aprs-mqtt-bridge/python-ax25/README.md

python-ax25

Python AX.25 Module for Python3

Introduction

This is a python module designed for Python3 to access AX.25 features. This module is a C extension that can access the AX.25 interface from the Linux kernel.

This C extension is inspired from pyax25 https://github.com/ha5di/pyax25

Installing the Module

Clone the Git repository

$ git clone https://github.com/josefmtd/python-ax25

Install the module by running the install script inside the python-ax25 directory

$ cd python-ax25
# ./install.sh

Module Functions

Before using any of the functions, make sure to load all the available ports using config_load_ports()

pythonax25.config_load_ports()

Returns = number of available ports (int)

To get the names of available ports, use the config_get_first_port and config_get_next_port

pythonax25.config_get_first_port()

Returns = name of first port (unicode string)


pythonax25.config_get_next_port(portname)

Returns = name of port after 'portname' (unicode string)

To retrieve further information for each available port, use these functions:

1. config_get_port_name(device)
2. config_get_address(portname)
3. config_get_device(portname)
4. config_get_window(portname)
5. config_get_packet_length(portname)
6. config_get_baudrate(portname)
7. config_get_description(portname)

To change the callsign from ASCII to network format and vice versa, use the functions ascii_to_network(callsignascii) and network_to_ascii(callsignnetwork)

pythonax25.ascii_to_network(callsignascii)

Returns = callsign in network format (byte literal string)


pythonax25.network_to_ascii(callsignnetwork)

Returns = callsign in ascii format (unicode string)

For receiving AX.25 packets, the packet socket is mostly used in C programs. Start a socket by using packet_socket() and begin receiving by using packet_rx(fd, timeout)

pythonax25.packet_socket()

Returns = file descriptor (int)


pythonax25.packet_rx(fd, timeout)

Returns = Protocol and Address (tuple of int and string) and packet (byte-literal string)

For sending APRS messages, the datagram socket is used. Socket is started by using datagram_socket(), bound to a port by using datagram_bind(fd, srccall, portcall) and send packets via datagram_tx(fd, destcall, message) or datagram_tx(fd, destcall, digicall, message)

pythonax25.datagram_socket()

Returns = file descriptor (int)


pythonax25.datagram_bind(fd, srccall, destcall)

Returns = result of bind (int)


pythonax25.datagram_tx(fd, destcall, message)

Returns = result of transmission (int)


pythonax25.datagram_tx_digi(fd, destcall, digicall, message)

Returns = result of transmission (int)

Closing socket is done by using close_socket(fd)

pythonax25.close_socket(fd)

Returns = result of close (int)

2020 - Josef Matondang