Why write cycle time of EEPROM is high?

That is because a write action in an EEPROM involves charging/discharging of a capacitor (a floating gate), which takes a relatively long time time compared to toggling a flipflop in a RAM cell.

Meindert

Writing to a typical nonvolatile memory cell is a completely different process from flipping a bit in an SRAM. See Fowler-Nordheim tunneling and channel hot electron injection. Ferroelectric NVRAM technology (and others such as the new MRAM technology) can give fast write/erase times but they are not in as wide usage at present.

Best regards, Spehro Pefhany

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Why does walking a mile take 15 minutes, when a car can easily do it in 30 seconds?

--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

No that easily. 1 mile in 30 sec is 120 mph, average.

Peter

Damn. That's a pretty fast car.

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Grant Edwards                   grante             Yow!  .. I think I'd
                                  at               better go back to my DESK
                               visi.com            and toy with a few common
                                                   MISAPPREHENSIONS...

What's the speed limit on autobahns, these days?

Not by German standards ;->

Hmm, let's see: 120 mph, that's 193 km/h. Granted, my own car can't do that. But you'll have to believe me when I tell you that driving

100 mph on the Autobahn, which it can do, I still get overtaken by *much* faster cars, about once every 5 minutes.

--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

But thats not comparable to walking a mile, where you start from stopped and finish stopped. The car has to *average* 120 mph, which means peaking at 240 mph to minimize acceleration - you only need 0 to 240 mph in 15 seconds and some damn good brakes!

Peter

That's like saying that having a billion dollars isn't "pretty rich" because there are people who have more than a billion dollars.

I didn't say there weren't cars that couldn't do 120mph easily.

I said that a car that can do that is pretty fast (e.g. in a small minority -- the average car can even come close to doing it). If you don't think a car that can do 120mph easily is pretty fast, then how fast _does_ a car have to go to be considered pretty fast?

I've drivin 100mph on the Autobahn, but the car I was driving (an Audi A4, IIRC) couldn't even do 100 "easily", and it certainly couldn't do 120. The vast majority of other cars I saw on the Autobahn couldn't do 120 at all, let alone easily.

I still think that (even in Germany) a car can do 120mph "easily" is pretty fast.

Motorcycles, OTOH...

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Grant Edwards                   grante             Yow!  ... or were you
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                                                   Tuesday?

Suffice it to say that nobody said anything about starting, much less about stopping at rest. I mean, come on, since when are 100 meter sprinters required to reach the finish line standing still?

Actually, the challenge on the engine would be harder --- brakes routinely achieve higher absolute accelerations than engines. That's apparently even a requirement for getting a vehicle approved for use on public roads, because it means you can always achieve the safe state even if something goes horribly wrong in engine control, just by stomping on the brakes _real_ hard.

--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Not quite. There's a difference between "pretty rich" and "Damn. Pretty rich". OTOH, who knows, there might even be a reason I put a ;-> after that statement...

I'll be selfish: faster than the average car that overtakes me on the Autobahn. I.e. in the upper 50% of all cars going faster than about

155 km/h. I have to guess how fast that actually is, but I'd say it's more than 200 km/h. We have to keep in mind that most of those guys aren't driving at the top speed of their vehicles, either. Their car _can_ go even faster, but their drivers can't. That's because there are too many unbearably slow cars (from their point of view) like mine in the left lane for the real fast ones to come near their top speeds most of the time. They keep having to brake down to 150 km/h or less to avoid crashing into slower vehicles. Not even to mention trucks overtaking trucks, i.e. "unmoving obstacles" in the left lane.

... usually have more sense than to try and go 200 km/h or faster --- wind drag turns into a solid kick in the guts at those speeds.

No, the typical object actually doing over 200 km/h on the Autobahn is a sedan or limousine. Mind you: nothing "sporty" involved. We're talking about working people who value their time high enough not to want to waste it on the road, and have the money to do something about that.

To give you some perspective: my Golf (a.k.a. "Rabbit" overseas) Mk III is 14 years old, and it's really a rather low-end car: this model was available with engines up to three times as powerful as the one I have! But even this low-end car goes 100 mph without breaking too much of a sweat, on level ground and without any wind to help it along.

--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

One would hope so, but a much higher percentage of motorcycles than cars can make it to 120mph.

I wouldn't recommend it without a fairing, but on a faired motorcycle, it's certainly not bad.

True.

Here in the US, they were Rabbits for a while, they were Golfs, now they're back to being Rabbits again. VW really ought to pick a name and stick with it.

There must have been something wrong with the Audi I had on the Autobahn. It took a long time to make it up to 100mph.

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Grant Edwards                   grante             Yow!  I love ROCK 'N
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                               visi.com            all WORDS to "WIPE-OUT"
                                                   in1965!!

David R Brooks schrieb:

Hello,

it depends on location, condition of the autobahn, traffic... You may see 80 km/h, 100 and 120 km/h speed limit, but there are still unlimited parts.

Bye