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1.5 Assisted GPS (A-GPS)

Supply of aiding information like ephemeris, almanac, rough last position and time and satellite status and an optional time synchronization signal will reduce time to first fix significantly and improve the acquisition

sensitivity. All NEO-6 modules support the u-blox AssistNow Online and AssistNow Offline A-GPS services and are OMA SUPL compliant.

1.6 AssistNow Autonomous

AssistNow Autonomous provides functionality similar to Assisted-GPS without the need for a host or external network connection. Based on previously broadcast satellite ephemeris data downloaded to and stored by the GPS receiver, AssistNow Autonomous automatically generates accurate satellite orbital data (“AssistNow Autonomous data”) that is usable for future GPS position fixes. AssistNow Autonomous data is reliable for up to 3 days after initial capture. u-blox’ AssistNow Autonomous benefits are: Faster position fix

No connectivity required Complementary with AssistNow Online and Offline services No integration effort, calculations are done in the background For more details see the u-blox 6 Receiver Description including Protocol Specification [2].

1.12.3 Serial Peripheral Interface (SPI)

The SPI interface allows for the connection of external devices with a serial interface, e.g. serial flash to save

configuration and AssistNow Offline A-GPS data or to interface to a host CPU. The interface can be operated in

master or slave mode. In master mode, one chip select signal is available to select external slaves. In slave mode a

single chip select signal enables communication with the host.