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If you want to have 1 as an output if either of two inputs are 1, why don you need an IC gate when you can just connect two wires and have one output from them?
Power.
With CMOS technology, which is pretty much everything these days, a gate drives a one by connecting the output to the +ve power rail. It drives a zero by connecting the output to ground. If you have two gates driving a single wire, one is driving high, and the other is driving low, you create a path that is connecting the power rail to ground. This will give continuous current flow and cause lots of power to be dissipated.
It also doesn't give the result you want, because the voltage on the shared output will tend to float around the centre value(*). Neither zero or one. The circuit ends up being a potential divider.
(*) assuming the size of the transistors pulling up/down is about equal.
Check out wired-OR.
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i wonder how the real time data from microcontroller (TMS320F28835) can be displayed on 7-segment. I can view the data(float or int data type) on expression window in code composer studio but i want to display that data on 7 segment(SND3360). Need help for this problem. Any refernece code or manual for this problem will be helpful.
Looking for reference code or technical manual.
The SND3360 is a very basic 6 digit display with no controller/multiplexer. For each digit you must have all the common cathode digit pins normally high, then set the segment pins for one digit and pull its cathode low to illuminate the selected LEDs. You would after a short delay reset the cathode high, then repeat for the next digit. By cycling through each digit rapidly and regularly persistence of vision will give the impression that all 6 digits are displayed.
You need to do this in software in such a way that the digit refresh rate is not affected but other code running. One way of doing that is to update the display in a timer interrupt handler or a high priority RTOS thread.
A hardware solution (and therefore off-topic) is to use a BCD to 7-Segment display decoder (e.g. CD5411to drive the segment pins, in that case your MCU needs just 4 pins instead of 8 to define the digit, and then 6 lines to select the digit - you could further use a multiplexer (e.g. 74137) to select one of 6 digit pins using just three GPIO, so with the BCD decoder and output multiplexer, you can connect the display using just 7 GPIO rather than 14 driving it directly from MCU GPIO. It also simplifies the software.
Even simpler is to use a controller chip specifically designed to drive exactly this type of display. For example the STLED316S. That can be driven from a three-wire serial interface. The controller handles all the multiplexing and refresh for you.
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I'm new to blender. I want to restore sharp edge and create vertex that is geometrically intersection of selected triangles. Is there fast way to do this?
selected triangles are orange
This isn't very easy to do without changing the volume of the mesh, but here's the best method I've found:
Select the whole mesh (Or just the bevelled faces you want to sharpen):
Select the "Shrink/fatten" tool from the toolbar:
Shrink the faces, until the vertices at the corners are overlapping.
IMPORTANT: if you want to preserve the volume of the object, make sure to make a note of the exact value that you shrank the mesh by (visible in the bottom left of the screen):
Press the M key and select Merge by distance (or go to Mesh > Merge > By distance), and increase the Merge distance parameter until all of the vertices double vertices have been merged:
Finally, use the shrink/fatten tool again to resize the mesh to its original volume. (If you want to be exact, use the negative version of the amount you shrunk it by to begin with):
Bonus tip, if you want to get rid of the annoying triangles on the faces, you can use the Tris to quads operator to remove them.
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Is GPS data signed and timestamped by the satellite?
No, GPS is not signed. I think there may be in future some signed signals. Maybe it is used on military part of GPS.
GPS spoofing is a well know problem, and problems are usually "solved" in hardware. If signal strength on some satellites changes quickly: do no trust it. Multiple antenna (on extreme of lorry/ship) and comparing strength of signal helps. Some directional antenna helps to know that signal expected from a satellite come from where it is expected. And often some gyroscope, compass, or and tracking, to check plausibility of data.
Note: fishing boat uses it to decoy own position (in protected area/economic exclusive zones). They causes a lot of troubles to other ships and boats (and sometime to ground equipment).
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Inspired by a recent Kickstarter campaign: http://www.kickstarter.com/projects/dominikmazur/camfind-a-mobile-visual-search-app?ref=category
The app uses the mobile camera to take a picture and identify virtually any object. Snapping a photo of a movie poster will recognize the movie and pull up results on the web for you about it, taking a picture of a product will show you websites that product is available for sale on.
My question is, is this realistic? I find it very intriguing, but it object detection really that simple? I'm interested in some feedback regarding resources to help someone get started in learning about this topic.
Computer vision and Pattern Recognition is not easy at all. It's an entire field related to Artificial Intelligence. It is, however, relatively straightforward to understand at a high level though. There is NO WAY they are doing this all on the client. The phones just aren't fast enough, and do not have even close to enough storage space.
What they are most likely doing is sending the image to their servers, then use some kind of nearest neighbour approximation on the image, and run the result through a decision tree look-up in a massive database on images which all have some hash. This will give a close match to an image they have (assuming they have A LOT of images in there database), even if only part of the image matches. Then, using the hash, they look up some other information about that image to send to the device.
Hope that Helps!
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My teenage step-daughter is autistic, and tends to want to run away from school, leisure-club and sometimes even from home. This is very bad for her safety, and a great concern for us.
I am looking for a way to track her, so we can find her again when she runs away.
Here is my ideal (possibly unrealistic) scenario:
Tiny GPS device with GSM/GPRS
Can be woken up via sms when needed (so battery will last longer)
When activated, spins up GPS + Data connection and starts hitting a predefined URL with device ID and long+lat every 15 seconds
Battery life 7 days on standby (ie. when never activated)
Can be disabled put back to sleep via sms
I have googled and researched this for a while, but have yet to find a device that fits these requirements.
The solution could also be a mobile phone of some sort, that I can lock down.
You could do most of that with any Android handset using prey
http://preyproject.com/blog/2010/01/prey-arrives-on-mobiles-android-version-available