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PressureSensor-another possibility — Parallax Forums

PressureSensor-another possibility

ArchiverArchiver Posts: 46,084
edited 2004-03-08 14:49 in General Discussion
> Interesting comment. Visual representation of pressure could be
> brightness, but that is often relative to the ambient lighting.
> Flashing could be more accurate, and series of flashes could offer
> more accurate and more useful information.
>
> Dave

I would have to agree that a varying LED output would be hard to
really make any visual reference that would be useful (unless you need
to know an on-off situation). I would like to suggest a possibility.
I've been working on an altimeter project with a variometer, which
measures the rate of altitude change. One project is an audio only
vario that uses sound to signify the rate. The pressure signal is
differentiated and amplified with an op-amp, then the signal is sent
to pin 5 of a 555 timer which controls the pitch. The same idea here
could be used by setting up the timer to focus on pulses instead of
pitch so that you get a blinking light rather than different light
intensities. This should work well for you, but then I don't know
exactly what it's for. I noticed by your part number that you're also
using a differential sensor rather than an absolute, so my guess is
you're reading the difference between two areas. I could be wrong,
but it's a guess. Anyway, let me know if the timer idea would help.

David

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-03-08 06:25
    hello all,

    and thanks for the help. The variable intensity LED is a must for my project, I
    need it for a particular aesthetic/visual affect.

    David Kissick <geckoinc99@y...> wrote:
    > Interesting comment. Visual representation of pressure could be
    > brightness, but that is often relative to the ambient lighting.
    > Flashing could be more accurate, and series of flashes could offer
    > more accurate and more useful information.
    >
    > Dave

    I would have to agree that a varying LED output would be hard to
    really make any visual reference that would be useful (unless you need
    to know an on-off situation). I would like to suggest a possibility.
    I've been working on an altimeter project with a variometer, which
    measures the rate of altitude change. One project is an audio only
    vario that uses sound to signify the rate. The pressure signal is
    differentiated and amplified with an op-amp, then the signal is sent
    to pin 5 of a 555 timer which controls the pitch. The same idea here
    could be used by setting up the timer to focus on pulses instead of
    pitch so that you get a blinking light rather than different light
    intensities. This should work well for you, but then I don't know
    exactly what it's for. I noticed by your part number that you're also
    using a differential sensor rather than an absolute, so my guess is
    you're reading the difference between two areas. I could be wrong,
    but it's a guess. Anyway, let me know if the timer idea would help.

    David



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  • ArchiverArchiver Posts: 46,084
    edited 2004-03-08 14:49
    How about flashing the led 0 to 10 times
    0 flashes 0 pressure
    10 flashes 10 or 100 psi



    Larry Gaminde
    Original Message
    From: "gooey" <cantyant@y...>
    To: <basicstamps@yahoogroups.com>
    Sent: Sunday, March 07, 2004 10:25 PM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: PressureSensor-another possibility


    hello all,

    and thanks for the help. The variable intensity LED is a must for my
    project, I need it for a particular aesthetic/visual affect.

    David Kissick <geckoinc99@y...> wrote:
    > Interesting comment. Visual representation of pressure could be
    > brightness, but that is often relative to the ambient lighting.
    > Flashing could be more accurate, and series of flashes could offer
    > more accurate and more useful information.
    >
    > Dave

    I would have to agree that a varying LED output would be hard to
    really make any visual reference that would be useful (unless you need
    to know an on-off situation). I would like to suggest a possibility.
    I've been working on an altimeter project with a variometer, which
    measures the rate of altitude change. One project is an audio only
    vario that uses sound to signify the rate. The pressure signal is
    differentiated and amplified with an op-amp, then the signal is sent
    to pin 5 of a 555 timer which controls the pitch. The same idea here
    could be used by setting up the timer to focus on pulses instead of
    pitch so that you get a blinking light rather than different light
    intensities. This should work well for you, but then I don't know
    exactly what it's for. I noticed by your part number that you're also
    using a differential sensor rather than an absolute, so my guess is
    you're reading the difference between two areas. I could be wrong,
    but it's a guess. Anyway, let me know if the timer idea would help.

    David



    To UNSUBSCRIBE, just send mail to:
    basicstamps-unsubscribe@yahoogroups.com
    from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.

    Yahoo! Groups Links








    Do you Yahoo!?
    Yahoo! Search - Find what you’re looking for faster.

    [noparse][[/noparse]Non-text portions of this message have been removed]



    To UNSUBSCRIBE, just send mail to:
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