Blandingen af datavært-typer (kommunikationsudstyr/DCE, terminaludstyr/DTE), individuelle datavært styresignaleringskrav, forskellige RS-232 kabler ("standard" og null-modem="krydset kabel"), manuelle og/eller automatiske konfigureringer gør at etablering af RS-232 dataforbindelser kan være meget besværligt.<ref>Eksempel hvor besværlig det kan være: [https://web.archive.org/web/20170625223918/http://www.windmill.co.uk/rs232-communication.html Understanding RS232 Serial Port Communication] Citat: "...If RS232 is a standard why can't I just use a standard lead to connect together two RS232 ports and expect them to talk to one another? That's a good question...You've plugged your instrument into your computer's COM port, installed your data acquisition software, but no data appears. You suspect it is a problem with your RS232 communications. What do you do?...Obtain all the information available about your instrument or device. You will need to know the number of the com port into which you have plugged your device, the device baud rate, number of bits in the data byte and parity. Enter this information in ComDebug. If you have information about the Stop Bits then use it, otherwise set them to 2. This will at worse slow the message down slightly. See Making Measurements through the COM Port for a detailed explanation of each of these settings..."</ref><ref>Youtube: [https://www.youtube.com/watch?v=1vohtCJeEjU How to troubleshoot serial RS232 communications] {{Webarchive|url=https://web.archive.org/web/20180524023139/https://www.youtube.com/watch?v=1vohtCJeEjU |date=24. maj 2018 }}</ref> Det ultimative RS-232 værktøj at anskaffe, er en RS-232 ''break out box'' til at teste sig frem til en kabelforbindelse som fungerer, når alle andre forsøg på at få en (stabil) forbindelse fejler. (se illustration)
Kommunikation Teknologi