Shop OBEX P1 Docs P2 Docs Learn Events
BS1 Hiccup — Parallax Forums

BS1 Hiccup

ArchiverArchiver Posts: 46,084
edited 2002-03-13 12:32 in General Discussion
I'm using a BS1 to latch and unlatch a door. The stamp is connected
to two relays using 10K resistors and 2N2222 transistors (through pin4
to latch and pin5 to unlatch). The relays are 12V, capable of 5A and
are used to switch power to an electric motor (3A max) that latches
and unlatches a door. Two more pins are used to turn off the motor
once enough travel has occured (pin3 when latched and pin2 when
unlatched). The respective pins are made high (+5 from an external
source) when a microswitch closes. Finally pin7 is connected to a
microswitch that calls for latch when high and unlatch when low. The
relays are powered from a car battery, and the stamp is powered from a
+5 volt power supply, with all grounds together.

The program runs fine, except it randomly starts over! The stamp
seems to hiccup when the relays open or sometimes when the relays
close. But it doesn't happen all the time. Everything might work
perfectly for 5 or 6 latches and unlatches and then the hiccup might
occur 3 or 4 times in a row where the stamp just seems to reset itself
and start over at the top (the pause 2000 is inserted so I can tell
when this occurs). It might even do this a few times in a row before
normal program execution continues.

What could be causing this?

pause 2000

loop:
low 4
low 5
if pin7=1 then latch
if pin7=0 then unlatch
goto loop

latch:
if pin3=1 then loop
high 4
goto latch

unlatch:
if pin2=1 then loop
high 5
goto unlatch

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2002-03-10 14:08
    This isn't that unusual. The relay coils are causing a reset. A few
    things to do.

    1) If possible, isolate the relay power from the Stamp power. Have a
    common ground in any event and make that ground as solid as possible
    (not very thin wire).

    2) Put a large capacitor on the Stamp's 5V bus. This will slow its start
    up, but will also give it some extra time when the power browns out.
    Try, say, 1000uF between 5V and ground as close to the Stamp as is
    practical.

    3) If noise coupling might be a problem, considering holding the reset
    line to 5V through a low value pull up (4.7K) instead of relying on the
    Stamp to do it.

    There is an article about this in the Stamp FAQ at
    http://www.al-williams.com/wd5gnr/stampfaq.htm if you want to read more
    about it.

    Good luck!

    Al Williams
    AWC
    * Floating point A/D
    http://www.al-williams.com/awce/pak9.htm



    >
    Original Message
    > From: bdespins [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=rqXnEiDhjGUyJSX7BbCs1Th3M1sIXhMYzNOoZI3fHm5HgBkKcoKpCKE7-F3TVjPGGi-qCkZyCOIfgp5QspE]bdespins@t...[/url
    > Sent: Sunday, March 10, 2002 8:02 AM
    > To: basicstamps@yahoogroups.com
    > Subject: [noparse][[/noparse]basicstamps] BS1 Hiccup
    >
    >
    > I'm using a BS1 to latch and unlatch a door. The stamp is connected
    > to two relays using 10K resistors and 2N2222 transistors
    > (through pin4
    > to latch and pin5 to unlatch). The relays are 12V, capable of 5A and
    > are used to switch power to an electric motor (3A max) that latches
    > and unlatches a door. Two more pins are used to turn off the motor
    > once enough travel has occured (pin3 when latched and pin2 when
    > unlatched). The respective pins are made high (+5 from an external
    > source) when a microswitch closes. Finally pin7 is connected to a
    > microswitch that calls for latch when high and unlatch when low. The
    > relays are powered from a car battery, and the stamp is
    > powered from a
    > +5 volt power supply, with all grounds together.
    >
    > The program runs fine, except it randomly starts over! The stamp
    > seems to hiccup when the relays open or sometimes when the relays
    > close. But it doesn't happen all the time. Everything might work
    > perfectly for 5 or 6 latches and unlatches and then the hiccup might
    > occur 3 or 4 times in a row where the stamp just seems to
    > reset itself
    > and start over at the top (the pause 2000 is inserted so I can tell
    > when this occurs). It might even do this a few times in a row before
    > normal program execution continues.
    >
    > What could be causing this?
    >
    > pause 2000
    >
    > loop:
    > low 4
    > low 5
    > if pin7=1 then latch
    > if pin7=0 then unlatch
    > goto loop
    >
    > latch:
    > if pin3=1 then loop
    > high 4
    > goto latch
    >
    > unlatch:
    > if pin2=1 then loop
    > high 5
    > goto unlatch
    >
    >
    > 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 2002-03-10 14:35
    At 02:01 PM 3/10/2002 +0000, you wrote:
    >I'm using a BS1 to latch and unlatch a door. The stamp is connected
    >to two relays using 10K resistors and 2N2222 transistors (through pin4
    >to latch and pin5 to unlatch). The relays are 12V, capable of 5A and
    >are used to switch power to an electric motor (3A max) that latches
    >and unlatches a door. Two more pins are used to turn off the motor
    >once enough travel has occured (pin3 when latched and pin2 when
    >unlatched). The respective pins are made high (+5 from an external
    >source) when a microswitch closes. Finally pin7 is connected to a
    >microswitch that calls for latch when high and unlatch when low. The
    >relays are powered from a car battery, and the stamp is powered from a
    >+5 volt power supply, with all grounds together.
    Hi ??? -

    Just a few thoughts -

    Which pin are you using to power the Stamp, Pin 1 or Pin 5 ?
    If Pin 1 is being used the MINIMUM ACCEPTABLE voltage is 5.5 VDC.

    Is there any possibility the motor is drawing excess current at
    end-of-travel ? Ergo it's not being shut down soon enough. If so, this
    might cause a dip in the supplied power, causing the Stamp to reset.

    Which power source is being used for Pin 7 ?

    Regardless of how you have the circuit described, have you ever seen
    BOTH relays engaged at the same time ?

    Regards,

    Bruce Bates
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-10 15:00
    You need to check the state of your batteries and possibly provide some
    filtering for the power going to the BS1 -- maybe a 0.1 mfd and 220 mfd
    capacitor across the power input of the Stamp. If you are using an external
    voltage regulator to power the Stamp, consider using some filtering as
    specified by the regulator documentation.

    Try running the Stamp off a 9v battery and see what happens.

    Original Message


    > I'm using a BS1 to latch and unlatch a door. The stamp is connected
    > to two relays using 10K resistors and 2N2222 transistors (through pin4
    > to latch and pin5 to unlatch). The relays are 12V, capable of 5A and
    > are used to switch power to an electric motor (3A max) that latches
    > and unlatches a door. Two more pins are used to turn off the motor
    > once enough travel has occured (pin3 when latched and pin2 when
    > unlatched). The respective pins are made high (+5 from an external
    > source) when a microswitch closes. Finally pin7 is connected to a
    > microswitch that calls for latch when high and unlatch when low. The
    > relays are powered from a car battery, and the stamp is powered from a
    > +5 volt power supply, with all grounds together.
    >
    > The program runs fine, except it randomly starts over! The stamp
    > seems to hiccup when the relays open or sometimes when the relays
    > close. But it doesn't happen all the time. Everything might work
    > perfectly for 5 or 6 latches and unlatches and then the hiccup might
    > occur 3 or 4 times in a row where the stamp just seems to reset itself
    > and start over at the top (the pause 2000 is inserted so I can tell
    > when this occurs). It might even do this a few times in a row before
    > normal program execution continues.
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-10 19:53
    also try some software debounce on your inputs.
    if all fails try some opto isolators on the inputs.
    regards
    victor
    Original Message
    From: Al Williams <alw@a...>
    To: basicstamps@yahoogroups.com <basicstamps@yahoogroups.com>
    Date: Sunday, March 10, 2002 9:09 AM
    Subject: RE: [noparse][[/noparse]basicstamps] BS1 Hiccup


    >This isn't that unusual. The relay coils are causing a reset. A few
    >things to do.
    >
    >1) If possible, isolate the relay power from the Stamp power. Have a
    >common ground in any event and make that ground as solid as possible
    >(not very thin wire).
    >
    >2) Put a large capacitor on the Stamp's 5V bus. This will slow its start
    >up, but will also give it some extra time when the power browns out.
    >Try, say, 1000uF between 5V and ground as close to the Stamp as is
    >practical.
    >
    >3) If noise coupling might be a problem, considering holding the reset
    >line to 5V through a low value pull up (4.7K) instead of relying on the
    >Stamp to do it.
    >
    >There is an article about this in the Stamp FAQ at
    >http://www.al-williams.com/wd5gnr/stampfaq.htm if you want to read more
    >about it.
    >
    >Good luck!
    >
    >Al Williams
    >AWC
    >* Floating point A/D
    >http://www.al-williams.com/awce/pak9.htm
    >
    >
    >
    >>
    Original Message
    >> From: bdespins [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=M09bhrsJPWeLlcgF3qRPMzLimKAJNMGG_PVyOmxS-f6sw9qcrhfpJsKnnl_uQx_TiVFXzhJfJs2tnwq4S0ZRcg]bdespins@t...[/url
    >> Sent: Sunday, March 10, 2002 8:02 AM
    >> To: basicstamps@yahoogroups.com
    >> Subject: [noparse][[/noparse]basicstamps] BS1 Hiccup
    >>
    >>
    >> I'm using a BS1 to latch and unlatch a door. The stamp is connected
    >> to two relays using 10K resistors and 2N2222 transistors
    >> (through pin4
    >> to latch and pin5 to unlatch). The relays are 12V, capable of 5A and
    >> are used to switch power to an electric motor (3A max) that latches
    >> and unlatches a door. Two more pins are used to turn off the motor
    >> once enough travel has occured (pin3 when latched and pin2 when
    >> unlatched). The respective pins are made high (+5 from an external
    >> source) when a microswitch closes. Finally pin7 is connected to a
    >> microswitch that calls for latch when high and unlatch when low. The
    >> relays are powered from a car battery, and the stamp is
    >> powered from a
    >> +5 volt power supply, with all grounds together.
    >>
    >> The program runs fine, except it randomly starts over! The stamp
    >> seems to hiccup when the relays open or sometimes when the relays
    >> close. But it doesn't happen all the time. Everything might work
    >> perfectly for 5 or 6 latches and unlatches and then the hiccup might
    >> occur 3 or 4 times in a row where the stamp just seems to
    >> reset itself
    >> and start over at the top (the pause 2000 is inserted so I can tell
    >> when this occurs). It might even do this a few times in a row before
    >> normal program execution continues.
    >>
    >> What could be causing this?
    >>
    >> pause 2000
    >>
    >> loop:
    >> low 4
    >> low 5
    >> if pin7=1 then latch
    >> if pin7=0 then unlatch
    >> goto loop
    >>
    >> latch:
    >> if pin3=1 then loop
    >> high 4
    >> goto latch
    >>
    >> unlatch:
    >> if pin2=1 then loop
    >> high 5
    >> goto unlatch
    >>
    >>
    >> 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/
    >
    >
    >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 2002-03-12 05:22
    Thanks to all who suggested fixes for my hiccuping stamp.
    Unfortunately none of the suggestions improved the Stamp randomly
    resetting. I've decided to go with an H-bridge to control the motor
    instead of relays.

    Thanks again.

    Bernard Despins
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-12 05:39
    I must have missed this one, but did anyone check that you have a diode
    across each relay coil to kill any back emf? Back emf will cause a random
    reset. I know, because I've seen it happen every time there's been a relay
    with no doide across the coil.

    A 1N4007 will do the trick (Anode towards V+, Cathode towards ground side of
    the coil).

    Cheers,

    Ben.

    --
    http://www.lennard.net.nz/
    Ben Lennard, NCEE, Dip EE

    Web Hosting and Electronics R&D
    Club Coordinator, Victoria University of Wellington Hockey Club

    Hm: +64 4 972 7567
    Mb: +64 21 536 627
    87 Spencer Street
    Crofton Downs
    Wellington
    New Zealand

    "To the optimist, the glass is half full. To the pessimist, the glass is
    half empty. To the engineer, the glass is twice as big as it needs to be."

    No animals were harmed in the transmission of this email, although the
    Dog next door is living on borrowed time, let me tell you! Those of you
    with an overwhelming fear of the unknown will be gratified to learn that
    there is no hidden message revealed by reading this warning backwards.




    From: "bdespins" <bdespins@t...>
    To: basicstamps@yahoogroups.com
    Subject: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    Date: Tue, 12 Mar 2002 6:22 PM


    Thanks to all who suggested fixes for my hiccuping stamp.
    Unfortunately none of the suggestions improved the Stamp randomly
    resetting. I've decided to go with an H-bridge to control the motor
    instead of relays.

    Thanks again.

    Bernard Despins


    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/





    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-12 12:14
    Sorry for butting in, but I think you should orient the diode with the cathode
    twd.
    the V+.
    Russ


    Original Message
    From: "Ben Lennard" <postmaster@s...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, March 12, 2002 12:39 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup


    | I must have missed this one, but did anyone check that you have a diode
    | across each relay coil to kill any back emf? Back emf will cause a random
    | reset. I know, because I've seen it happen every time there's been a relay
    | with no doide across the coil.
    |
    | A 1N4007 will do the trick (Anode towards V+, Cathode towards ground side of
    | the coil).
    |
    | Cheers,
    |
    | Ben.
    |
    | --
    | http://www.lennard.net.nz/
    | Ben Lennard, NCEE, Dip EE
    |
    | Web Hosting and Electronics R&D
    | Club Coordinator, Victoria University of Wellington Hockey Club
    |
    | Hm: +64 4 972 7567
    | Mb: +64 21 536 627
    | 87 Spencer Street
    | Crofton Downs
    | Wellington
    | New Zealand
    |
    | "To the optimist, the glass is half full. To the pessimist, the glass is
    | half empty. To the engineer, the glass is twice as big as it needs to be."
    |
    | No animals were harmed in the transmission of this email, although the
    | Dog next door is living on borrowed time, let me tell you! Those of you
    | with an overwhelming fear of the unknown will be gratified to learn that
    | there is no hidden message revealed by reading this warning backwards.
    |
    |
    |
    |
    |
    | From: "bdespins" <bdespins@t...>
    | To: basicstamps@yahoogroups.com
    | Subject: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    | Date: Tue, 12 Mar 2002 6:22 PM
    |
    |
    | Thanks to all who suggested fixes for my hiccuping stamp.
    | Unfortunately none of the suggestions improved the Stamp randomly
    | resetting. I've decided to go with an H-bridge to control the motor
    | instead of relays.
    |
    | Thanks again.
    |
    | Bernard Despins
    |
    |
    | 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/
    |
    |
    |
    |
    |
    | [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.
    |
    |
    | Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    |
    |
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-13 05:32
    --- In basicstamps@y..., "Ben Lennard" <postmaster@s...> wrote:
    > I must have missed this one, but did anyone check that you have a
    diode
    > across each relay coil to kill any back emf? Back emf will cause a
    random
    > reset. I know, because I've seen it happen every time there's been
    a relay
    > with no doide across the coil.

    Yes I have diodes across the relays. I've tried everything from
    de-bouncing my inputs (first thing I tried until I realized the stamp
    was actually resetting). Tried holding the reset pin high, tried
    putting a large capacitor on the stamp's power supply, tried powering
    the stamp with a 9V battery instead of the 12V car battery powering
    the relays or the +5V regulator that is powering the microswitches.
    Tried using a different stamp. I spent two days trying anything and
    everything. I finally gave up and I'm going for an H-bridge. I
    considered optoisolators, but since that involves a redesign anyway,
    I'm going to get rid of the relays and I'm going to step up to a BS2
    industrial version so that the setup will operate over a wider range
    of temperatures.

    Bernard Despins
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-13 09:40
    Oops!

    Hehe, you're right, and that's always the way to do it, as in my circuits.

    I just got the names wrong. For those who, like me, can get the names
    wrong, let's try it this way:

    The end of the diode with the band around it goes towards +V (that is the
    Cathode - NOT Anode, as I accidentally said before).

    Cheers, and well spotted Russ!

    Ben, in Windy Wellington, New Zealand.

    --
    http://www.lennard.net.nz/
    Ben Lennard, NCEE, Dip EE

    Web Hosting and Electronics R&D
    Club Coordinator, Victoria University of Wellington Hockey Club

    Hm: +64 4 972 7567
    Mb: +64 21 536 627
    87 Spencer Street
    Crofton Downs
    Wellington
    New Zealand

    "To the optimist, the glass is half full. To the pessimist, the glass is
    half empty. To the engineer, the glass is twice as big as it needs to be."

    No animals were harmed in the transmission of this email, although the
    Dog next door is living on borrowed time, let me tell you! Those of you
    with an overwhelming fear of the unknown will be gratified to learn that
    there is no hidden message revealed by reading this warning backwards.




    From: "Russ Bassani" <RussBassani@a...>
    To: <basicstamps@yahoogroups.com>
    Subject: Re: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    Date: Wed, 13 Mar 2002 1:14 AM


    Sorry for butting in, but I think you should orient the diode with the
    cathode twd.
    the V+.
    Russ


    Original Message
    From: "Ben Lennard" <postmaster@s...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, March 12, 2002 12:39 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup


    | I must have missed this one, but did anyone check that you have a diode
    | across each relay coil to kill any back emf? Back emf will cause a random
    | reset. I know, because I've seen it happen every time there's been a
    relay
    | with no doide across the coil.
    |
    | A 1N4007 will do the trick (Anode towards V+, Cathode towards ground side
    of
    | the coil).
    |
    | Cheers,
    |
    | Ben.
    |
    | --
    | http://www.lennard.net.nz/
    | Ben Lennard, NCEE, Dip EE
    |
    | Web Hosting and Electronics R&D
    | Club Coordinator, Victoria University of Wellington Hockey Club
    |
    | Hm: +64 4 972 7567
    | Mb: +64 21 536 627
    | 87 Spencer Street
    | Crofton Downs
    | Wellington
    | New Zealand
    |
    | "To the optimist, the glass is half full. To the pessimist, the glass is
    | half empty. To the engineer, the glass is twice as big as it needs to
    be."
    |
    | No animals were harmed in the transmission of this email, although the
    | Dog next door is living on borrowed time, let me tell you! Those of you
    | with an overwhelming fear of the unknown will be gratified to learn that
    | there is no hidden message revealed by reading this warning backwards.
    |
    |
    |
    |
    |
    | From: "bdespins" <bdespins@t...>
    | To: basicstamps@yahoogroups.com
    | Subject: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    | Date: Tue, 12 Mar 2002 6:22 PM
    |
    |
    | Thanks to all who suggested fixes for my hiccuping stamp.
    | Unfortunately none of the suggestions improved the Stamp randomly
    | resetting. I've decided to go with an H-bridge to control the motor
    | instead of relays.
    |
    | Thanks again.
    |
    | Bernard Despins
    |
    |
    | 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/
    |
    |
    |
    |
    |
    | [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.
    |
    |
    | Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    |
    |


    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/





    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2002-03-13 12:32
    Glad to have helped.
    The way my memory is these days, I was lucky to
    remember what a diode was.
    regards
    Russ


    Original Message
    From: "Ben Lennard" <postmaster@s...>
    To: <basicstamps@yahoogroups.com>
    Sent: Wednesday, March 13, 2002 4:40 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup


    | Oops!
    |
    | Hehe, you're right, and that's always the way to do it, as in my circuits.
    |
    | I just got the names wrong. For those who, like me, can get the names
    | wrong, let's try it this way:
    |
    | The end of the diode with the band around it goes towards +V (that is the
    | Cathode - NOT Anode, as I accidentally said before).
    |
    | Cheers, and well spotted Russ!
    |
    | Ben, in Windy Wellington, New Zealand.
    |
    | --
    | http://www.lennard.net.nz/
    | Ben Lennard, NCEE, Dip EE
    |
    | Web Hosting and Electronics R&D
    | Club Coordinator, Victoria University of Wellington Hockey Club
    |
    | Hm: +64 4 972 7567
    | Mb: +64 21 536 627
    | 87 Spencer Street
    | Crofton Downs
    | Wellington
    | New Zealand
    |
    | "To the optimist, the glass is half full. To the pessimist, the glass is
    | half empty. To the engineer, the glass is twice as big as it needs to be."
    |
    | No animals were harmed in the transmission of this email, although the
    | Dog next door is living on borrowed time, let me tell you! Those of you
    | with an overwhelming fear of the unknown will be gratified to learn that
    | there is no hidden message revealed by reading this warning backwards.
    |
    |
    |
    |
    |
    | From: "Russ Bassani" <RussBassani@a...>
    | To: <basicstamps@yahoogroups.com>
    | Subject: Re: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    | Date: Wed, 13 Mar 2002 1:14 AM
    |
    |
    | Sorry for butting in, but I think you should orient the diode with the
    | cathode twd.
    | the V+.
    | Russ
    |
    |
    |
    Original Message
    | From: "Ben Lennard" <postmaster@s...>
    | To: <basicstamps@yahoogroups.com>
    | Sent: Tuesday, March 12, 2002 12:39 AM
    | Subject: Re: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    |
    |
    | | I must have missed this one, but did anyone check that you have a diode
    | | across each relay coil to kill any back emf? Back emf will cause a random
    | | reset. I know, because I've seen it happen every time there's been a
    | relay
    | | with no doide across the coil.
    | |
    | | A 1N4007 will do the trick (Anode towards V+, Cathode towards ground side
    | of
    | | the coil).
    | |
    | | Cheers,
    | |
    | | Ben.
    | |
    | | --
    | | http://www.lennard.net.nz/
    | | Ben Lennard, NCEE, Dip EE
    | |
    | | Web Hosting and Electronics R&D
    | | Club Coordinator, Victoria University of Wellington Hockey Club
    | |
    | | Hm: +64 4 972 7567
    | | Mb: +64 21 536 627
    | | 87 Spencer Street
    | | Crofton Downs
    | | Wellington
    | | New Zealand
    | |
    | | "To the optimist, the glass is half full. To the pessimist, the glass is
    | | half empty. To the engineer, the glass is twice as big as it needs to
    | be."
    | |
    | | No animals were harmed in the transmission of this email, although the
    | | Dog next door is living on borrowed time, let me tell you! Those of you
    | | with an overwhelming fear of the unknown will be gratified to learn that
    | | there is no hidden message revealed by reading this warning backwards.
    | |
    | |
    | |
    | |
    | |
    | | From: "bdespins" <bdespins@t...>
    | | To: basicstamps@yahoogroups.com
    | | Subject: [noparse][[/noparse]basicstamps] Re: BS1 Hiccup
    | | Date: Tue, 12 Mar 2002 6:22 PM
    | |
    | |
    | | Thanks to all who suggested fixes for my hiccuping stamp.
    | | Unfortunately none of the suggestions improved the Stamp randomly
    | | resetting. I've decided to go with an H-bridge to control the motor
    | | instead of relays.
    | |
    | | Thanks again.
    | |
    | | Bernard Despins
    | |
    | |
    | | 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/
    | |
    | |
    | |
    | |
    | |
    | | [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.
    | |
    | |
    | | Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    | |
    | |
    |
    |
    | 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/
    |
    |
    |
    |
    |
    | [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.
    |
    |
    | Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    |
    |
Sign In or Register to comment.