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Comment Re:Allow me to predict the comments (Score 1) 230

At this size and price, Pi is going to take a serious bite out of the Arduino community.

It will take some, but the AVR (not necessarily Arduino) still has a few distinct advantages for some applications. TheRPi is a 3.3V device and the GPIO pins are NOT 5V tolerant. There's a lot of nice TTL hardware out there that it won't play nice with. Meanwhile, you can get a very small pro-mini clone from China for $2 each. The other area the RPi won't touch is extreme low power. If you remove the regulator and power LED (or on the pro-mini, cut the solder link to them), you can drop to 10s of micro-amps in various sleep modes and wake on pin-change interrupts or the watchdog timer. That makes a big difference if you want to run it on a LiIon battery. If you underclock the AVR (using the clock divider register) it can easily operate reliably down to the low cutoff voltage of the battery.

That's not meant to take anything from the Pi zero. It opens a lot of possibilities where you need more CPU power than the AVR can offer.

Comment Re:Lithium Ion? (Score 1) 44

They chose one of the more expensive commercially available battery technologies for their flow battery?

No. It is not more expensive, it is cheaper. Most existing flow batteries are vanadium redox. Vanadium is about $40/kg. Lithium costs about double that, but it has much higher energy density, so it is cheaper per unit of energy stored.

Yep, and that is because what you are interested in for a flow battery is the number of $/mole, not the $/kg.
This is roughly proportional (by Avogadro's number) to $/electron
Vanadium atomic mass ~ 51. A kg would be about 20 moles, so at $40/kg the price is $2/mole
Lithium atomic mass ~ 7. A kg would be about 143 moles, so at $80/kg Lithium is $0.56/mole

Comment Re:Not replaced: serial and parallel ports. (Score 1) 241

That's because most (but not all) USB serial devices use +5/0v rather than +/-12V. Most but unfortunately not all of them are tolerant of +-12V. By the same token, some 12V serial devices will communicate with a TTL serial port and some won't.

Going by spec, it's the TTL level port's fault if they don't communicate, but it's so common these days we might as well consider TTL the standard and 12V operation is a bonus.

The TTL level ports started showing up well before USB was a thing.

Just to make it worse, there are now 3.3V "serial" ports in the wild and some of them do not tolerate TTL levels! That's not good, but at least they are implemented only as header pins on the board and not a 9 pin D.

Comment Re:Not replaced: serial and parallel ports. (Score 1) 241

It may be excessive in some sense, but USB serial has absolutely replaced serial ports on desktop and laptop machines. I can get all the serial ports I want by plugging in inexpensive USB serial devices. The microcontroller in the device may be excessive, but no more so than the glue logic for a PCI device would be just to transmit at 115,200 bpx MAX.

I agree completely on the parallel port. The only remaining use I have for a parallel port is as poor man's GPIO lines. Unfortunately, for reasons that elude me, the standard for USB parallel ports doesn't accommodate that at all.

Comment Neither - for what *I* need (Score 1) 112

I've just been investigating this very question. I'm develop a tertiary course in "software engineering process". Small teams will need to work together to build *something*. For a variety of reasons, we think that building an embedded system would be a good thing for them to have exposure to, so I'm trying to find a suitable platform to develop on. The current Raspberry Pi and Beaglebone Black both have their strengths and weaknesses, but both would do for the job. But they both cost at least 50 AUD, which is affordable but not equivalent to zero for planning purposes. By contrast, both the C.H.I.P. and the Pi zero are so cheap that the cost can be ignored. However, both platforms require you to break out the soldering iron if you want to attach things to the GPIO ports. By the time you have something you can hook things up to without soldering, you're back up to the cost of a standard Pi anyway.

Comment Re:WD Black the 3rd most broken item (Score 1) 98

That used to be expected in the U.S. as well. Take it back to the store, show that it doesn't work and a receipt to show when you bought it. Leave with a new one.

Really, it makes sense. The store is the one that has a business relationship with the manufacturer. You bought the item from the store.

If the brick and mortar stores in the U.S. hadn't stopped doing that, they might stand a chance against online retailers.

Comment Re:Important to note (Score 1) 421

It's almost as if the antis just wanted to force others to bow to their will and now they're ticked off that there is a solution that invalidates their best "objective" arguments. Thus they must stomp it out so they can go back to demanding that others bow to their will.

If they were actually objectively concerned about people's health or even the costs to society, they'd be dancing in the streets and arranging to get ecig starter kits to all smokers.

Comment What scares me here (Score 4, Insightful) 36

is that reading and exploiting data that's a mere 25 years old requires almost archeological-like recovery and reconstruction techniques. Compare that to a thousand year old book that's usually pretty much readily readable today.

I think modern society is on a scary path towards massive amnesia in the not-so-long term...

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