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Watchdog on BS2? — Parallax Forums

Watchdog on BS2?

ArchiverArchiver Posts: 46,084
edited 2004-06-11 01:46 in General Discussion
Although I did not make the original post, It would be nice to have the
watchdog do what a watchdog does.....As you already know, if the watchdog timer
"times out" before being periodically reset by program instructions, cause the
program to start over from the beginning.

But on the other hand, the Stamps seem to be extremely robust and user error
in the code is about all I have seen make the program hang up...ie, never
ending loop.

my 2cents

Ken

======================
The watchdog inside the PIC or SX used in BASIC Stamp modules is not
accessible via PBASIC. Since you just learned about the watchdog, was
is it you'd like to do with it?

-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office


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

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-06-10 00:15
    I think for your application the watchdog would be nice but is not critical.
    For example if the weigh data stops working, the result is not catostrophic,
    it is?. A watchdog would indeed be needed (desired) if a micro controller was
    controlling some process where the result of the the micro no longer
    processing data would cause catostrophic event, like something catching on fire etc.

    On the other hand, in theory you could build a watchdog into your program
    using external hardware.

    My idea would be to use a re-triggerable one shot multivibrator. Have the
    stamp retrigger the multivibrator often enough to keep the output in one state,
    high or low.
    You would interface the high or low signal to the reset pin of the stamp
    (with a pull up on the stamp reset pin). Some trick would be needed to make sure
    the multivibrator does not hold the reset low while the stamp is attempting to
    "wake up" or start....that would not be to hard.

    If the stamp program stops running, the multivibrator times out and causes
    the reset pin on the stamp to go low, and resetting the program same as pusing
    the reset button.

    Jon Williams, in theory this should work, shouldn't it?

    Ken


    Recently I just finished my first commercial project using BS2.
    The project is to control Batching Plant and taking 2 serin from electronic
    scale for batch weigh data, but no watchdog.
    My friend said that when we use microcontroller for industrial process, it
    is vital to use watchdog.
    What I need to do is to apply watchdog in my project to monitor whenever my
    program hangs.
    If that happens, the watchdog will reset my program automatically.
    Also, what kind of conditions can make microcontroller to hang?

    Thanks,
    Bronson Alex


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-10 02:19
    How can I have Watchdog on my BS2?
    My friend said that the PIC controller on my BS2IC has 'built-in' watchdog, is that true? How can I access the watchdog?
    If it is not true, where should I start to learn more about watchdog?
    (I just knew the meaning of 'watchdog' yesterday).

    Regards,
    Bronson Alex

    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-10 02:28
    The watchdog inside the PIC or SX used in BASIC Stamp modules is not
    accessible via PBASIC. Since you just learned about the watchdog, was
    is it you'd like to do with it?

    -- Jon Williams
    -- Applications Engineer, Parallax
    -- Dallas Office


    Original Message
    From: ALTRAMAN [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=LQ5syy0G1okw5Yz1dBRC4FWKW1RHUP0YjfbqByKj9wZotUML0FIcmDWZHK9s6fmWVv78xb1lAiwnNXPLgWM]altraman@d...[/url
    Sent: Wednesday, June 09, 2004 8:19 PM
    To: basicstamps@yahoogroups.com
    Subject: [noparse][[/noparse]basicstamps] Watchdog on BS2?


    How can I have Watchdog on my BS2?
    My friend said that the PIC controller on my BS2IC has 'built-in'
    watchdog, is that true? How can I access the watchdog?
    If it is not true, where should I start to learn more about watchdog? (I
    just knew the meaning of 'watchdog' yesterday).

    Regards,
    Bronson Alex
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-10 02:45
    Recently I just finished my first commercial project using BS2.
    The project is to control Batching Plant and taking 2 serin from electronic
    scale for batch weigh data, but no watchdog.
    My friend said that when we use microcontroller for industrial process, it
    is vital to use watchdog.
    What I need to do is to apply watchdog in my project to monitor whenever my
    program hangs.
    If that happens, the watchdog will reset my program automatically.
    Also, what kind of conditions can make microcontroller to hang?

    Thanks,
    Bronson Alex

    Original Message
    From: "Jon Williams" <jwilliams@p...>
    To: <basicstamps@yahoogroups.com>
    Sent: Thursday, June 10, 2004 8:28 AM
    Subject: RE: [noparse][[/noparse]basicstamps] Watchdog on BS2?


    > The watchdog inside the PIC or SX used in BASIC Stamp modules is not
    > accessible via PBASIC. Since you just learned about the watchdog, was
    > is it you'd like to do with it?
    >
    > -- Jon Williams
    > -- Applications Engineer, Parallax
    > -- Dallas Office
    >
    >
    >
    Original Message
    > From: ALTRAMAN [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=djtv4mR1njCaJg3rhOVTyzvzD5AvjkI1ymIIKPN76sLnfHjig_4NVldA2MbQwg8Tx2kWuYE2cY6P6WA]altraman@d...[/url
    > Sent: Wednesday, June 09, 2004 8:19 PM
    > To: basicstamps@yahoogroups.com
    > Subject: [noparse][[/noparse]basicstamps] Watchdog on BS2?
    >
    >
    > How can I have Watchdog on my BS2?
    > My friend said that the PIC controller on my BS2IC has 'built-in'
    > watchdog, is that true? How can I access the watchdog?
    > If it is not true, where should I start to learn more about watchdog? (I
    > just knew the meaning of 'watchdog' yesterday).
    >
    > Regards,
    > Bronson Alex
    >
    >
    > 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
    >
    >
    >
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-10 04:10
    What you can do, then, is use an external one-shot (I have friend in
    England who loves the old 555 for this) that the BASIC Stamp will
    constantly reset. If your program gets stuck and doesn't get around to
    resetting the 555, its output can be used to reset the BASIC Stamp.

    What conditions will cause the micro to hang? Well, the BASIC Stamp has
    been around long enough that we're pretty certain it won't hang without
    your direct involvement, that is, a bad piece of code or code that waits
    on a input that never comes, etc.

    -- Jon Williams
    -- Applications Engineer, Parallax
    -- Dallas Office


    Original Message
    From: ALTRAMAN [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=OlyKXexMd7qaT22iqyQQnjvgO43Pi74oGSoqljza_1aapJbrtTIjv5Q-KUasAuYjK56J7kZKEhIBCLonPqQ]altraman@d...[/url
    Sent: Wednesday, June 09, 2004 8:46 PM
    To: basicstamps@yahoogroups.com
    Subject: Re: [noparse][[/noparse]basicstamps] Watchdog on BS2?


    Recently I just finished my first commercial project using BS2. The
    project is to control Batching Plant and taking 2 serin from electronic
    scale for batch weigh data, but no watchdog. My friend said that when we
    use microcontroller for industrial process, it is vital to use watchdog.
    What I need to do is to apply watchdog in my project to monitor whenever
    my program hangs. If that happens, the watchdog will reset my program
    automatically. Also, what kind of conditions can make microcontroller to
    hang?

    Thanks,
    Bronson Alex

    Original Message
    From: "Jon Williams" <jwilliams@p...>
    To: <basicstamps@yahoogroups.com>
    Sent: Thursday, June 10, 2004 8:28 AM
    Subject: RE: [noparse][[/noparse]basicstamps] Watchdog on BS2?


    > The watchdog inside the PIC or SX used in BASIC Stamp modules is not
    > accessible via PBASIC. Since you just learned about the watchdog, was

    > is it you'd like to do with it?
    >
    > -- Jon Williams
    > -- Applications Engineer, Parallax
    > -- Dallas Office
    >
    >
    >
    Original Message
    > From: ALTRAMAN [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=OlyKXexMd7qaT22iqyQQnjvgO43Pi74oGSoqljza_1aapJbrtTIjv5Q-KUasAuYjK56J7kZKEhIBCLonPqQ]altraman@d...[/url
    > Sent: Wednesday, June 09, 2004 8:19 PM
    > To: basicstamps@yahoogroups.com
    > Subject: [noparse][[/noparse]basicstamps] Watchdog on BS2?
    >
    >
    > How can I have Watchdog on my BS2?
    > My friend said that the PIC controller on my BS2IC has 'built-in'
    > watchdog, is that true? How can I access the watchdog? If it is not
    > true, where should I start to learn more about watchdog? (I just knew
    > the meaning of 'watchdog' yesterday).
    >
    > Regards,
    > Bronson Alex
    >
    >
    > 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
    >
    >
    >
    >
    >
    >
    >



    To UNSUBSCRIBE, just send mail to:
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  • ArchiverArchiver Posts: 46,084
    edited 2004-06-10 04:29
    HeHeHe .. guess the ole saying is true. great minds think alike ..LoL

    must admit using a 555 as an auto-reset or watchdog is a pretty good idea.
    Another use for it is a auto-power off feature to kill power after so long
    without no activity


    At 10:15 PM 6/9/2004, you wrote:
    >I think for your application the watchdog would be nice but is not critical.
    >For example if the weigh data stops working, the result is not catostrophic,
    >it is?. A watchdog would indeed be needed (desired) if a micro controller was
    >controlling some process where the result of the the micro no longer
    >processing data would cause catostrophic event, like something catching on
    >fire etc.
    >
    >On the other hand, in theory you could build a watchdog into your program
    >using external hardware.
    >
    >My idea would be to use a re-triggerable one shot multivibrator. Have the
    >stamp retrigger the multivibrator often enough to keep the output in one
    >state,
    >high or low.
    >You would interface the high or low signal to the reset pin of the stamp
    >(with a pull up on the stamp reset pin). Some trick would be needed to
    >make sure
    >the multivibrator does not hold the reset low while the stamp is
    >attempting to
    >"wake up" or start....that would not be to hard.
    >
    >If the stamp program stops running, the multivibrator times out and causes
    >the reset pin on the stamp to go low, and resetting the program same as
    >pusing
    >the reset button.
    >
    >Jon Williams, in theory this should work, shouldn't it?
    >
    >Ken
    >
    >
    >
    >Recently I just finished my first commercial project using BS2.
    >The project is to control Batching Plant and taking 2 serin from electronic
    >scale for batch weigh data, but no watchdog.
    >My friend said that when we use microcontroller for industrial process, it
    >is vital to use watchdog.
    >What I need to do is to apply watchdog in my project to monitor whenever my
    >program hangs.
    >If that happens, the watchdog will reset my program automatically.
    >Also, what kind of conditions can make microcontroller to hang?
    >
    >Thanks,
    >Bronson Alex
    >
    >
    >[noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    >
    >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
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-11 01:46
    Thanks to all responders.
    I will try to use 555 to implement watchdog in my application.

    Bronson Alex

    Original Message
    From: <smartdim@a...>
    To: <basicstamps@yahoogroups.com>
    Sent: Thursday, June 10, 2004 10:15 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Watchdog on BS2?


    > I think for your application the watchdog would be nice but is not
    critical.
    > For example if the weigh data stops working, the result is not
    catostrophic,
    > it is?. A watchdog would indeed be needed (desired) if a micro controller
    was
    > controlling some process where the result of the the micro no longer
    > processing data would cause catostrophic event, like something catching on
    fire etc.
    >
    > On the other hand, in theory you could build a watchdog into your program
    > using external hardware.
    >
    > My idea would be to use a re-triggerable one shot multivibrator. Have the
    > stamp retrigger the multivibrator often enough to keep the output in one
    state,
    > high or low.
    > You would interface the high or low signal to the reset pin of the stamp
    > (with a pull up on the stamp reset pin). Some trick would be needed to
    make sure
    > the multivibrator does not hold the reset low while the stamp is
    attempting to
    > "wake up" or start....that would not be to hard.
    >
    > If the stamp program stops running, the multivibrator times out and causes
    > the reset pin on the stamp to go low, and resetting the program same as
    pusing
    > the reset button.
    >
    > Jon Williams, in theory this should work, shouldn't it?
    >
    > Ken
    >
    >
    >
    > Recently I just finished my first commercial project using BS2.
    > The project is to control Batching Plant and taking 2 serin from
    electronic
    > scale for batch weigh data, but no watchdog.
    > My friend said that when we use microcontroller for industrial process, it
    > is vital to use watchdog.
    > What I need to do is to apply watchdog in my project to monitor whenever
    my
    > program hangs.
    > If that happens, the watchdog will reset my program automatically.
    > Also, what kind of conditions can make microcontroller to hang?
    >
    > Thanks,
    > Bronson Alex
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    >
    > 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
    >
    >
    >
    >
    >
    >
    >
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