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serial cable

ArchiverArchiver Posts: 46,084
edited 2004-02-11 21:24 in General Discussion
Hi

If I understand you right, you say that you use the shield of your
cable for GND (signal and protective). With the long 200ft cable in
mind, I would use a separate wire (inside the shield) for signal GND
and leave the shield for protective GND. Don't use the shield for
signal GND in a noisy environment.
Appart from that, I think using caps is a good idea - look at
http://www.emesystems.com/BS2rs232.htm#resets
for a circuit diagram.

hope this helps
Adrian

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-01-17 17:08
    I have a stamp sending data to a PC in a noisy industrial environment. Inside
    the cable I am using 4 wires, serial in, serial out, ATN and ground which is
    the shield. I also have a jumper on the ATN line so the PC will not reset the
    stamp when it is shut down. I am getting spuratic events when plugging and
    unplugging the cable, like lock ups and resets. The ground on the stamp side is
    not an earth ground, just a dc ground on the board which is not earth grounded
    either. What is the preferred method for making this connection or cable? It
    would be an earth ground on the PC side of the cable. Would caps or resistors
    help in any way? Oh the cable is about 200ft long. I know this seems long but
    the data gets there flawlessly. It never misses a beat. Thanks in advance!


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-01-17 17:17
    --- In basicstamps@yahoogroups.com, "Ricky Konvicka" <ricky@m...>
    wrote:
    > I have a stamp sending data to a PC in a noisy industrial
    environment. Inside the cable I am using 4 wires, serial in, serial
    out, ATN and ground which is the shield. I also have a jumper on
    the ATN line so the PC will not reset the stamp when it is shut
    down. I am getting spuratic events when plugging and unplugging the
    cable, like lock ups and resets. The ground on the stamp side is not
    an earth ground, just a dc ground on the board which is not earth
    grounded either. What is the preferred method for making this
    connection or cable? It would be an earth ground on the PC side of
    the cable. Would caps or resistors help in any way? Oh the cable is
    about 200ft long. I know this seems long but the data gets there
    flawlessly. It never misses a beat. Thanks in advance!
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]

    If I read this right, I intrepret that you have a 3-
    conductor,shielded cable. Also. you state that the stamp gound is
    just VSS and not tied to earth ground and that the shield of the
    cable is tied to the stamp VSS. I would try a 4-conductor,shielded
    cable and tie the shield of the cable to the chassis ground/frame of
    the PC.

    --Guy
  • ArchiverArchiver Posts: 46,084
    edited 2003-01-17 23:31
    Hi,
    200 feet may be OK without noise but it may still be marginal.
    Try a Ferrite Core on each end. If this doesn't work then the safest thing to
    do is use a Short Haul Modem. I use them on my Industrial CNC machines. The
    noise can kill the PC Serial port (Expensive$) or even destroy the serial
    port in the CNC (Very Expensive$$$) The other thing to think about is
    Lightning. The Steel trusses used in many factory roofs make good conductors
    of Lightning Strikes. I repaired a customers system last year. The Lightning
    struck a far end of the building, but totally fries the PC on one end and did
    $5,000 damage to the CNC (In our case the CNC is the Stamp).

    The Short Haul Modems use opto-isolators for safety and Current Loop between
    modems for Data Integrity.
    Wire systems are cheaper, but the fiber system is much better.
    A 200 foot fiber system will cost less than $1,000. Much cheaper than repair
    bills, and don't forget down time does cost you money.

    Look to <A HREF="www.blackbox.com">www.blackbox.com</A>

    Alan Bradford
    Plasma Technologies


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-01-18 23:13
    I agree with what the other guys have said, don't run your shield as the
    ground for the stamp.

    Depending on what you have available to you for wire, I suggest you use two
    individual runs of TWISTED shielded twin.

    Do NOT ground the shields at both ends. Ground at computer end only.

    If these don't work, why not consider an FRO link?


    For more information on data cabling, try a google search on CSDB
    (commercial standard data bus). The info that you will find on such a search
    will be aircraft databus standard wiring, which typically is long low speed
    databus runs in electrically noisy environments.

    Regards,


    Dwain
    Original Message
    From: "Ricky Konvicka" <ricky@m...>
    To: <basicstamps@yahoogroups.com>
    Sent: Saturday, January 18, 2003 4:08 AM
    Subject: [noparse][[/noparse]basicstamps] serial cable


    > I have a stamp sending data to a PC in a noisy industrial environment.
    Inside the cable I am using 4 wires, serial in, serial out, ATN and ground
    which is the shield. I also have a jumper on the ATN line so the PC will
    not reset the stamp when it is shut down. I am getting spuratic events when
    plugging and unplugging the cable, like lock ups and resets. The ground on
    the stamp side is not an earth ground, just a dc ground on the board which
    is not earth grounded either. What is the preferred method for making this
    connection or cable? It would be an earth ground on the PC side of the
    cable. Would caps or resistors help in any way? Oh the cable is about
    200ft long. I know this seems long but the data gets there flawlessly. It
    never misses a beat. Thanks in advance!
    >
    >
    > [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 2003-01-19 00:13
    I've had good luck with low-cost 4-conductor SVHS cable, which consists
    of a pair on inner cables with each having: insulated inner conductor,
    wrapped wire shield, outer polyvinyl insulator. It comes in lengths of
    6', 15' and 25'.

    Dennis

    Original Message
    From: Dwain J. Hill [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=f1Pgmm-5j6BbMQhuu_NYN4bcURIvhQrcd25LakCDM-rUHY1omhAOooo2bgV_JIE-qha9y_kofFTwMazdr4Oc]dwainsworld@e...[/url
    Sent: Saturday, January 18, 2003 3:13 PM
    To: basicstamps@yahoogroups.com
    Subject: Re: [noparse][[/noparse]basicstamps] serial cable


    I agree with what the other guys have said, don't run your shield as the
    ground for the stamp.

    Depending on what you have available to you for wire, I suggest you use
    two individual runs of TWISTED shielded twin.

    Do NOT ground the shields at both ends. Ground at computer end only.

    If these don't work, why not consider an FRO link?


    For more information on data cabling, try a google search on CSDB
    (commercial standard data bus). The info that you will find on such a
    search will be aircraft databus standard wiring, which typically is long
    low speed databus runs in electrically noisy environments.

    Regards,


    Dwain
    Original Message
    From: "Ricky Konvicka" <ricky@m...>
    To: <basicstamps@yahoogroups.com>
    Sent: Saturday, January 18, 2003 4:08 AM
    Subject: [noparse][[/noparse]basicstamps] serial cable


    > I have a stamp sending data to a PC in a noisy industrial environment.
    Inside the cable I am using 4 wires, serial in, serial out, ATN and
    ground which is the shield. I also have a jumper on the ATN line so the
    PC will not reset the stamp when it is shut down. I am getting spuratic
    events when plugging and unplugging the cable, like lock ups and resets.
    The ground on the stamp side is not an earth ground, just a dc ground on
    the board which is not earth grounded either. What is the preferred
    method for making this
    connection or cable? It would be an earth ground on the PC side of the
    cable. Would caps or resistors help in any way? Oh the cable is about
    200ft long. I know this seems long but the data gets there flawlessly.
    It never misses a beat. Thanks in advance!
    >
    >
    > [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/
    >
    >
    >
    >



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  • ArchiverArchiver Posts: 46,084
    edited 2004-02-10 23:20
    I need to operate a basic stamp on 2 different locations. I want to
    leave the serial cable in position at eatch site. Therefore, what is
    the cable configuratin so that I can purchase a new one localy.
    Satchid
  • ArchiverArchiver Posts: 46,084
    edited 2004-02-10 23:40
    In a message dated 2/10/2004 6:33:55 PM Eastern Standard Time,
    satchid@p... writes:


    > I need to operate a basic stamp on 2 different locations. I want to
    > leave the serial cable in position at eatch site. Therefore, what is
    > the cable configuratin so that I can purchase a new one localy.
    > Satchid
    >

    Just ask for a standard serial cable. Make sure it is not a null modem
    cable.


    Sid Weaver
    W4EKQ
    Port Richey, FL


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2004-02-11 14:21
    Yes, I do this myself.
    You need a DB-9 Male to DB-9 Female cable,
    with all 9-pins wired STRAIGHT-Through.

    This is sometimes called a Serial Mouse
    Extension Cable, or a Modem Connection
    Cable.

    Do NOT use a 'Null-Modem' cable -- this is
    not wired the way you need for the BS2.

    --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...> wrote:
    > I need to operate a basic stamp on 2 different locations. I want to
    > leave the serial cable in position at eatch site. Therefore, what
    is
    > the cable configuratin so that I can purchase a new one localy.
    > Satchid
  • ArchiverArchiver Posts: 46,084
    edited 2004-02-11 21:24
    Thank you, it works.

    Original Message
    From: Allan Lane [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=HpS_n66Reta1X_tkSFyQI0Z_AFSyaH5oe4C0EJXvpmt7uX6Aidc9yn2vvD2BjEaNzNKWAF7mLiaQD8J_0OVG9TrFGmI]allan.lane@h...[/url
    Sent: woensdag 11 februari 2004 15:22
    To: basicstamps@yahoogroups.com
    Subject: [noparse][[/noparse]basicstamps] Re: serial cable


    Yes, I do this myself.
    You need a DB-9 Male to DB-9 Female cable,
    with all 9-pins wired STRAIGHT-Through.

    This is sometimes called a Serial Mouse
    Extension Cable, or a Modem Connection
    Cable.

    Do NOT use a 'Null-Modem' cable -- this is
    not wired the way you need for the BS2.

    --- In basicstamps@yahoogroups.com, "satchid23" <satchid@p...> wrote:
    > I need to operate a basic stamp on 2 different locations. I want to
    > leave the serial cable in position at eatch site. Therefore, what
    is
    > the cable configuratin so that I can purchase a new one localy.
    > Satchid



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