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APRS

APRS frames are AX.25 UI frames with PID 0xF0. AXLoRaTNC decodes incoming APRS frames and logs the parsed content (position, message, status, weather) to the console.

Position beacon

text
beacon aprs 52.0167 4.7000 /> LoRa TNC on 869.480 MHz

Arguments: lat lon [symbol-table+code] [comment]. Default symbol is /> (car). This sets the destination to APRS and formats an uncompressed APRS position info field automatically.

Then enable the beacon:

text
beacon interval 600    # every 10 minutes
beacon on

Beacon commands

text
beacon                         # show config
beacon on / off
beacon now                     # transmit immediately
beacon text <text>             # set info field manually
beacon dest <CALLSIGN-SSID>    # set destination (default CQ)
beacon interval <seconds>      # 10–86400 s
beacon path <CALL1,CALL2|off>  # set repeater path

Digipeater

text
digi on / off
digi mode ui        # relay only UI frames (default, for APRS/beacons)
digi mode all       # relay UI and connected-mode AX.25 frames
digialias WIDE1-1   # set secondary alias
digialias off

The digipeater matches the first unrepeated address against the node callsign or configured alias, sets the H-bit, recalculates FCS, and retransmits. A 30-second duplicate cache suppresses UI-frame loops.

Mheard

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mheard          # list stations heard: uptime timestamp, RSSI, SNR, frame count, via flag
mheard clear    # reset the table

The table stores up to 20 entries with first-heard and last-heard times, RSSI, SNR, frame count, and whether the station was heard via a digipeater.

Released under the MIT License.