you'll end up having to create an account and "directly kick a few dollars" for a month's subscription to read the full text of even one article whose abstract you found through a search engine
One time I got a bunch of boards made in China that specified a Molex part. They substituted it with a Chinese replica that fitted quite poorly to the original Molex mating part. I guess they were 90% indistinguishable.
except when their duty cycle or rise time is not compatible with the SOC
Very hypothetical problems.
except when the oscillator costs more than the SOC (look up parts costs! you will be shocked at what oscillators cost)
I know they cost more, but for low volume, that's usually not a big deal. If you use a DIP type, you can even put a socket on the board, and borrow oscillators from another project.
this is not due to an "accurate" rc oscillator, this is because the USB host generates a pulse of precise duration and the USB device can calibrate its oscillator to the pulse duration.
For the purpose we're talking about, the RC oscillator is accurate. Whether they achieve this by design, or by continuous calibration isn't really relevant for most people.
I have no idea what the top German/Chinese/Russian/Israeli engineering schools are either, still there are many more Arabs driving German cars, than the other way around.
Or you could use a canned crystal oscillator instead. These are quite fool proof.
Or pick a controller that doesn't need a crystal. Modern controllers have factory calibrated internal oscillators good enough to run a UART port. I even saw one that could run USB without a crystal.
First, don't roll your own PCB with a microcontroller on it unless you know what you're doing. This is an involved process and not for newbies
It's pretty easy, actually, if you follow a few simple guidelines. Put a bypass cap on the power leads, and put the crystal close to the CPU (if you need a crystal). Check the datasheet for other helpful advice. Often there will be a minimum schematic shown. Look at schematics of existing boards to see what they do.
It's not a bad idea to put holes or pads for despiking capacitors all over the board, at least one per chip in your design.
I always do one capacitor per power supply lead. And they always get populated. Unless you make high volume (thousands), there's no sense in optimizing.
If you read that link a bit closer, you see it was not a prediction. This is what they really said:
"Given the estimated trend and the volume estimate for October–November of 2007 at less than 9,000 km3, one can project that at this rate it would take only 9 more years or until 2016 ± 3 years to reach a nearly ice-free Arctic Ocean in summer. Regardless of high uncertainty associated with such an estimate, it does provide a lower bound of the time range for projections of seasonal sea ice cover"
Which says: "If current climatological conditions are sustained, the ice fields atop Kilimanjaro and on its flanks will likely disappear within several decades,". That study was done in 2002, and at that time, about 80% of the ice pack was already gone, and the remainder was still shrinking. There's still a few years left until the prediction, and even if it misses it by a few years, that's not what's important here.
That seams like a reasonable statement... I don't know if it is true or not, I don't know if the increase in CO2 is really our doing, or if there is another cause...
The total amount of CO2 in the atmosphere can be calculated, and we also have data on fossil fuels we're burning. If you do the math, it shows that the CO2 produced by fossil fuel burning is about twice the increase in the atmosphere. The other half is taken up by plants and the ocean. So, yes, it is our doing.
Also, if the cause were something like increased volcanic activity, you'd see sudden spikes in the graph at times of large eruptions, instead of a gradual increase (the yearly wave is due to seasonal influence on vegetation, which is mostly in the northern hemisphere).
In addition, we see that O2 levels are decreasing in a way that's consistent with burning carbon, and the carbon isotope ratio tells us its old carbon.
I don't have a problem with any of that... The issue is that the extremist AGW people want to triple all of it and do it tomorrow at any cost...
Looking at the graph of the CO2, http://www.esrl.noaa.gov/gmd/c... I don't see any signs of slowing down thanks to the changes we've already implemented. Clearly, it's not enough.
Slashdot Mirror
So again, if we were to get rid of ads, what would we replace them with?
Frankly, I don't give a shit. I'll continue to block the ads on my browser, and the content hosting company can figure out how to get their money.
you'll end up having to create an account and "directly kick a few dollars" for a month's subscription to read the full text of even one article whose abstract you found through a search engine
I'll just read the Slashdot summary.
Maybe to allow for higher input voltage.
And as a side benefit, they'll learn how to launch ICBMs at the same time.
One time I got a bunch of boards made in China that specified a Molex part. They substituted it with a Chinese replica that fitted quite poorly to the original Molex mating part. I guess they were 90% indistinguishable.
except when their duty cycle or rise time is not compatible with the SOC
Very hypothetical problems.
except when the oscillator costs more than the SOC (look up parts costs! you will be shocked at what oscillators cost)
I know they cost more, but for low volume, that's usually not a big deal. If you use a DIP type, you can even put a socket on the board, and borrow oscillators from another project.
this is not due to an "accurate" rc oscillator, this is because the USB host generates a pulse of precise duration and the USB device can calibrate its oscillator to the pulse duration.
For the purpose we're talking about, the RC oscillator is accurate. Whether they achieve this by design, or by continuous calibration isn't really relevant for most people.
I have no idea what the top German/Chinese/Russian/Israeli engineering schools are either, still there are many more Arabs driving German cars, than the other way around.
Or you could use a canned crystal oscillator instead. These are quite fool proof.
Or pick a controller that doesn't need a crystal. Modern controllers have factory calibrated internal oscillators good enough to run a UART port. I even saw one that could run USB without a crystal.
First, don't roll your own PCB with a microcontroller on it unless you know what you're doing. This is an involved process and not for newbies
It's pretty easy, actually, if you follow a few simple guidelines. Put a bypass cap on the power leads, and put the crystal close to the CPU (if you need a crystal). Check the datasheet for other helpful advice. Often there will be a minimum schematic shown. Look at schematics of existing boards to see what they do.
It's not a bad idea to put holes or pads for despiking capacitors all over the board, at least one per chip in your design.
I always do one capacitor per power supply lead. And they always get populated. Unless you make high volume (thousands), there's no sense in optimizing.
Posting a link to one story does not shove another out of the way.
Yes, it does. Quite literally, in fact. There's only so much room on the front page.
building a Long Term Space Habitat stationed at a lagrange point
Or on earth, which is just as useful, but a lot cheaper.
If you click on the first "Mars" link in the article, it takes you to the Mars food company.
Do you write about the "Caucasian Moon missions"
Maybe, if they were launched from the United Caucasian States of America.
If you target an audience that's too big, the actual audience becomes smaller.
What always happens is that these people all seem to be capable of finding other work
So far.
When there are no more unskilled jobs left, the people who can't get skills will not get a replacement job.
Tractor trailers are not only difficult to maneuver, but often require very difficult maneuvers to park where they can be unloaded or unhitched.
Sounds like a perfect job for a computer to solve.
The next stage is for users to download the ads, but don't show them on the screen.
In Soviet Russia, insurance company pays you!
If you read that link a bit closer, you see it was not a prediction. This is what they really said:
"Given the estimated trend and the volume estimate for October–November of 2007 at less than 9,000 km3, one can project that at this rate it would take only 9 more years or until 2016 ± 3 years to reach a nearly ice-free Arctic Ocean in summer. Regardless of high uncertainty associated with such an estimate, it does provide a lower bound of the time range for projections of seasonal sea ice cover"
"If current climatological conditions are sustained"
Obviously, if you change the current conditions, because some people are alarming you of the consequences, you can change the outcome.
the snows of Kilimanjaro were supposed to all have melted by now
Are you referring to this:
http://www.independent.co.uk/e... ?
Which says: "If current climatological conditions are sustained, the ice fields atop Kilimanjaro and on its flanks will likely disappear within several decades,". That study was done in 2002, and at that time, about 80% of the ice pack was already gone, and the remainder was still shrinking. There's still a few years left until the prediction, and even if it misses it by a few years, that's not what's important here.
That seams like a reasonable statement... I don't know if it is true or not, I don't know if the increase in CO2 is really our doing, or if there is another cause...
The total amount of CO2 in the atmosphere can be calculated, and we also have data on fossil fuels we're burning. If you do the math, it shows that the CO2 produced by fossil fuel burning is about twice the increase in the atmosphere. The other half is taken up by plants and the ocean. So, yes, it is our doing.
Also, if the cause were something like increased volcanic activity, you'd see sudden spikes in the graph at times of large eruptions, instead of a gradual increase (the yearly wave is due to seasonal influence on vegetation, which is mostly in the northern hemisphere).
In addition, we see that O2 levels are decreasing in a way that's consistent with burning carbon, and the carbon isotope ratio tells us its old carbon.
There are no volcanoes under the Larsen B ice shelf.
I don't have a problem with any of that... The issue is that the extremist AGW people want to triple all of it and do it tomorrow at any cost...
Looking at the graph of the CO2, http://www.esrl.noaa.gov/gmd/c... I don't see any signs of slowing down thanks to the changes we've already implemented. Clearly, it's not enough.