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AL205R Firmware

Software applications, data logger operating systems, firmware, and drivers for Campbell Scientific products

AL205R Firmware

v1.5.8

Current firmware for the AL205R.

Revision History

v1.5.8October 21, 2025
  • Changes to support radio connections on hardware with serial numbers beginning with 12-
  • Fix an issue that could cause the IP forward module to restart in the case of repeated DNS failure.
  • Allow query of EMIDs and better report causes of encryption failure.
  • Allow setting RF tail time to 1ms.
v1.5.7October 20, 2025
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  • Fix a rare issue with 1.5.6 that could cause outgoing messages to be dropped under very heavy load.
v1.5.6October 19, 2025
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  • Fix a bug that would cause the A2X to experience extra load on the day before a potential leap second insertion, potentially resulting in dropped messages on June 30th and December 31st
  • Fix a bug that could result in dropped outgoing messages (< 1 in 1000)
  • Improve robustness of internal message routing to make failure less likely in high load situations
  • Fix a bug where the CSV headers for the sensor SET and GET types were not displayed correctly
  • Fix an issue with A2Control's file browser interface where it would not be enabled on connection
  • Fix a bug where A2Control communication would fail after writing configuration to the A2X
v1.5.5March 21, 2025
  • Add a file browser and firmware update interface to A2X accessible through A2Control.
  • Fix a bug with how MANT PDU decryption failures were handled.
  • Log and report forwarded MANT PDUs: forwarded MANT PDUs are now reported on the serial interfaces, sent to the IP forwards, and are recorded in the log files.
  • Added a transmission log to the SD card - transmissions are now logged alongside decoded messages.
  • Firmware updates uploaded via SFTP will always be applied, regardless of if they are an upgrade or a downgrade.
  • Add the ability to send application layer SET messages from A2Control.
v1.5.4March 20, 2025
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  • A2Control update: allow specification of a port in the A2Control network string (e.g., '192.168.32.100:5590' or 'a2x.example.com:9999').
  • Update default leap seconds for 2024.
  • Internal bug fixes.
v1.5.3March 19, 2025
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  • Update sensor IDs in CSV decoding to match spec for MSR5.
  • Improve the handling of audio from some radios to address a case where some messages (< 0.1%) would fail to decode.
  • Begin signing A2Control binaries.
v1.5.2March 18, 2025
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  • Add sensor CSV output lines for locally generated MANT PDUs.
  • Fix a crash that could occur in the decdoer when with messages using 4-byte TBR accumulators.
  • Improve networking behavior: fix an issue where the A2X would not immediately identify a network change and would not request a new IP address; improving handling of changes to and from DHCP in A2Control so that a device reboot is not required for settings to take effect.
v1.5.1March 17, 2025
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  • Fix an issue where the "Total Symbol Errors Corrected" field would have incorrect data in the API2.0 CSV and Binary output.
v1.5.0March 16, 2025
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  • Major release with the implementation of API 2.0. See detailed release nots for more infomration.
v1.4.7March 15, 2025
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  • Fix an issue where USB was sometimes not detected in low power mode.
  • Fix an issue where the watchdog would trigger during the firmware update process.
v1.4.6March 14, 2025
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  • Add a hardware watchdog that will reboot the A2X in the event of a firmware crash or freeze.
  • Fix an issue where leap seconds might not have been properly updated after a new leap second is inserted.
v1.4.5March 13, 2025
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  • Add support for performing ALERT concentration with enhanced IFLOWS data.
  • Fix an issue in A2Control where the software did not correctly decode 3-byte signed integers.
v1.4.4September 30, 2022
  • Fix an issue that would cause data file compression to fail and the device to report a STATUS_IO warning in some cases.
v1.4.2August 16, 2022
  • Decrease settle time after getting initial GPS clock fix.
  • Update sensor IDs of type-5 MSR is A2Control.
  • Add support for time series message in A2Control.
v1.4.1April 12, 2021
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  • Fix a bug that could could updates or other large filesystem writes to file
  • Improve logging of firmware updates to USB drive (will take effect on upgrades after 1.4.1 is installed)
v1.4.0January 8, 2021
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  • Add support for 300 baud serial connections
  • Improve support for Legacy ALERT Concentration: messages are now reported via the serial and IP output streams when they are received, and are then aggregated for later transmission.
v1.3.2June 8, 2020
  • Fixed a bug with "Low Power Mode" on older AL205B/R devices.
v1.3.1May 26, 2020
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  • Update default leap second data.
v1.3.0May 25, 2020
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  • Completed "Low Power Mode" functionality. In low power mode: ethernet is shut off, USB is shut off when not in use, front-panel LEDs are set to blink once every six seconds, and the CPU is set to a lower frequency.
  • Added the API TLV and A2Control functionality to request and reset the number of leap seconds reported by the GPS module.
  • Added the ability to query the current serial port number.
v1.2.8May 24, 2020
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  • Minor A2Control display change.
v1.2.7May 23, 2020
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  • Fixed for TBR's with floating point accumulator.
  • Allow setting 250ms TDMA slot and 12ms tx delay.
v1.2.6May 22, 2020
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  • Additional fixes for an issue that would prevent com ports from being listed in the drop down.
v1.2.5May 21, 2020
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  • Windows fixes for A2Control.
v1.2.3May 20, 2020
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  • Fixed an issue with A2Control where a config file could not be loaded if one had already been loaded.
  • Add support for setting a destination address in A2Control's "Send GSR" window.
  • Add Bluetooth support.
v1.2.2May 19, 2020
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  • Fixed an issue with A2Control where TBR data would not be displayed if there were no time offsets.
v1.2.1May 18, 2020
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  • Fixed an issue where address list data was not properly refreshed after a configuration change without rebooting the AL205B/R.
  • Improve handling of cases where firmware file extensions aren't correct when upgrading.
v1.2.0May 17, 2020
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  • Fixed an issue where the repeater would corrupt MANT PDUs when adding an application layer time stamp.
  • Implement IND API 57: Repeater Add Path Override which forces the addition of path information regardless of the "Add Path" flag in the incomming MANT PDU.
  • Fixed an issue with A2Control that would prevent serial numbers from being displayed.
v1.1.0May 16, 2020
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  • Add a random delay before transmitting in ALOHA mode, moving away from the AirLink specification but placing the AL205B/R more in-line with other ALERT2 devices and improving operation on a TDMA network.
  • Change "Report Rejected Messages" from API #57 to API #58; make it apply globally instead of per address list.
  • Report GPS signal strength in A2Control; move GPS and clock control to "Globe" pane.
  • Add "Reboot Device" button to A2Control; add "Reboot Device" API (#7023).
  • Fixed a bug in A2Control that would not allow setting hop limit to 0.
v1.0.4May 15, 2020
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  • Fixed an issue that would prevent demo units from connecting with A2Control on windows.
  • Add Application PDU ID and Application Layer test flag fields to A2Control.
v1.0.3May 14, 2020
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  • Fixed a bug with the one radio RX/TX setting that would cause the encoder to never transmit.
v1.0.2May 13, 2020
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  • Enable manually starting a GPS sync cycle on the AL205B/R.
  • Allow manually setting clock on AL205B/R from clock on PC.
  • Improve A2Control performance with large number of messages in the message list.
  • Fixed an issue where repeater pass and reject lists would not work correctly with some settings.
  • Fixed an issue where the GPS clock would turn off before it should when leap seconds weren't known.
  • Update A2Control to support baud rate autodetection.
  • Add transmit page to A2Control that allows users to send a generic GSR or a status message, as well as view the current status values.
  • Update status report format to match status report proposal to ALERT2 TWG.
  • Fixed an issue where network connections were reset when they were droppedby the remote end.
  • Improve accuracy of battery voltage monitor.
v0.13.3May 12, 2020
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  • Fixed a rare issue which would cause the device to not transmit messages.
v0.13.2May 11, 2020
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  • Fixed an issue that would cause the GPS to turn off prematurely if leap seconds weren't known, causing clock sync to fail.
  • Update the minimum TDMA slot padding to be 12ms.
  • Add a config option allowing users to decide how slot overruns are handled. Options are are: buffering (LIFO), dropping messages, or allowing overrun.
  • Attempt to repair corrupted file systems on SD cards caused by power failure on system power up.
v0.13.2May 10, 2020
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  • Fixed an issue with outgoing IP connections where connections were not getting cleaned up properly when the network string changed.
v.13.0May 9, 2020
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  • Revert sending a 6-byte timestamp in the binary decoder output stream to a 4-byte POSIX timestamp; add a new TLV (125) with 6-byte timestamp in a different format (milliseconds since the unix epoch).
  • Move "firmware version" TLV type from 10 to 150.
  • Add firmware version checks to A2Control.
  • Disable IP-fields in A2Control when DHCP is enabled.
v0.12.5May 8, 2020
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  • Add missing ALERT2 prefix to binary messages sent via IP.
v0.12.4May 7, 2020
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  • Improve time quality from initial GPS lock. Fixed an issue where the GPS would remain on longer than it should.
v0.12.3May 6, 2020
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  • Fixed an issue that could cause an invalid time to be reported if the clock changed significantly (e.g., got sync for the first time) after receiving, but before transmitting, ALERT concentration data.
  • Performance improvements.
  • Fixed an issue with decoding multiple encrypted PDUs. Modify endianness of encryption hash function to match spec.
v0.12.2May 5, 2020
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  • Allow setting status report interval in minutes instead of hours.
  • Transmit status update on change in GPS status.
  • Allow user configuration of status report offset (in minutes).
v0.12.1May 4, 2020
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  • Fixed a critical issue that would cause the decoder to hang in the event of a buffer overrun.
v0.12.0May 3, 2020
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  • Updates to support the latest rev of the AL205B/R hardware.
v0.11.5May 2, 2020
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  • Improve clarity of logging from gps_clock service.
  • Include ALERT concentration messages in local output, much like ALERT2 messages sent from the device.
  • Fixed an issue with ip forwarding that was causing the AL205B/R to drop connections erroneously.
  • Store system logs on SD card; make them available via SFTP.
v0.11.4May 1, 2020
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  • Fixed an issue where the time reported via the IND API (type 126) was off by one day.
  • Fixed an issue that caused the GPS to remain active when using NTP as the clock source.
  • Cosmetic changes to A2Control.