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Networking

ArchiverArchiver Posts: 46,084
edited 2003-06-29 07:40 in General Discussion
What is the Best way to hook up two or more stamps, and/or stamps to
other microcontrollers. I have hear about all the stuff of burning
out pins using serial commands... Basically, I want a stamp to be
dedicated to User I/O IE LCD, Key Board, Indicator lights and other
push buttons... The other Stamp will be dedicated to sensor
inputs...And then I will have a third Master Micro...Not sure which
yet.

Anyhow...Electronically, what is the best way to hook these up.

Thanks,
Eric

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-06-28 21:27
    Several issues to be addressed.
    There are so many different
    configurations you could use to hook up
    stamps, AND a stamp is single-threaded,
    so it has to wait for a connection.

    AND, a stamp pin can sink or source
    24 mA, which is quite a lot really,
    and if you have two drivers contending
    on the same line without some resistance
    in between, you do burn out pins.
    A simple 220 ohm resistor in series
    with the pin is enough to prevent this.

    AND, you probably want stamp A to
    initiate comm with Stamp B, and then
    allow Stamp B to initiate comm with
    Stamp A (also known as multiple
    masters)

    If it was me, and I had two stamps
    really close together (within 1 foot)
    I would use P12 and P13 (and a ground
    wire) to hook them
    up. I'd put a 220 ohm resistor in
    series on each stamp, to limit
    contention current to something
    non-destructive. Then I would
    designate one of them the
    master and one the slave.

    I would have the master periodically
    do a SEROUT, with flag pin and a
    timeout, to see if the slave had
    any data for me. I'd have the
    slave periodically doing SERIN,
    with flag pin and timeout, to
    look for data from the Master.

    That's what I'd do, but the Stamp
    is a very flexible beast, which
    gives you lots of other options.



    --- In basicstamps@yahoogroups.com, "Eric" <ESailer07@c...> wrote:
    > What is the Best way to hook up two or more stamps, and/or stamps
    to
    > other microcontrollers. I have hear about all the stuff of burning
    > out pins using serial commands... Basically, I want a stamp to be
    > dedicated to User I/O IE LCD, Key Board, Indicator lights and
    other
    > push buttons... The other Stamp will be dedicated to sensor
    > inputs...And then I will have a third Master Micro...Not sure which
    > yet.
    >
    > Anyhow...Electronically, what is the best way to hook these up.
    >
    > Thanks,
    > Eric
  • ArchiverArchiver Posts: 46,084
    edited 2003-06-28 21:57
    have a look at page 304 of the v2 stamp manual.
    i have 6 stamps hooked up like this and have never had a problem in the 2
    years the stamps
    have been yakking amongst themselves.

    ian

    Original Message
    From: Eric <ESailer07@c...>
    To: basicstamps@yahoogroups.com <basicstamps@yahoogroups.com>
    Date: Sunday, June 29, 2003 4:03 AM
    Subject: [noparse][[/noparse]basicstamps] Networking


    >What is the Best way to hook up two or more stamps, and/or stamps to
    >other microcontrollers. I have hear about all the stuff of burning
    >out pins using serial commands... Basically, I want a stamp to be
    >dedicated to User I/O IE LCD, Key Board, Indicator lights and other
    >push buttons... The other Stamp will be dedicated to sensor
    >inputs...And then I will have a third Master Micro...Not sure which
    >yet.
    >
    >Anyhow...Electronically, what is the best way to hook these up.
    >
    >Thanks,
    >Eric
    >
    >
    >
    >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 2003-06-28 23:09
    Excellent! I had forgotten about the 'open'
    baud modes. The 220 ohm series resistor can
    still be nice during development to save you
    from inadvertent shorts -- but you are
    absolutely right, if all nodes are properly
    'open baud moded', this works nicely.

    Have you used the 'flow pin' control with
    this? I'm curious if the 'FPin' also
    floats, and needs an external resistor
    in 'open baud' modes.

    --- In basicstamps@yahoogroups.com, "Ian Lawson" <irlawson@i...>
    wrote:
    > have a look at page 304 of the v2 stamp manual.
    > i have 6 stamps hooked up like this and have never had a problem in
    the 2
    > years the stamps
    > have been yakking amongst themselves.
    >
    > ian
    >
    >
    Original Message
    > From: Eric <ESailer07@c...>
    > To: basicstamps@yahoogroups.com <basicstamps@yahoogroups.com>
    > Date: Sunday, June 29, 2003 4:03 AM
    > Subject: [noparse][[/noparse]basicstamps] Networking
    >
    >
    > >What is the Best way to hook up two or more stamps, and/or stamps
    to
    > >other microcontrollers. I have hear about all the stuff of burning
    > >out pins using serial commands... Basically, I want a stamp to be
    > >dedicated to User I/O IE LCD, Key Board, Indicator lights and
    other
    > >push buttons... The other Stamp will be dedicated to sensor
    > >inputs...And then I will have a third Master Micro...Not sure which
    > >yet.
    > >
    > >Anyhow...Electronically, what is the best way to hook these up.
    > >
    > >Thanks,
    > >Eric
    > >
    > >
    > >
    > >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 2003-06-29 07:40
    hi allan
    i did allow for this in the circuit design
    but have never implemented it as it doesn't
    seem to be needed in my application.
    it seems you don't need a resistor on the fpin
    line just make sure they are all inputs.

    regards ian
    Original Message
    From: Allan Lane <allan.lane@h...>
    To: basicstamps@yahoogroups.com <basicstamps@yahoogroups.com>
    Date: Sunday, June 29, 2003 10:09 AM
    Subject: [noparse][[/noparse]basicstamps] Re: Networking


    >Excellent! I had forgotten about the 'open'
    >baud modes. The 220 ohm series resistor can
    >still be nice during development to save you
    >from inadvertent shorts -- but you are
    >absolutely right, if all nodes are properly
    >'open baud moded', this works nicely.
    >
    >Have you used the 'flow pin' control with
    >this? I'm curious if the 'FPin' also
    >floats, and needs an external resistor
    >in 'open baud' modes.
    >
    >--- In basicstamps@yahoogroups.com, "Ian Lawson" <irlawson@i...>
    >wrote:
    >> have a look at page 304 of the v2 stamp manual.
    >> i have 6 stamps hooked up like this and have never had a problem in
    >the 2
    >> years the stamps
    >> have been yakking amongst themselves.
    >>
    >> ian
    >>
    >>
    Original Message
    >> From: Eric <ESailer07@c...>
    >> To: basicstamps@yahoogroups.com <basicstamps@yahoogroups.com>
    >> Date: Sunday, June 29, 2003 4:03 AM
    >> Subject: [noparse][[/noparse]basicstamps] Networking
    >>
    >>
    >> >What is the Best way to hook up two or more stamps, and/or stamps
    >to
    >> >other microcontrollers. I have hear about all the stuff of burning
    >> >out pins using serial commands... Basically, I want a stamp to be
    >> >dedicated to User I/O IE LCD, Key Board, Indicator lights and
    >other
    >> >push buttons... The other Stamp will be dedicated to sensor
    >> >inputs...And then I will have a third Master Micro...Not sure which
    >> >yet.
    >> >
    >> >Anyhow...Electronically, what is the best way to hook these up.
    >> >
    >> >Thanks,
    >> >Eric
    >> >
    >> >
    >> >
    >> >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/
    >
    >
    >
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