Change History

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GPS 17N software version 2.90

as of August 31, 2009

Changes made from version 2.80 to 2.90:

• Modified proprietary binary output data format to fix incorrect date/time calculation on some Garmin marine products.

Changes made from version 2.70 to 2.80:

• Fixed SBAS compatibility issue with Japanese MSAS system
• Drop WAAS satellites that are not transmitting useful data

Changes made from version 2.60 to 2.70:

• Improved SBAS search and selection process.

Changes made from version 2.40 to 2.60:

• Updated for use with Garmin marine products.

Changes made from version 2.30 to 2.40:

• Altitude is now validated during first-fix processing.
• Improved EPH during transition from non-differential fix to a differential fix.
• Added ability to turn position averaging on and off via a Garmin or NMEA command.
• Vertical filter in now allowed to be disabled via the PGRMC sentence.
• Enhanced first-fix processing.
• Changed software version to 2.40.

Changes made from version 2.20 to 2.30:

• Improved non-volatile memory storage of WAAS/EGNOS ionospheric mask corrections.

Changes made from version 2.11 to 2.20:

• Improved WAAS/EGNOS satellite selection algorithm to select the satellite with the most beneficial corrections given the unit's current position. Units will not use a WAAS/EGNOS satellite if the unit's current position is outside of a given WAAS/EGNOS satellite's service volume.

Changes made from version 2.10 to 2.11:

• Removed position pinning. Position pinning remains off regardless of the PGRMC1 sentence command.
• Fixed problem with saving unit position in nonvolatile memory upon first fix.

Changes made from version 2.09 to 2.10:

• Added automatic position averaging when stopped.

Changes made from version 2.08 to 2.09:

• Added support for ephemeris download.
• Fixed problems where leading zeros were not being transmitted in certain fields of GPRMC and GPVTG.
• Improve eph estimate for WAAS DGPS fixes.

Changes made from version 2.07 to 2.08:

• Made improvements to alleviate the 'LOST GPS FIX' messages that were occurring on the West Coast.

Changes made from version 2.06 to 2.07:

• Fixed problem where WAAS processing could cause the unit to lock up.

Changes made from version 2.05 to 2.06:

• Fixed problem where WAAS processing could cause the unit to lock up if tracking more than one WAAS satellite

Changes made from version 2.04 to 2.05:

• Implement better validity checking on dates to prevent the date from being incorrectly set far in the future.
• Improved NMEA sentence processing to prevent long dropouts in the NMEA sentence stream.