I am making a custom connector that will carry several signals to a test board including RS-422 RX+/RX- and TX+/TX-. The strange thing is that I didn't find a standard pinout for the DB9 connector used for the RS-422!
So I checked the manufacturer of the RS-422 PCI card in my PC and found their own pinout which means that my test board can only be interfaced to this RS-422 from this manufacturer and won't work on solutions from others?! Is that normal for this "standard" protocol?!
Best Answer
From Wikipedia:
So, according to the Wiki, there indeed is no standard for the pin assignments of RS-422 on a DB-9 connector.
In addition to that, different websites say different things:
So there probably indeed is no standard.