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Nick Guest
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varible knob for input |
Posted: Sun Mar 06, 2005 6:24 pm |
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i need to get input from a knob, this knob needs to keep its position even when turned off and back on.
maybe a pot attached to a analog line?
Nick |
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dyeatman
Joined: 06 Sep 2003 Posts: 1934 Location: Norman, OK
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Posted: Sun Mar 06, 2005 6:39 pm |
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Sounds like the teacher assigned this project again this year....
This has been covered in this forum before. Search on the word "pot" |
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Guest
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Posted: Sun Mar 06, 2005 6:53 pm |
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i did to a search and i found my old post from a few months ago, but didnt seem like i got a straight answer.
btw i'm not in school.
Nick |
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dyeatman
Joined: 06 Sep 2003 Posts: 1934 Location: Norman, OK
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Posted: Sun Mar 06, 2005 7:07 pm |
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OK then, when you post something like this you need to give sufficient info to work with. Can you give some more information about the following:
1. what version of compiler are you using?
2. What PIC are you using?
3. can you describe the application and how the pot is intended to work? |
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Mark
Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA
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Posted: Sun Mar 06, 2005 8:07 pm |
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How about asking a question? You made a couple of statements and a viable solution. What else are you looking for? Alternatives? What you have posted is probably the easiest. I don't think you want to go the route with an encoder. |
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Nick Guest
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Posted: Sun Mar 06, 2005 9:23 pm |
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sounds good, I just wanted to know if it was a viable solution.
Nick |
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SherpaDoug
Joined: 07 Sep 2003 Posts: 1640 Location: Cape Cod Mass USA
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Posted: Mon Mar 07, 2005 7:58 am |
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There are "absolute" position encoders that give you a 3 or 4 bit indication of their current position. For very large $$$ you might be able to buy an 8 bit absolute encoder, but I have never seen one.
For almost all applications the pot and A/D is the way to go. _________________ The search for better is endless. Instead simply find very good and get the job done. |
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sseidman
Joined: 14 Mar 2005 Posts: 159
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Posted: Mon Mar 14, 2005 5:05 pm |
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SherpaDoug wrote: | ...
For almost all applications the pot and A/D is the way to go. |
I'm moving away from this approach. An encoder is much more flexible, and you can use one encoder to control multiple parameters. Values can be save in ROM, and restored on boot. Noise is less of an issue, and you pretty much define the resolution of the encoder. You can use it for course and rough adjustments.
My digital oscilloscope is what sold this approach for me. It has a context-sensitive knob that I wouldn't change for anything.
Scott |
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