Version 1.1

This is only a small feature release.

New and changed features

• The digipeating method is now configurable via the APRS Config→Advanced→Digipeating menu item. The following settings are available:
  • off: Digipeating is not requested.
  • Dest. Call: Destination call digipeating. This was used up to version 1.0.
  • WIDEn-n: The “classic” digipeating mode, requested by putting WIDE1-1 in the repeater path.

Please note: due to the internal settings storage method, the digipeating will be off after the upgrade. Make sure you check this new setting if you want your packets to be digipeated.

Version 1.0

A late Christmas present for all of you! 🎄 🎁

This release brings some long-awaited features:

• A new and registered APRS destination call: APLETK. (see issue #12)
• You can configure whether tracker and/or receiver should be enabled automatically after a reset. Use the APRS Config→Advanced→Startup state menu item to configure that. (#19)
• The firmware can be “shut down”, which means that all activity is stopped and the display is cleared. Useful before the battery is removed for a longer time. (#11)
• LoRa RF frequency can be configured. (#18)
• A new BLE based configuration interface has been added to allow access to all internal settings. The Python-based client script has been updated accordingly.

See the changelog and the updated documentation for further details.

Version 0.9.0

This release vastly improves the behaviour of this firmware on-air.

Improvements to the APRS Implementation

Special thanks in this area go to Thomas DL9SAU who provided provided ideas, suggestions and code to improve the APRS protocol implementation in this firmware.

The following changes have been made:

• Handle further common frame types (such as positionless weather reports) as valid frames and show their info field in the RX comment area.
• Keep the last known position of a station if a positionless frame was received from that station.
• Airtime reduction:
  • Use “destination call digipeating”. Instead of the usual "WIDE1-1" in the path, SSID "-1" is set in the destination call field. This still allows digipeating while saving 6 bytes in every APRS transmission.
  • No digipeating is used for weather reports.
  • Do no longer transmit the APRS comment in every frame. The comment is transmitted at least once per hour or in every 10th position packet, whatever happens first. However, the minimum time between two comment transmissions is 10 minutes.
  • Position updates are now forced every 30 minutes (previously 15 minutes) to reduce the airtime impact of non-moving stations.
• Use human readable version of the !DAO! field (format !W42! instead of !wnn!). As this firmware internally calculates in 32-bit floating point, position resolution is limited to 2.38m anyway. The new DAO variant’s resolution is 1.8 m (or better), so no precision is lost by this change.
• Weather data is now compliant to the APRS specification and always includes the required c, s and g fields.
• Send weather data in positionless weather reports. This completely separates weather data from position data and the previous toggling of the symbol between the selected one and the WX symbol is no longer necessary. Positionless weather report are inserted between the regular position updates every 5 minutes, if enabled.
• Improved robustness during frame generation. If a field does not fit into the frame memory, it is dropped completely instead of truncating it. This prevents parser errors at the receiver.

Other Improvements

• The compass displays now show a nice arrow instead of a simple line. This should make the direction easier to see.

Fixed Bugs

• Fixed APRS RX history handling: while the RX list was not full, newly received packets were always appended to the list even if the station was heard before. This caused a single station to fill up the entire list.

Version 0.8.1

This is primarily a bugfix release.

New and changed features

• Decreased the BME280 readout and display refresh interval to 15 seconds.
  • Readout/Refresh only happen if power is already on for these modules, for example while the tracker is running.
  • Auto-refresh happens only once per hour in standby.

Fixed bugs

• Fixed a crash/hang on startup (during settings storage initialization) that could happen when this firmware is first installed.
• Give GNSS module more time after a reset. That ensures that it can be configured properly over UART and fixes the bug that GNSS details were not shown on some devices.

Documentation

There is some work-in-progress documentation now, describing the features of the firmware in more detail than the README.md could. Also, there is a user guide describing how to operate the T-Echo with this firmware.

The documentation is written in AsciiDoc.

Version 0.8

IMPORTANT: If you upgrade from version 0.6 or older, it is be possible that you can no longer write to the BLE characteristics from a device you already paired with the T-Echo before the update. Please follow the troubleshooting section in README.md in this case.

New and changed features

• Quickly toggle RX/TX on or off by holding the touch button and shortly
  pressing the lower-left button. The button combination enables or disables
  receiver and tracker in the following order:
  • both RX and TX off
  • RX on, TX off
  • both RX and TX on
  • TX on, RX off
  • both RX and TX off again

Fixed bugs

• Fixed small inconsistencies in the button handling module.

Thanks

• to Tom DL5NEN for suggesting the quick RX/TX switching method.

Version 0.7

Version 0.7

IMPORTANT: After installing this update, it is be possible that you can no longer write to the BLE characteristics from a device you already paired with the T-Echo before the update. Please follow the troubleshooting section in README.md in this case.

The weather reporting feature is considered unstable. Please test it and report any issues you find. Also, please open an issue if you have suggestions!

New and changed features

• Raise the BLE security level:
  • The device now supports BLE 4.0 passkey pairing: The T-Echo shows a passkey that you have to type at your phone/laptop. A successful passkey pairing ensures man-in-the-middle protection.
  • Passkey pairing is now required to write to any characteristic. Thus (for example) the call sign can only be changed if you can see the T-Echo’s passkey.
• Allow to cold-restart the GNSS module via the menu.
• Added support for the BME280 environment sensor:
  • detect the sensor on firmware startup (may not be available)
  • read temperature, humidity and pressure values every minute (at most)
  • as the sensor is connected to the peripheral power which also supplies the GNSS module, a measurement is only started if peripheral power is already on.
  • measurement is triggered
    • by a timer every 60 seconds
    • by any button press
• Weather reports based on the BME280’s values can be transmitted via APRS:
  • optional, configurable via the advanced APRS configuration menu.
  • Weather reports are transmitted when a transmission is triggered by the tracker, i.e. no additional packets are sent. They include the latest BME280 readings available at that time.
  • In weather reports, the symbol code is forced to /_. This is required by the APRS specification. All other data is included as usual.
• Changes in the menu:
  • New submenu GNSS Utilities in main menu.
    • Renamed the GNSS Warmup to Keep GNSS powered and moved it to the new GNSS Utilities submenu.
    • Added a new menu entry Cold restart to the GNSS Utilities submenu.
  • New entry Weather report in APRS Config → Advanced which allows to enable transmission of weather reports.

Version 0.6

Version 0.6

New and changed features

• Track the current wall clock time (in UTC) and synchronize it to GNSS when enabled.
• Added a clock screen showing the current time and date.
• Added decoder overview screen showing the receiver history, including time since
  the last error.
  • For each decoded station, the time since reception and call sign are always shown.
  • If own location is available, distance and course are also displayed.
• Overview screen is a mini menu where one station can be selected for the details screen.
• Merged decoded packet and raw packet data screens into one “packet details”
  screen. The contents depend on the entry selected in the overview screen:
  • For decoded packets, the details screen corresponds to the previous decoded
    packet screen, with the following changes:
    • Moved distance to the received station below the graphical course representation.
    • Removed numeric course to the station.
    • Show two lines of APRS comment.
    • Show received signal properties (RSSI, SNR, SignalRSSI).
  • For packets that cannot be decoded, a screen similar to the previous raw
    data screen is shown:
    • Show error message, raw packet and signal properties on one screen.
• Improved the tracker status screen:
  • Heading is now shown similar to the course on the packet detail screen.
  • Speed is in km/h and moved below the heading display.
  • DOP was removed (still available from the GNSS screen).
• Pressing the touch button now always refreshes the current screen.

Please note: The binaries are now named differently than in v0.5 and earlier. Use t-echo-lora-aprs-v0.6.uf2 for upgrades and t-echo-lora-aprs-with-sd-v0.6.uf2 when switching from another firmware (for example Meshtastic or SoftRF).

Version 0.5

Version 0.5

New and changed features

• Show own heading as dotted line in the RX direction diagram for comparison
  with the course to the received station.
• Add option to send the battery voltage in the APRS comment field.
• Changes in the menu:
  • Introduced “Advanced” submenu below the “APRS Config” submenu which
    includes the new Battery Voltage option.
  • Moved the Frame Counter option to the new “Advanced” submenu.

Fixed bugs

• Last character of APRS comment was missing in the parsed packet view.
• fixed crash on startup after initial installation. This happened if the flash
  area where the settings are stored was not clean (erased), i.e. contained data
  from a different firmware. In this case, the settings area is now erased and
  the flash storage is re-initialized.

Version 0.4

New and changed features

• Support for sending and decoding more APRS packet formats:
  • Compressed data format as specified in APRS 1.0. Encodes high-precision latitude, longitude, altitude and symbol in only 13 characters!
  • !DAO! extension as specified in APRS 1.2 for enhanced location precision in uncompressed packets.
• The following fields in the APRS info field are now optional:
  • Altitude (always on in compressed packets)
  • !DAO! (always off in compressed packets)
  • Packet counter
  • The default configuration is identical to v0.3: Altitude = on, !DAO! = off, Packet Counter = on.
• Reorganized the menu:
  • new “APRS Config” submenu in main menu that allows to configure the options listed above.
  • moved the symbol selection menu to the new “APRS Config” menu.
• Tuned the tracker transmission conditions:
  • Trigger transmission at 30° heading change (previously 45°).
  • Force transmission 15 minutes after the last one (previously 3 minutes).

Fixed bugs

• correctly display negative SNRs for received packets (these were previously shown as +32 to +65 dB SNR).

Version 0.3

• Decode and count visible and tracked GNSS satellites
• Reorganized the status bar at the top of the screen
  • Removed precise battery voltage
  • Battery graph improved
  • Show GNSS status
    • dashed border = GNSS disabled
    • solid border, white background = GNSS active, but no valid position available
    • solid border, black background = Position valid
• Increased fast advertising timeout to three minutes again
  • Allows faster reconnects after the BLE connection was lost
• Fixed an issue where the incorrect symbol code was provided via BLE
• Added a simple BLE client for the PC written in Python