Change History

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GPS 17 software version 3.20

as of August 31, 2009

Changes made from version 3.10 to 3.20:

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

Changes made from version 3.00 to 3.10:

• Added process to monitor serial output in order to improve reliability.

Changes made from version 2.90 to 3.00:

• Reduced the number of channels allocated to searching in order to avoid overloading the CPU in difficult signal environments.

Changes made from version 2.80 to 2.90:

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

Changes made from version 2.70 to 2.80:

• Fixed potential loss of user settings in version 2.70.

Changes made from version 2.60 to 2.70:

• Added ability to turn low speed velocity masking on and off via a NMEA command.

Changes made from version 2.50 to 2.60:

• Added a new configurable feature called PPS Auto Off Modethat is disabled by default. Enabling this feature will turn off PPS output when the GPS fix is lost. Once a new fix is obtained PPS output will resume as normal.
• Corrected the sign on integrated cycles and carrier phase data in the RCV CPO message.

Changes made from version 2.40 to 2.50:

• Improved SBAS search and selection process.

Changes made from version 2.30 to 2.40:

• Updated for use with Garmin marine products.

Changes made from version 2.20 to 2.30:

• Validate altitude 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.
• Allow vertical filter to be disabled via the PGRMC sentence.
• Enhanced first fix processing.

Changes made from version 2.10 to 2.20:

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

Changes made from version 2.09 to 2.10:

• 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.
• Changed software version to 2.10.

Changes made from version 2.08 to 2.09:

• There were no functional changes made for this release. Modifications were made for manufacturing purposes only.

Changes made from version 2.07 to 2.08:

• Added automatic position averaging when stopped.
• Obsoleted position pinning. Position pinning remains off regardless of the PGRMC1 sentence command.
• Fixed problem with saving unit position in nonvol upon first fix.
• Change software version to 2.08.

Changes made from version 2.06 to 2.07:

• 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.
• Changed software version to 2.07.

Changes made from version 2.05 to 2.06:

• Addressed problem where NMEA sentences could become intermittent and unreliable when tracking two WAAS satellites simultaneously.
• Addressed problem where an 'extra' PPS pulse sometimes occurred in marginal signal environments.
• More work on problem where the unit sometimes reported an incorrect date and time in marginal signal environments when PPS is enabled.
• Changed software version to 2.06.

Changes made from version 2.04 to 2.05:

• Fix problem where unit sometimes reported an incorrect date and time in marginal signal environments when PPS is enabled.
• Changed software version to 2.05.

Changes made from version 2.03 to 2.04:

• Improve velocity accuracy when PPS is enabled.
• Changed software version to 2.04.