I am having a problem creating a cable to connect with two devices. The first devisce is an Intellivue MP70 that I want to connect to the RS232 port using an RJ45 end. On the other side there should also be a RJ45 connection that should be connected to a Lantronix EDS-MD Server, and i can't figure out the pin assignment.

I got the following image:

enter image description here

And the following table:

enter image description here

However, as you can see this is a connection from RJ45 to DB9. How do I translate this so i get RJ45 on both ends of the cable?

I can also mention that I have access to a RJ45 to Screw terminal adaptor on one side.

  • 5
    \$\begingroup\$ You'll really need to mention what's on the other side of the cable, it seems you know the Intellivue side of things but there are a lot of different schemes for RS232 to RJ45. \$\endgroup\$
    – PeterJ
    Nov 19, 2014 at 11:23

1 Answer 1


You can remap the DB9 to the RJ45 of your Lantronix EDS-MD. i have found a adapter 'pin out' in the user manual.
there are Adapters and Serial Port Pinouts listet - in the overview there is one cable described as

500-153- RJ45-to DB9F
Connects the RJ45 RS232 serial port s of EDS-MD to a DB9M DTE interface of a PC or serial device to check that serial ports in the EDS- MD are functioning properly.

but this one has no drawing.. so i looked at the rest and searched for the 'DB9M DTE'

200.2070A Adapter RJ45-to- DB9F
Allows a standard straight-pinned CA T5 cable to connect the EDS-MD to the DB9M DTE interface of a PC or serial device.

for this is a drawing on page 96: http://www.lantronix.com/pdf/EDS-MD_UG.pdf#page=96&zoom=auto,-169,21
the only problem is there is no direct naming of the signals. but i think you can use the DB9 Pinout to match your mentioned DB9.
So your table would be as following:

DB9 List from Wikipedia

DTE – data terminal equipment
DCE – data circuit-terminating equipment

Name is seen from DTE site.

DTE                     ---------------------->  DCE
RJ45 Lantronix EDS-MD   -   DB9  Name     -    RJ45 Intellivue
                        -   -    PG       -                  
      6                 -   3    TxD      -      7           
      3                 -   2    RxD      -      5           
      8                 -   7    RTS      -                  
      1                 -   8    CTS      -                  
      2                 -   6    DSR      -                  
      4&5               -   5    GND      -      4           
      2                 -   1    DCD      -                  
      7                 -   4    DTR      -                  
                        -   9    RI       -                  

pleas check again - eventually you have to exchange TxD & RxD on one site...


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