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Do I need to terminate modem control signals if I’m not using them?

It is always a good idea to terminate any unused signal lines. Floating signals can generate interrupts and drastically degrade system performance. The Sealevel SeaCOM serial driver provides a means of suppressing modem control interrupts. The driver features can be located in the Microsoft Windows Device Manager. If you are not using the Sealevel SeaCOM serial driver, or are using a different operating system, terminate each modem control line by connecting it to its complement:

  • Connect CTS to RTS
  • Connect DCD to DTR to DSR