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Dallas 1-wire

ArchiverArchiver Posts: 46,084
edited 2000-12-15 21:03 in General Discussion
Has anyone successfully gotten a BS2 to work with Dallas semi's 1-wire
network?

-
Ian Bobbitt
When an error occures:
A novice user blames himself,
a normal user blames the computer,
a power user sighs and gets another cup of coffee.

KB9VEX

ICQ: 14106680

It said requires windows 95 or better, so I installed Linux.

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2000-12-04 04:38
    In a message dated 12/3/00 7:24:26 PM Central Standard Time,
    bobbitti@b... writes:

    > Has anyone successfully gotten a BS2 to work with Dallas semi's 1-wire
    > network?

    The BS2p (coming mid January, 2001) has native 1-wire support (both bit and
    byte mode). The commands work just like SERIN and SEROUT -- except that
    they're called OWIN and OWOUT. The commands are very easy to use and don't
    require any hardware outside the Stamp except a 4.7K pullup and your 1-wire
    devices.
  • ArchiverArchiver Posts: 46,084
    edited 2000-12-14 06:17
    The BS2 can't communicate directly with a 1-wire device. Timing
    issues are the problem--the interpreter can't string together several
    discrete statements fast enough to meet the 1-wire time criteria.
    The BS2+ solves this problem by doing the 1-wire grunt work for you
    via a single command rather than as a series of commands. Also saves
    you an awful lot of code and code space in the process.

    The BS2+ with its 1-wire capability opens up a whole new array of
    nifty gadgets for your Stamp at minimal I/O pin cost. They're worth
    a look at http://www.dalsemi.com/products/autoinfo/1wire.html and
    http://www.dalsemi.com/products/autoinfo/touch.html. One of my
    favorites is the DS1921, a horse-pill sized gadget that I hauled down
    to the bottom of the Grand Canyon (and, fortunately, back up again)
    several weeks ago, then recovered temperature data stored therein
    covering several days upon my return.

    For those who may want to add a 1-wire capability to their existing
    Stamp (I've tested BS1 through BS2SX), I have developed and am using
    in my own gadgets an interface chip allowing communication with
    1-wire devices via SEROUT and SERIN statements. It makes using up
    to 10 1-wire devices at once very convenient for your Stamp and
    takes care of many of the unique 1-wire functions (such as SEARCH
    ROM, device selection, strong pullup control, alarm detection, etc.)
    for you. Let me know if interested.

    Steve

    On 14 Dec 00 at 19:55, givner@s... wrote:

    > I'm trying to get my Basic Stamp 2 to work with Dallas
    > Semiconductor's 1820 1-wire bus chip. I found a post in one of your
    > e-mail groups about this same problem. Someone responded to this
    > e-mail by saying that the BS2p has native 1-wire support. Does this
    > mean that the Basic Stamp 2 that I have does not have the
    > capabilitiy to interface with the DS 1820's 1-wire bus?...
  • ArchiverArchiver Posts: 46,084
    edited 2000-12-14 19:55
    I'm trying to get my Basic Stamp 2 to work with Dallas Semiconductor's
    1820 1-wire bus chip. I found a post in one of your e-mail groups
    about
    this same problem. Someone responded to this e-mail by saying that
    the
    BS2p has native 1-wire support. Does this mean that the Basic Stamp 2
    that I have does not have the capabilitiy to interface with the DS
    1820's 1-wire bus? If it does have the capability then I need help in
    designing a code to read the 64-bit ROM id of the DS1820. The code I
    have listed below prints the first 30 bits of the id in the debug
    window. The problem is that the bits all come out as zeroes which is
    wrong according to the people at Dallas Semiconductor. Please help me
    because I am presently at my wits end!
    WB con 4
    LCD con 9

    hold var byte 'work space for 1820 command.
    n var word 'variable timing word for DS1820

    write_1:
    PULSOUT WB,2 'the length of this and
    other
    pulses in the code
    INPUT WB 'are based on the
    DS1820
    data sheet info.
    PULSOUT LCD,20 'this command serves as a
    time
    holder.
    OUTPUT WB
    HIGH WB
    return

    write_0:
    PULSOUT WB,45
    PULSOUT LCD,13
    INPUT WB
    PULSOUT LCD,1
    OUTPUT WB
    HIGH WB
    return

    id:
    debug cls
    debug " please wait"
    pause 500
    debug cls
    OUTPUT WB 'send reset and presence pulses.
    HIGH WB
    PULSOUT WB,470
    INPUT WB
    pause 1 'wait for presence state to
    end.
    OUTPUT WB 'start sending a command.
    HIGH WB
    gosub write_1
    gosub write_1
    gosub write_0
    gosub write_0
    gosub write_1
    gosub write_1
    gosub write_0
    gosub write_0
    n = 0
    goto id_test1
    read_0:
    debug "0"
    OUTPUT WB
    HIGH WB
    n = n + 1
    goto id_test1
    read_1:
    debug "1"
    OUTPUT WB
    HIGH WB
    n = n + 1
    goto id_test1
    id_test1:
    pulsout WB,1
    INPUT WB
    IF n = 30 THEN yo
    IF WB = 1 THEN read_1
    goto read_0

    yo:
    OUTPUT WB 'send reset and presence
    pulses.
    HIGH WB
    PULSOUT WB,470
    INPUT WB
    PAUSE 1 'wait for presence
    state
    to end.
    OUTPUT WB 'end sending and receiving
    command process.
    HIGH WB
    pause 1000
    debug CLS
    debug "id confirmed"
    pause 1000





    If you have any questions about the code or can help me in any way,
    please e-mail me back at givner@s...
  • ArchiverArchiver Posts: 46,084
    edited 2000-12-15 20:31
    Personally I would wait for the BS2P in
    January which has native 1Wire support.
    It's going to save you a lot of time
    and code space!

    The Dec issue of Nuts and Volts has an
    article by Jon which gives some examples
    of using 1Wire with the BS2P, including
    a program that reads the DS1810 thermometer.

    It seems that some of the listings from
    this article are missing though - there
    is reference to a listing 2 which isn't
    in the magazine or on nutsvolts.com from
    what I can see.

    T
  • ArchiverArchiver Posts: 46,084
    edited 2000-12-15 21:03
    [font=arial,helvetica]In a message dated 12/15/00 2:56:42 PM Central Standard Time,
    analog8@home.com writes:

    Personally I would wait for the BS2P in
    January which has native 1Wire support.
    It's going to save you a lot of time
    and code space!



    And the BS2p is a joy to work with. ·It's really a great new Stamp.

    The Dec issue of Nuts and Volts has an
    article by Jon which gives some examples
    of using 1Wire with the BS2P, including
    a program that reads the DS1810 thermometer.

    It seems that some of the listings from
    this article are missing though - there
    is reference to a listing 2 which isn't
    in the magazine or on nutsvolts.com from
    what I can see.



    I noticed the missing listings too. ·Don't worry though, they will get posted
    at www.nutsvolts.com and also at www.parallaxinc.com in the very near future.

    -- Jon Williams
    -- Dallas, TX[/font]
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