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Pushbutton of 300 ft. away — Parallax Forums

Pushbutton of 300 ft. away

ArchiverArchiver Posts: 46,084
edited 2002-02-21 08:47 in General Discussion
I need to tight up a push button for Stamp II. That is not complicated since
we just need to use a 5V to any pin via a 100K resistor, in between using an
on / off switch to ground. The Stamp detect a LOW on pressing button. Stamp
is nice with Button command for debounce key press.

However, what about if I need to use the button from 300 feet away from the
Stamp? Do I do the same as above? Should I use another stamp with RS485 to
connect the two stamps? Is there any simpler way to do it?

Thanks for any advice.

John Leung

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2002-02-20 02:39
    Go wireless! http://www.al-williams.com/awce/som.htm

    Good luck!

    Al Williams
    AWC
    * Easy RS-232 Prototyping
    http://www.al-williams.com/awce/rs1.htm



    >
    Original Message
    > From: John Leung [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Rj4EsArxjSjZSeTJ29Btz7u9evkpZUwlnmfvoiut51Zg2l6BHbbLKQdQYj4oV-bXzqwUcQUP_vqQqxkpBPulo3o]jleung00@n...[/url
    > Sent: Tuesday, February 19, 2002 8:36 PM
    > To: basicstamps@yahoogroups.com
    > Subject: Re: [noparse][[/noparse]basicstamps] Pushbutton of 300 ft. away
    >
    >
    > I need to tight up a push button for Stamp II. That is not
    > complicated since we just need to use a 5V to any pin via a
    > 100K resistor, in between using an on / off switch to ground.
    > The Stamp detect a LOW on pressing button. Stamp is nice with
    > Button command for debounce key press.
    >
    > However, what about if I need to use the button from 300 feet
    > away from the Stamp? Do I do the same as above? Should I use
    > another stamp with RS485 to connect the two stamps? Is there
    > any simpler way to do it?
    >
    > Thanks for any advice.
    >
    > John Leung
    >
    >
    >
    > 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.
    >
    >
    > Your use of Yahoo! Groups is subject to
    > http://docs.yahoo.com/info/terms/
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-20 03:48
    Dear Al

    Very sorry that I have not explained my situation very clear. In fact the
    other side is also a standard printing device. I need to send data from the
    Stamp to that printing device from 300 ft. too. Because I need to add a push
    button to the printing device such that when the button is pressed, Stamp
    get signal and sending data to printing device. For sending data from stamp
    to printer, I have found a useful app note about SN75176 (RS485). However,
    how to handle the push button them?

    I don't know if it is possible to simply put 5V and ground and a press
    button to 300ft apart from the stamp. Should I use some sort of voltage
    up/down for transmitting the voltage signal for long distance? Or else there
    is other better way to do the job.

    The following diagram shows my concern:


    5V
    ......300 ft away
    100K---| Stamp pin 0 (say)
    --|-push button
    ..............................
    | stamp
    GND
    GND



    John

    Original Message
    From: Al Williams <alw@a...>
    To: <basicstamps@yahoogroups.com>
    Sent: Wednesday, February 20, 2002 10:39 AM
    Subject: RE: [noparse][[/noparse]basicstamps] Pushbutton of 300 ft. away


    > Go wireless! http://www.al-williams.com/awce/som.htm
    >
    > Good luck!
    >
    > Al Williams
    > AWC
    > * Easy RS-232 Prototyping
    > http://www.al-williams.com/awce/rs1.htm
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-20 04:07
    Why not use a serial printer (Epson LX300+) and use the pause button on the
    printer to do what you need to do. We easily got 500' with the right cable
    and a Max232 on the source of the serial data.

    Original Message

    > Very sorry that I have not explained my situation very clear. In fact the
    > other side is also a standard printing device. I need to send data from
    the
    > Stamp to that printing device from 300 ft. too. Because I need to add a
    push
    > button to the printing device such that when the button is pressed, Stamp
    > get signal and sending data to printing device. For sending data from
    stamp
    > to printer, I have found a useful app note about SN75176 (RS485). However,
    > how to handle the push button them?
    >
    > I don't know if it is possible to simply put 5V and ground and a press
    > button to 300ft apart from the stamp. Should I use some sort of voltage
    > up/down for transmitting the voltage signal for long distance? Or else
    there
    > is other better way to do the job.
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-20 05:11
    At 10:36 AM 2/20/02 +0800, John Leung wrote:

    >However, what about if I need to use the button from 300 feet away from the
    >Stamp? Do I do the same as above? Should I use another stamp with RS485 to
    >connect the two stamps? Is there any simpler way to do it?

    300 Feet is no problem if you are careful.

    I'd use shielded twisted pair cable, with the shield connected to circuit
    Gnd at the stamp end only. Use a 1K pullup resistor on the switch, with a
    10K series between the switch and the stamp. Adding a small bypass
    capacitor (0.1 uF) from the stamp pin to Gnd will reduce noise pickup. Be
    sure to delay a short time when first starting up after applying power: the
    bypass cap will look like a momentary switch closure until it
    charges. This is less than 10 ms - usually no problem at all. But you
    need to be aware of it.

    Vdd
    |
    1K
    long cable |
    but o
    +---- 10K---+--- Stamp Pin
    but o
    + |
    sh o---+ | 0.1 uF cap
    | | |
    gnd gnd gnd

    dwayne


    Dwayne Reid <dwayner@p...>
    Trinity Electronics Systems Ltd Edmonton, AB, CANADA
    (780) 489-3199 voice (780) 487-6397 fax

    Celebrating 18 years of Engineering Innovation (1984 - 2002)
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  • ArchiverArchiver Posts: 46,084
    edited 2002-02-20 14:30
    I'm not sure if I fully understand your question, but it sounds like a
    4-20mA current loop would work here. This is a standard for transmitting
    signals long distances in noisy environments.
    --
    Greg

    John Leung wrote:
    >I need to tight up a push button for Stamp II. That is not complicated since
    >we just need to use a 5V to any pin via a 100K resistor, in between using an
    >on / off switch to ground. The Stamp detect a LOW on pressing button. Stamp
    >is nice with Button command for debounce key press.
    >
    >However, what about if I need to use the button from 300 feet away from the
    >Stamp? Do I do the same as above? Should I use another stamp with RS485 to
    >connect the two stamps? Is there any simpler way to do it?
    >
    >Thanks for any advice.
    >
    >John Leung
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-20 18:20
    Check out some manufacturers web sites for application notes describing the
    4-20mA current loop in detail. It is intended for transmitting an analog
    signal, but I was thinking you could also use it as either an ON/OFF signal
    too (e.g., across 250 ohms 4mA would give 1V for low and 20mA would give 5V
    for high).
    --
    Greg

    John Leung wrote:
    >Dear Gregory
    >
    >First of all, thanks for your advice. Could you elaborate more?
    >
    >Thanks for your help in advance.
    >
    >John
    >
    >
    >
    Original Message
    >From: "Gregory D Wagner" <gregory-wagner@u...>
    >To: <basicstamps@yahoogroups.com>
    >Sent: Wednesday, February 20, 2002 6:30 AM
    >Subject: Re: [noparse][[/noparse]basicstamps] Pushbutton of 300 ft. away
    >
    >
    > > I'm not sure if I fully understand your question, but it sounds like a
    > > 4-20mA current loop would work here. This is a standard for transmitting
    > > signals long distances in noisy environments.
    > > --
    > > Greg
    > >
    > > John Leung wrote:
    > > >I need to tight up a push button for Stamp II. That is not complicated
    >since
    > > >we just need to use a 5V to any pin via a 100K resistor, in between using
    >an
    > > >on / off switch to ground. The Stamp detect a LOW on pressing button.
    >Stamp
    > > >is nice with Button command for debounce key press.
    > > >
    > > >However, what about if I need to use the button from 300 feet away from
    >the
    > > >Stamp? Do I do the same as above? Should I use another stamp with RS485
    >to
    > > >connect the two stamps? Is there any simpler way to do it?
    > > >
    > > >Thanks for any advice.
    > > >
    > > >John Leung
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-21 03:55
    The unit I used to support used a 8051 variety processor communicating at
    300 baud with an Epson LX300 or LX300+ printer using a MAX232 on the
    processor end. We used Belden 8770 (If I remember right) cable, which is a
    3-conductor shielded cable. The BUSY line from the printer signaled the
    processor it was ok to print. The printers are still available through
    various sources for under $200.

    Original Message

    > Since we are looking forward to some sort of thermal ticket printer, and
    > there is hardly any button on it, so I need to modify a little bit. Do you
    > mean MAX232 with the right cable (high quality shield, twist pair cable)
    > will do the job of transmission over 500 ft? I really need to experiment
    > with that.
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-21 07:59
    Dear Rodent

    Since we are looking forward to some sort of thermal ticket printer, and
    there is hardly any button on it, so I need to modify a little bit. Do you
    mean MAX232 with the right cable (high quality shield, twist pair cable)
    will do the job of transmission over 500 ft? I really need to experiment
    with that.

    Do you have any experience with that?

    John

    Original Message
    From: "Rodent" <daweasel@s...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, February 19, 2002 8:07 PM
    Subject: Re: [noparse][[/noparse]basicstamps] Pushbutton of 300 ft. away


    > Why not use a serial printer (Epson LX300+) and use the pause button on
    the
    > printer to do what you need to do. We easily got 500' with the right cable
    > and a Max232 on the source of the serial data.


    >
    >
    Original Message
    >
    > > Very sorry that I have not explained my situation very clear. In fact
    the
    > > other side is also a standard printing device. I need to send data from
    > the
    > > Stamp to that printing device from 300 ft. too. Because I need to add a
    > push
    > > button to the printing device such that when the button is pressed,
    Stamp
    > > get signal and sending data to printing device. For sending data from
    > stamp
    > > to printer, I have found a useful app note about SN75176 (RS485).
    However,
    > > how to handle the push button them?
    > >
    > > I don't know if it is possible to simply put 5V and ground and a press
    > > button to 300ft apart from the stamp. Should I use some sort of voltage
    > > up/down for transmitting the voltage signal for long distance? Or else
    > there
    > > is other better way to do the job.
    >
    >
    >
    >
    > 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.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-02-21 08:47
    Dear Gregory

    First of all, thanks for your advice. Could you elaborate more?

    Thanks for your help in advance.

    John


    Original Message
    From: "Gregory D Wagner" <gregory-wagner@u...>
    To: <basicstamps@yahoogroups.com>
    Sent: Wednesday, February 20, 2002 6:30 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Pushbutton of 300 ft. away


    > I'm not sure if I fully understand your question, but it sounds like a
    > 4-20mA current loop would work here. This is a standard for transmitting
    > signals long distances in noisy environments.
    > --
    > Greg
    >
    > John Leung wrote:
    > >I need to tight up a push button for Stamp II. That is not complicated
    since
    > >we just need to use a 5V to any pin via a 100K resistor, in between using
    an
    > >on / off switch to ground. The Stamp detect a LOW on pressing button.
    Stamp
    > >is nice with Button command for debounce key press.
    > >
    > >However, what about if I need to use the button from 300 feet away from
    the
    > >Stamp? Do I do the same as above? Should I use another stamp with RS485
    to
    > >connect the two stamps? Is there any simpler way to do it?
    > >
    > >Thanks for any advice.
    > >
    > >John Leung
    >
    >
    > 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.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
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