The Mars Soiling Sensor firmware, Atonometrics part number 500079, is updated periodically for new features and improvements. Release notes for the most recent versions are shown below.


To download the latest firmware version, see Mars Firmware Update.


Version 5501, October 2021

  • Fixed an issue that could cause the unit to stop performing analyses, requiring a reboot
  • Fixed an issue that could cause the unit to not respond at its programmed IP address if booted without the Ethernet cable connected


Version R5430, August 2021

  • Fixed an issue that could cause the IP address to appear blank on the user interface
  • Other Bug fixes and improvements


Version R5381, July 2021

  • Added a feature that allows Mars to operate automatically without the user having to set location or maintain the clock. Dependence on Latitude, Longitude, and Clock time have been eliminated.
  • New units arriving from the factory will read transmission loss ~0, instead of NAN.
  • Other bug fixes and improvements


Version R5124, May 2021

  • Modbus RTU now supports 1s scan rate
  • Shortened timeout requirement on Modbus RTU to 500ms, delay between polls to 30ms


Version R5073, March 2021

  • Added a help message to the web interface for common setup issues.
  • Added a feature that reduces fluctuations in daily measurements.
  • Eliminated 4800 baud rate.


Version R4644, January 2021

  • Fixed an issue that prevented operation with some serial data formats in Modbus RTU.


Version R4629, September 2020

  • Bug fixes and improvements.


Version R4605, July 2020

  • Fixed an issue affecting some units with serial number >15020.
  • Bug fixes and improvements.


Version R4483, November 2019

  • Bug fixes and improvements.


Version R4467, September 2019

  • Added a feature to detect clock errors.
  • Bug fixes and improvements.


Version R4395, July 2019

  • Fixed an issue that could make unit unresponsive after power interruptions.
  • Added support for Network Time Protocol (NTP) synchronization of clock.
  • Added support for baud rate 38400 in Modbus RTU.
  • Bug fixes and improvements.


Version R4363, February 2019

  • Improved the software installer.
  • Added ability for user configuration of IP gateway and subnet.
  • Bug fixes and improvements.