Firmware for M5Stack Cardputer ADV that shows GNSS data (grid + satellite sky plot + battery) and sends the current position as an APRS (TNC2) position packet over LoRa (EU868).
- Reads GNSS (GPS) and displays:
- Lat / Lon / Alt / Speed / Date / Time
- Fix (2D/3D), sats seen/used, fix age
- Satellite “sky plot”
- Battery %
- Builds an APRS TNC2 position string and transmits it with LoRa EU868
- LoRa transmit is non-blocking (runs in a FreeRTOS task), so UI/GNSS keep updating
- ENTER: transmit once
- L: toggle auto transmit every 5 minutes
- C: open config menu
- S: screen on/off
- Type to edit current field
- DEL = backspace
- ENTER = next field (last field saves and exits)
Note: in config mode, L/S/C are treated like normal text (they do not trigger actions).
The first boot opens the config menu automatically. You can open it later with C.
Fields:
- Callsign (can be empty, but TX will be blocked until set)
- Destcall
- Path
- Symbol table + symbol code
- Comment (optional)
This is the exact workflow used for this project: flash once, then export BIN from the device using M5Burner, and finally load that BIN whenever you want.
- Flash the firmware to the Cardputer ADV once (for example from Arduino IDE).
- Open M5Burner
- Connect the Cardputer ADV via USB
- Go to USER CUSTOM
- Open Firmware Exporter
- Select the correct serial port and click Export
- Save the exported file (example:
CardputerADVAPRS.bin)
Now you have a BIN you can reuse.
- Open M5Burner
- Go to USER CUSTOM
- Choose Burn (or “Burn local firmware” depending on your version)
- Select your exported
CardputerADVAPRS.bin - Select the correct serial port
- Click Burn
That’s it.
- This transmits APRS-like packets over LoRa RF. Make sure you are compliant with your local rules for EU868 and amateur radio.
- If you want the position to appear on APRS-IS/aprs.fi you normally need an IGate receiving your RF and injecting to APRS-IS (this firmware does not talk to APRS-IS directly).