How do I change from full-duplex to half-duplex using Linux?


FDX to HDX GtkTerm Linux.pdf (67.6 kB)

files/pages/support/faqs/Images/RS-422 485 9pin pinout.png

You will need to either short pins 1+6 and 2+7 or construct a Half-Duplex cable with those pins shorted.

GtkTerm works in a very similar way to most terminal applications.
To install GtkTerm, please follow these steps:

  1. Open Terminal
  2. Type:  sudo apt-get install GtkTerm
  3. Once installed, go to Terminal and type: GtkTerm

Once GtkTerm has been installed, follow these steps to change from Full-Duplex to Half-Duplex:

  1. Open the GtkTerm application by typing in the Terminal: GtkTerm
  2. Go to the configure tab
  3. Enter the port information: Port, speed (Baud), parity, bits, stop bits and flow control – Press OK when done
  4. Now go to Control Signals
  5. Press Toggle DTR (F7)

At the bottom of the GtkTerm application, there are letters saying: DTR RTS CTS CD DSR I

When DTR is greyed out, it means it has been toggled properly using the Control Signals option. This is now in half duplex mode.