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AL200 ALERT & ALERT2 OS

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

AL200 ALERT & ALERT2 OS

v6.08

Current AL200 operating system for ALERT and ALERT2. Requires the Device Configuration Utility to update the operating system in the AL200.

These current versions includes bug fixes and improvements to their prior versions and is recommended for all users.

Operating System  Version
ALERT 1.0
ALERT2 6.08

Revision History

v6.08December 9, 2025
  • Make TBR accumulator 2 bytes all the time.
  • Fix issue where old tips in queue caused all tip history to be dumpt.
  • Fixed issue where P1 would report as GSR sometimes.
  • Fixed issue with periods of nondecodeable frames.
  • Fixed missing service request without sdi12debug.
  • Change modulation gain to a much more linear software model.
  • Allow for long SDI12 replies.
  • Prettier printout for multiline sensor replies.
  • Stopped stop_te from rarely dropping a time event.
  • Add resilience timeout to red LED state machine.
  • Add time event loss detection.
  • Address possible rare issue where red serial led stays on.
  • Expanded SDI-12 interactive mode, added visibility for non measurement commands, added new command for full manual interaction.
  • Extended sdi12 command length, 100 characters should be fine.
  • Audio modulation voltage within 5% of selected setting, 15mv on 400mv, used code from AL200X for AL200, improved it and upgraded AL200X.
  • Fixed tone for button press, power was not turned on.
  • Dealt with carrier time = 0ms, check for zero and skip carrier state.
  • Found a lost event.
  • Fix issue where RMC gap occurs and a factory reset is sent.
  • fix issue where old tips in queue caused all tip history to be dumpt.
  • fixed issue where P1 would report as GSR sometimes.
  • fixed issue with periods of nondecodeable frames.
  • fixed missing service request without sdi12debug.
  • change modulation gain to a much more linear software model.
  • allow for long SDI12 replies.
  • prettier printout for multiline sensor replies.
  • stopped stop_te from rarely dropping a time event.
  • add resilience timeout to red LED state machine.
  • add time event loss detection.
  • address possible rare issue where red serial led stays on.
  • found a lost event.
v4.0December 1, 2023
  • New Feature
    The firmware for the AL200 has been completely refactored from the ground up. It no longer relies on code libraries from other ALERT2 manufacturers.
  • New Feature
    The API used in the AL200 now follows the specifications outlined in the ALERT2 IND API Specification Version 2.0 as released by the ALERT2 Technical Working Group dated June 2020.
  • New Feature
    250 millisecond slots are now supported.
  • New Feature
    Encryption of ALERT2 messages is now supported.
  • New Feature
    Allows selection of Test Flag functionality when Device Configuration Utility is connected to the AL200.
  • New Feature
    Allows selection of Forward Error Correction to increase data throughput or shorten slot requirement for good RF paths.
  • Minor
    GPS syncing and Clock Status stability has been improved.
  • Minor
    SDI-12 sensor support has been improved.
  • Minor
    SDI-12 sensor monitoring via Device Configuration Utility has been improved.
  • Minor
    Transmissions can now be set to start at the beginning of the slot (per industry common default) or centered (previous behavior).
  • (Depreciated) No longer supports ALERT concentration.
  • (Depreciated) No longer supports ALERT2 Version 1.0 API commands.
v4.0May 8, 2020
  • Initial release of the AL200 operating system for ALERT and ALERT2.
v03December 11, 2014
  • Changed muxing of 100 ohm resistor so that it is always switched in when configured for 4 to 20 mA sensor input. Previously, it was only switched in during the measurement.
  • Changed ADC SPI clock frequency so that it was always less than specified maximum.
  • Fixed timing bug that could have resulted in a missed transmission.