How do i set up my cat 5 port to act like a serial port?

Posted on 2005-04-13
Last Modified: 2010-04-10
We're doing a project where we need serial to serial communiction.  Unfortunately, my DELL laptop did not come with a serial, only usb and cat 5.
I have an alom converter/connection which allows a cat 5 to be plugged in on one side, and its a serial on the other side. The communication over the cable then becomes serial.
BUT, the cat 5 is always plugged into the "A Lom" port (a cat 5 that has serial protocol).
Is there any way to configure my cat 5 port to act like the A Lom port and make it think that its a serial connection?
Any help would be greatly appreciated!

I'm using Windows XP.
Question by:chinese_bunny
    LVL 32

    Assisted Solution

    Get a usb to serial converter, that way you can use your USB port for serial access.

    Check it out:


    Author Comment

    we already had a usb-serial connector and it broke on us.  Another one is like $30. We cannot order it online, because we need it
    But i already have alom and cat 5, so that would be saving us 30$
    LVL 27

    Expert Comment

    I think you're out of luck.  I'm not sure what "A Lom" is - I haven't heard of that.  Cat5 is a type of cabling, not a connection technology.  Serial protocols can run over Cat5.

    If you're in the US, near a major city, then try to find a store with a converter.
    LVL 27

    Expert Comment

    Ps.  USB is serial ... Universal SERIAL bus.  

    Author Comment

    let me clarify:
    we do not HAVE a usb to RS232 connector. We had one...and it broke.  We do not want to spend $30 on another one when i already have the matierals for cat5 - rs232.
    Cat 5 = ethernet.  Cat 5 just means that is uses ASTERIX Catergory 5 protocol.  Ie. Theres cat 10, cat 11...etc.
    Rs232 (serial..i use these interchangeably) - the 9 pin connection.

    @pseudocyber --- i dont know what you mean by "connection technology".  It is a cable, and it DOEs use a certain protocol, so it IS connection technology?? @_@  A lom's are cat 5 (ethernet) ports that allow a RS232 connection.  So if one end is plugged into the A lom, and the other end is plugged into serial, you can Tip into the machine.  It basically thinks that there's a RS232 connection between the two.  A loms come standard on the backs of alot of suns, such as the V120, V210, etc. since no serial (rs232) is provided.

    I am not sure what kind of configuration is done on an ALOM port, whether its hardware or software.
    I just wonder if there is way i can "trick" my ethernet port to thinking its an alom port.

    note: I am aware that i could go buy a usb-serial connector...i was just wondering if the above asked question was feasible.
    LVL 27

    Accepted Solution

    >>I just wonder if there is way i can "trick" my ethernet port to thinking its an alom port.

    No, I'm pretty sure you can't.

    >>It is a cable, and it DOEs use a certain protocol, so it IS connection technology??

    Protocols and cabling are usually fairly independent.  Cat5 cable can run serial, ethernet, token ring, apple talk, etc.  Obviously it can't run FDDI or 802.11 - which are dependent on the type of media (fiber or wireless) ... but this is getting off topic.

    I think your answer is you're out of luck unless you buy another USB to DB9/25 converter.

    Author Comment

    a alom port takes in a cat 5 cable, so unless its hardware or firmware designed, i feel as though through programming, there may be a way to have it read in a certain.
    i'll keep looking.

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