Configuring Serial TNC Ports

Terminal-Node Controllers (TNC) or radios containing built-in TNCs are connected through a computer serial port using the KISS protocol.

To add a new TNC port, click the Add button on the Configure Ports tab. The port editing dialog will appear. Set the port type to Serial_TNC.

screenshot of serial TNC configure panel

The other parameters you will need to specify for the TNC are:

Note that this port type supports receiving from multiple KISS data ports over the same serial device, although it only transmits over data port #0. This supports the Byonics TinyTrak 4's GKRELAY command, which allows a GPS receiver connected to the TinyTrak (rather than to the computer running YAAC) to forward GPS sentences over the same cable used to send and receive APRS/AX.25 packets.

The "Test Port" button provides a means of verifying that you have connected to the correct place; it opens a terminal window connected to the configured serial port so that you can manually test the TNC for the desired operation. To complete testing, close the terminal window.

Once you have the settings the way you want them, click OK. Ensure that the TNC is connected to the port before you click OK. At that time, the port will issue commands to the TNC to put it in KISS mode, and then wait for AX.25 packets to arrive.

If you want to create a Serial_TNC port on a new installation of YAAC using the -createport option, the port_description is of the format:


where comportname is the name of the serial port on your operating system, such as COM3 or /dev/ttyUSB0, and baudRate is the serial port speed; this must be specified even for USB devices that don't have a configurable baud rate. transmitEnabled is either "true" or "false" (without the quotes) depending on whether you want this port able to transmit packets. Any digipeatAlias specified here must also already be specified on the expert-mode configuration dialog's Digipeat tab. If the TNC is not KISS-only, a kiss-command expression (as described above) should be specified after the semicolon.