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Comment: Re:About half (Score 1) 221

by Shirley Marquez (#49505051) Attached to: Norway Will Switch Off FM Radio In 2017

That could be true but the statistics don't support the assertion. Let's have a look:

56% of radio listeners use digital radio every day. That doesn't necessarily mean that the other 44% are using analog radio; it can also mean that some radio listeners do not listen daily.

55% of households have at least one DAB radio. That may not mean the other 45% are listening to analog radios; some of them may not listen to radio at all or only listen to streamed internet radio.

In other words, we need more detailed information before we can determine how much impact this decision will actually have.

Comment: Re:It's a sad day, mate (Score 1) 166

by Shirley Marquez (#49494293) Attached to: 2K, Australia's Last AAA Studio, Closes Its Doors
The tax breaks for the Hobbit filming (and earlier for Lord of the Rings) might have actually worked out for the NZ government because of the huge boon to tourism. But that's a really rare example of an area benefiting from the film industry. Usually they give out lots of tax money with little to show for it; at most you get a minor spike to visits that doesn't cover the expense.

Comment: Re:Did this really need demonstration? (Score 1) 113

by Shirley Marquez (#49465809) Attached to: Turning the Arduino Uno Into an Apple ][

Another factor is that the AVR chips are mostly still 5 volt parts. That means that they have to be made with a very out-of-date process and are much larger than current designs. (The processors used in AVR Arduinos can be run all the way down to 2V at reduced performance, but the fact that they allow 5V operation dictates the process used.) All the microcontroller ARM chips that I am familiar with are 3.3 volt chips (that's the maximum, most can also be run at lower voltages, typically down to 1.8V); higher end ARMs used in phones and the like run at even lower voltages, often less than one volt.

But... being 5 volt chips, they are easier to use in maker designs. Makers tend to still be using older 5 volt CMOS chips for glue rather than low voltage parts. Other things that they want to hook up are likely to run at 5V. 5V means that you can drive every color of LED directly with an output pin rather than needing a level shifter. Low voltage CPUs usually have less current drive capability as well, so even interfacing to other low voltage devices may require the use of buffers. 5V parts have better noise immunity and are less static sensitive.

The Arduino Due, the first ARM-based Arduino, has failed to catch on. One reason is that it is a 3.3V board with inputs that are not 5V tolerant, which means that a large percentage of existing shields and other modules that are designed to be used with Arduino won't work with it. No real fix for that other than releasing new 3.3V shields.

Comment: Re:Did this really need demonstration? (Score 1) 113

by Shirley Marquez (#49431771) Attached to: Turning the Arduino Uno Into an Apple ][

No, ARM isn't more expensive. Try, for example, the ST Microelectronics STM32F030R8T6. That's a Cortex-M0 ARM, 48MHz, 64K flash, 8K RAM, 55 I/O pins. $2.22 in quantity one. Reference: http://www.digikey.com/product... That's just one part I happen to be familiar with; there may be even cheaper ARM alternatives out there.

Quantity one price of an ATMega328? $3.25. That's the surface mount version; the DIP is $3.38. Reference: http://www.digikey.com/product...

It's true that if you stay with Atmel, ARM will be more expensive. The ATSAMD21G18 that is used in the upcoming Arduino Zero Pro is $6.17 in quantity one. Reference: http://www.digikey.com/product... To be fair, that is a newer design using the somewhat more powerful Cortex-M0+ core.

Comment: Re:Did this really need demonstration? (Score 1) 113

by Shirley Marquez (#49431571) Attached to: Turning the Arduino Uno Into an Apple ][

VisiCalc was actually developed on a MicroMind? I didn't know that!

The ECD MicroMind was a tragic example of the perfect being the enemy of the good. It was an ambitious design for the time, notably including memory mapping hardware so the system could have more than 64K RAM, and a powerful graphics board that had both bitmap graphics capability and a programmable character generator. It used stackable boards rather than the usual card slots. But they spent so much time perfecting the design and adding more bells and whistles that they never got the system to the point of being able to be mass produced at a reasonable price.

I knew the guys at the time and hung around at the fringes of the project, though I was never really involved. I think they did use the bitmap chess font I designed for it in the chess program.

Comment: Re:Did this really need demonstration? (Score 1) 113

by Shirley Marquez (#49431343) Attached to: Turning the Arduino Uno Into an Apple ][

The 6500 was MOS Technology's first chip, and sold for $20 in quantity one. It was designed to be pin-compatible with the 6800, though the instruction set was different so it was not a drop-in replacement. The requirement for the quadrature clock was shared with that chip, so it really wasn't any harder to use. MOS Technology withdrew the 6500 from the market under legal pressure from Motorola; MOS Technology probably would have won the legal battle but did not have the resources to fight it.

Meanwhile they had been working on their second product, the 6502. The new chip incorporated the quadrature clock generator in the CPU, so there was no longer a need to generate it externally. (Generating quadrature clocks is not all that difficult - the circuit involves two flip-flops - the main wrinkle is that they have to be non-overlapping, requiring some attention to circuit layout and stray capacitance.) The 6502 also rearranged the pins so it was no longer pin-compatible with the 6800, satisfying Motorola's lawyers. The new chip was easier to use so they raised the price a bit to $25 in quantity one.

Many modern microprocessor designs use quadrature clocks, but they are generated on-chip now just like the 6502. Any microcontroller that takes a clock input that is four times the actual clock speed of the processor uses a quadrature clock. In current designs it's harder to tell because they also often incorporate on-chip PLL clock multipliers, so the actual clock rate of the chip is many times the speed of the external clock. x86 processors are one extreme example; they use a 100 MHz external clock and may multiply it by 40x or more.

Comment: Re:Did this really need demonstration? (Score 1) 113

by Shirley Marquez (#49431167) Attached to: Turning the Arduino Uno Into an Apple ][

Mostly the 6502 was cheap because they made a marketing decision to make it cheap. The convention wisdom of the time was to charge through the nose for small quantities of chips and soak developers. In theory this helped companies keep down the large volume prices of their chips and make them more attractive to companies that were going to buy millions of them. MOS Technology, a startup chip maker, decided to try something radical to put itself on the map: sell single chips at prices low enough that hobbyists and garage startups could afford them. It paid off; Apple's decision to use the 6502 was largely motivated by the low price of the chip.

After MOS Technology went away, the industry returned to business as normal for many years, again charging high prices for small quantity orders and especially for evaluation boards. But that has changed in recent years. We now have a flood of inexpensive evaluation boards for all sorts of microcontrollers - not just open hardware projects like Arduino, but also boards from manufacturers such as the TI Launchpad series and the mbed. The maker movement has been a big beneficiary of the change. The software situation has also improved: we now have open-source tools based on GCC as an alternative to expensive embedded system compilers and debuggers.

Comment: Re:And redundancies come through faster as well! (Score 1) 330

by Shirley Marquez (#49412791) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

The ugly comes along with the low drag coefficient. Giving up the low drag coefficient would mean less range. Of course it's also true that designing gas powered cars like that would mean better fuel mileage, so we may yet see it.

One of the nice things about an electric car is that stop and go driving doesn't hurt its range much, at least if the weather is sufficiently pleasant that you don't need to run the heater or the air conditioner. Electric cars have regenerative braking so much of the energy is recovered if you brake, and a stopped electric car uses no power at all.

Comment: Did they have any other offers? (Score 1) 249

by Shirley Marquez (#49407207) Attached to: Sony Buys, Shuts Down OnLive
One thing I haven't seen addressed in any of the news reports is whether OnLive was financially viable. If they were having trouble keeping the lights on and they couldn't find a way to make the numbers work, then I really can't blame them for taking what they could get. On the other hand, if they sold just because somebody put a bunch of money on the table to shut them down, I'm inclined to say that they should have refused the deal.

"You must have an IQ of at least half a million." -- Popeye

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