MAX-M10M - Integration manual
Almanac, ionosphere, UTC correction, and satellite health data are transmitted by all satellites
simultaneously. Therefore these parameters can be downloaded when a single satellite is tracked
with a sufficiently high C/N0.
Allowing more ephemerides to be downloaded before going into the "POT" or the "Inactive for update"
state can help improve the quality of the fixes and reduce the number of wake ups needed to
download ephemerides at the cost of extra time in the "Acquisition" state (only when an inadequate
number of ephemerides are downloaded from tracked satellites).
3.6.3 Backup modes
A backup mode is an inactive state where the power consumption is reduced to a fraction of that
in operating modes. The receiver maintains time information and navigation data to speed up the
receiver restart after backup or standby mode.
The MAX-M10M supports two backup modes: hardware backup mode and software standby mode.
3.6.3.1 Hardware backup mode
The hardware backup mode allows entering a backup state and resuming operation by switching the
main power supplies on and off while maintaining a V_BCKP supply via, e.g. a battery. The receiver
enters hardware backup mode if the VCC and V_IO supplies are removed.
V_BCKP must be supplied to maintain the backup domain (BBR and RTC) to allow better TTFF,
accuracy, availability and power consumption at the next startup compared with a cold start. As
V_IO is not supplied, the PIOs cannot be driven by an external host processor. If driving of the PIOs
cannot be avoided, buffers are required for isolating the PIOs.
3.6.3.2 Software standby mode
Software standby mode is entered using the UBX-RXM-PMREQ message. V_IO and VCC must be
supplied, however VCC supply is internally disabled to save power. The V_IO supply maintains the
battery-backed RAM (BBR), RTC, and PIOs.
Entering the software standby mode clears the RAM memory including the receiver configuration.
To maintain the configuration, store it on both RAM and layers.
The software standby mode can be set for a specific duration, or until the receiver is woken up by
a signal at a wake-up source defined in UBX-RXM-PMREQ. The possible wake-up sources are UART
RX, EXTINT, and/or SPI CS pin. Refer to the interface description [
] for more information on the
UBX-RXM-PMREQ message. A system reset with the RESET_N signal also terminates the software
standby mode, clears the BBR content and restarts the receiver.
As V_IO is supplied, the PIOs can be driven by an external host processor. No buffers are required for
isolating the PIOs, which reduces cost.
The "force" flag must be set in UBX-RXM-PMREQ to enter software standby mode.
V_BCKP should be left open if not used.
UBX-22038241 - R02
3 Receiver functionality
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