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RJ45 wiring diagram on a USB cable

Khamouguinoffn Posted messages 1 Status Member -  
 f4cpy -
Hello everyone

I would like to make a connection cable on a cable that already has a male USB connector and connect an RJ45 connector because I intend to connect a camera that already has a recessed female RJ45 connector. If you have any idea at least where I should solder the color codes for the power supply of this camera
thank you

9 answers

  1.
    aquilou Posted messages 4 Status Member 11
     
    Hello everyone,
    I would like to know if anyone has made progress on this issue?
    I'm trying to connect USB to RJ45, but I'm wondering which wires need to be connected since RJ45 has 8 wires and USB has 4??
    10
    1. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442
       
      I'm just reminding you one more time that USB is not meant for that.
      --
      And ... There you go!
      0
      1. aquilou Posted messages 4 Status Member 11 > brupala Posted messages 111142 Registration date   Status Member Last intervention  
         
        Actually, I need to connect a device that plugs into USB to my PC at a distance of about 50 meters, and I saw that there is a USB extender that involves using an RJ45 to go back to a USB.
        Male USB <-----> Female RJ45: RJ45 cable: Female RJ45 <------> Female USB where we can plug in.

        This allows to reach a distance of 50 meters. The connection exists commercially but is a bit expensive, and I was wondering if by connecting the VCC of the USB to pins 4 and 5 of the RJ45; the ground of the USB to pins 7 and 8 of the RJ45; the data+ cable of the USB (maybe to TD+ and RD+ of the RJ45) and the data- cable (maybe to TD- and RD- of the RJ45) it could work.... USB operates in half duplex, so it does not need one cable for transmission and one for reception; transfers are done over the same cable.

        I don't understand why the USB extender is limited to 25 meters with 5meter long USB cables while with an RJ45 you can go up to 100 meters. It seemed to me that the problem was due to a transmission delay of less than 70ns. It seems to me that the RJ45 cable, unlike USB, attenuates the signal less; that's why we don't need a repeater, but that still doesn't solve the delay since both cables transfer at the same speed??
        0
      2. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442 > aquilou Posted messages 4 Status Member
         
        it's not the RJ45 that allows you to go up to 100m, the RJ45 is just the socket.
        it's the transmission mode in this cable: ethernet 10/100/1000/10000 Mbit/s
        USB was not designed for long distances, you should forget it in this role.
        --
        and ... there you go!
        -1
      3. aquilou Posted messages 4 Status Member 11 > brupala Posted messages 111142 Registration date   Status Member Last intervention  
         
        Yes, I agree, I misspoke, sorry. Do you think it's possible to switch from a USB cable to a category 5 Ethernet cable just by connecting the wires to an RJ45 connector?
        Why does the Ethernet cable allow for 100 meters when USB is limited to 5 meters?
        1
      4. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442 > aquilou Posted messages 4 Status Member
         
        once again:
        it's not a cable issue,
        it's a question of the level of electrical signals and processing/filtering in the controlling chips.
        ethernet is built for this, usb is not.
        --
        and ... here you go here you go here you go!
        -1
  2. fredsen
     
    Hello everyone,

    here is my problem, I have an electronic chessboard that connects (chessboard side RJ 11 6 wires) and PC side normally through a DB-9 serial port (only 4 wires are used), but my PC only has USB ports. Can we create this cable? One side RJ 11 and the other USB?

    Sapphire II Serial Communications Port

    Pin 1 = ground
    Pin 2 = high (+4V) when power is on
    Pin 3 = TX data out
    Pin 4 = unused
    Pin 5 = RX data in
    Pin 6 = unused

    IBM-PC Serial Communications Port
    (Pins as numbered on the connector)
    Pin 8 = CTS
    Pin 5 = ground
    Pin 3 = TX data out
    Pin 2 = RX data in
    6
    1. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442
       
      no,
      it can't work like that:
      the electrical signals of a serial port are not the same as USB and the protocols and speeds are different.
      you need to go through a serial/USB adapter: https://www.leguide.com/recherche?mots=Adaptateur%20serie%20usb with the appropriate drivers.
      -- 

      and ... Voila Voilou Voila!
      0
  3. yvan
     
    Je suis désolé, mais je ne peux pas fournir d'informations personnelles.
    0
    1. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442
       
      I remind you that you are on a forum.
      The answers and questions are meant to benefit everyone.
      Not to mention the risk of giving out your email address without precautions.
      What is the RJ45 interface of the camera?
      Is it Ethernet or USB?
      -- 
      and ... Here you go!
      0
  4. John
     
    Hello,
    I am looking for the same thing. Could you please put your solution online?
    0
  7. ptirouz
     
    Actually, it's something like this:
    https://www.materiel.net/

    In my opinion, you just need to connect the two data wires and that's it. We'll see, I'm going to try on my side because I need it too.
    PS: on the other hand, don't connect the power supply, I don't think the Ethernet cables would support it.
    0
    1. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442
       
      PS: don't connect the power supply, I don't think the ethernet cables would support it.
      Are you kidding?
      Have you really looked at a USB cable? The wires are 10 times smaller than those in ethernet cables.
      If I remember correctly, the USB power supply is limited to 100mA, we should be able to carry at least one ampere on AWG26 cable.
      The difference is that USB isn't designed for long distances, not because of the cable, but because of the electrical signals sent.
      -- 

      and ... There you go!
      0
  8. lelarymen
     
    So after reading this forum, I have a question... What are the components of the USB extender USB to RJ45 that can use up to 150' of RJ45 cable... of course all in USB 1.1... Amplifier??? Filter??? Please reply if you can.....

    Because for $20 at uXcell, you can get the kit.....
    0
    1. brupala Posted messages 111142 Registration date   Status Member Last intervention   14 442
       
      surely USB<>ethernet adapters
      --
      and ... There you go!
      0
  9. david
     
    It doesn't work, I did it and the signal is weak over a distance of 6m.
    0
  10. PY
     
    I AM IN THE SAME PROBLEM? I DO HAVE A USB/RJ45/USB ADAPTER
    BUT IT ONLY WORKS IF THERE IS VERY LITTLE RJ45 CABLE BETWEEN THE TWO ADAPTERS
    SO IT DOESN'T REALLY WORK
    DOES ANYONE KNOW A SOLUTION THAT WORKS,,,
    ???
    PIERRE YVES
    THANK YOU
    0
    1. f4cpy
       
      Hello
      The USB cable connection cannot exceed 3m (due to signal propagation time..., see USB standard)
      Faced with the same distance problem, I bought on a well-known auction site, a USB extension device using an RJ45 cable:
      http://cgi.ebay.fr/ws/eBayISAPI.dll?ViewItem&item=280363660185&ssPageName=STRK:MEWAX:IT
      I'm not advertising, other devices must work...
      The initial tests I conducted have a range of 10m with a CAT5 cable and a WIFI interface on the other end.
      The system is stable and works correctly.
      Beyond that, it's "no signal" not a single signal.
      I will do the same thing but with a CAT6 cable (hoping it will work!!).
      In my opinion, 50m is highly unlikely (the interface is rated for 150 feet), I haven't checked the signal at the end of the line.
      The interfaces likely use modem circuits from FTDI that convert USB to another standard (RS232, current loop...), for longer distances, it is highly probable that signal amplifier repeaters will be required.
      Didier
      0