine. Problems such as the 'uncanny valley' issue were intended to be solved as well.

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