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I have a DB9 to Serial Connection and I am wondering if there is a name or a standard for this configuration. So that i do not have have to make it every-time.

I made a diagram, (stock image: disregard the arrows) and included a picture of the wire.enter image description here

PC3000
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    What is the second connector (the one which is not a DB9)? Is it a Modular 8P8C? – Jack B Jan 27 '20 at 13:31
  • Over many years, too many users have corrupted this kind of serial interface, hence USB. Your desire for a one-size-fits-all connection may cause frustration. It may help to connect via debugging serial software similar to **Realterm**. Or have an oscilloscope handy, or a breakout dongle with indicator LEDs. – glen_geek Jan 27 '20 at 14:21
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    note: the cable clamp should be on the cable jacket, not on the wires – jsotola Jan 27 '20 at 15:13
  • Jack B its a RJ45. Jsotola thank you, that how it came. Thanks for answering – PC3000 Jan 29 '20 at 10:27

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There are a lot of variations of serial communicator protocols detailing the hardware (cables and connectors), bit rates, and what the data package itself looks like (start & stop bits, acknowledge, etc.), but suffice to say, most any modern usage of a DB-9 cable will be for a variant of the RS-232 protocol, which is ironic given that the RS-232 standard calls for a DB-25 D-Sub connector. RS-232 is one form of a specific type of serial communication known as Universal Asynchronous Receiver-Transmitter (UART). See this question for more information about the difference.

In electronic communication in microcontrollers and the like, it's common to only use the Rx, Tx, and GND lines for basic communications at lower voltage levels, but there are numerous other hand shaking signals available.

All that said, I think you are mixing up the pin numbers - you are looking at the pins from the backside of the connector rather than from the front side. I've remapped your pins with this in mind and keeping your original signal colors.

DB-9 Serial Interface- Female Front

So this appears to be the standard 3-Wire RS-232 with a jumper from the Data Terminal and Data Set Ready Signals. These are used to signal that the terminal (DTE) and circuit-terminated equipment (DCE) are ready for transmission. Basically, whatever device that connector is attached to will automatically see a ready signal from the other end whenever it says it is ready, but this might not be used at all, depending on what your cable is actually connecting.

The female connector is traditionally used in the stationary end (like a computer) with the male end used in cables to plug into the female end. But, as mentioned in previous comments, people use these terminations in whatever way is convenient at the time so it can get confusing.

Kurt E. Clothier
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  • Kurt completely get it now. It is actually used for a coin machine transmission from POS to unit, so your comment makes sense.Thanks for taking the time for the Diagram, i know it doesn't look RJ45 (lol). Would you be able to send me the diagram via email? – PC3000 Jan 29 '20 at 10:28
  • @PC3000 For maintenance and troubleshooting purposes, it's not uncommon to find RJ45 or even 3.5mm audio jack terminations for serial cables to keep the footprint small (don't want a big DB-9 or -25 port sitting there). Those terminations are usually only standard within a company or series of parts. You can always right click on the image I made and "save as" to get a copy of it. – Kurt E. Clothier Jan 29 '20 at 13:34