Sunday, March 10, 2013

aprx on the TNCPi

Once the TNCPi has been assembled, attached to the Raspberry Pi and tested, getting aprx running on it is fairly straightforward.

1) Install the subversion client:

sudo apt-get install subversion

Fetch the aprx sources:

svn co src
cd src/trunk
./configure && make clean all
sudo make install

2) Configure aprx

Refer to the aprx documentation for full details and sample configurations, available at aprx's home page and keep the following in mind:

  • The name of the serial device is /dev/ttyAMA0
  • Baud rate is fixed at 19200

Note: this is the data rate for the serial interface between the Raspberry Pi and the TNCPi, the RF data rate is fixed at 1200 baud.

The file to edit is /etc/aprx.conf

3) Run it!

To test the configuration, you can run aprx as follows:

aprx -i -vvv -ddd

The switches are:
  -i makes it interactive rather than background
  -vvv makes the status messages very verbose
  -ddd makes the debug messages very verbose

You can stop aprx with ctrl-C to make changes to the file, then start it again with the same command.

There are sample startup scripts in aprx's documentation that you can use to build one to suit your needs.

Once you have the configuration right, you can start it in the background simply by typing:



  1. Did you use the TNC-X via serial port or via I2C ? In other words, does the I2C configuration create tty devices for aprx to use ?

    1. I'm using the TNCPi via serial port, not I2C.