PC Interface. Why the second RJ45 Serial ?

Discussion in 'C-Bus Wired Hardware' started by Charlie Crackle, Sep 2, 2006.

  1. Charlie Crackle

    Charlie Crackle

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    I have always wondered why there are 2 RJ45 Serial Ports.

    I can understand 1 port. Whey would you have something in both RJ45 serial ports ??


    Charles
     
    Charlie Crackle, Sep 2, 2006
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  2. Charlie Crackle

    ashleigh Moderator

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    G'Day Charlie

    'Twas done before my time, so I have NO IDEA WHY.

    Seems to me to be one of those very odd decisions that was made back in the mists of time for which there is now no rational explanation.

    Chalk it up as one of those eternal mysteries :confused:
     
    ashleigh, Sep 3, 2006
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  3. Charlie Crackle

    Richo

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    my personal theory is that it was because we have a double RJ45 connector part as part of normal stock, but at least back then we probably didn;t have a single. May have been cheaper to use the double part than create a new stock item for just the sigle connector...... but this is just my theory.
     
    Richo, Sep 3, 2006
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  4. Charlie Crackle

    Newman

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    My best guess as to why there's 2 RJ45's is so that the same enclosure half could be used for each side of the unit rather than have 2 sets of tools for 2 different enclosure halves. We don't have a double RJ connector, it's 2 singles side-by-side.
     
    Newman, Sep 4, 2006
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  5. Charlie Crackle

    Jesmond

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    Guys,

    Just out of curiosity can you use the CTouch Serial to RJ45 connector to connect to the PCI instead of the normal DB9 top DB9 Cable ?

    Also can I use the 2 x RJ45 Serials ports on the PCI to connect to 2 devices (ie my alarm and my serial connected touchscreen)

    Regards
     
    Jesmond, Sep 4, 2006
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  6. Charlie Crackle

    NickD Moderator

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    Yes

    No.. RS-232 doesn't work like that. You would have the two TX pins on your devices trying to drive each other to different levels (amongst other things).

    Nick
     
    NickD, Sep 4, 2006
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  7. Charlie Crackle

    wanricky

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    It won't work if you connect two RS232 connection to a PCI, even if one is DB9 and one is RJ45 side. They all link together, I think.

    My guess on the two RJ45 slots was that it allows potential two com ports (one In, one OUT..etc) when the design changes. Probably the slow transfer rate has limited all that. When there is PAC now, I guess there will be not big changes for the PCI.
     
    wanricky, Sep 4, 2006
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