RE: nRF9160 GNSS solution retention

Håkon Alseth — Fri, 05 Feb 2021 13:53:49 GMT

Hi,

[quote user=""]1) RTC maintained as long as Vdd1/Vdd2 is present on module[/quote]

As long as the modem is active, the time is kept. If you turn off the modem, you will also stop any running clocks.

[quote user=""]2) Does GNSS receiver maintain its own RTC or share with M33?[/quote]

The modem and application is separated. They do not share any specific peripherals, but clock sources do source both the modem and the application.

[quote user=""]3) Solution information is stored in non-volatile, as indicated below, and will survive disruptions to Vdd1/Vdd2?[/quote]

As long as you have gotten to the point of successfully downloaded the ephemerides, almanac, etc; it should be stored and loaded after a reset, provided that the delete_mask bits isn't populated:

 *          - Bit 0 denotes ephemerides data.
 *          - Bit 1 denotes almanac data (excluding leap second and ionospheric correction parameters).
 *          - Bit 2 denotes ionospheric correction parameters data.
 *          - Bit 3 denotes last good fix (the last position) data.
 *          - Bit 4 denotes GPS time-of-week (TOW) data.
 *          - Bit 5 denotes GPS week number data.
 *          - Bit 6 denotes leap second (UTC parameters) data.
 *          - Bit 7 denotes local clock (TCXO) frequency offset data.

Kind regards,

Håkon