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4.9 System Functions
4.9.1 Reset Options
The ANTARIS
®
4 GPS Technology distinguishes between four types of reset. An external hardware reset (by
pulling open drain RESET_N pin low), two resets are controlled software resets and one is an asynchronous
software reset, which are used to shut down and restart parts or e
The forced reset performs an immediate hardware reset similar exter ard reset.
Upon every software reset, it’s possible to define the type of start-up scen (Hotst rt, Warmstart, Coldstart).
This start-up scenario defines which GPS data is reused and wh is cleared .g. epheme ed
for a Warmstart).
4.9.1.1 Controlled Reset
The Controlled Reset waits until the system is in the background task (all ta e It the
Stop Event and a System Stop Event. After that the software is started aga is ns that the configuration
from BBR (battery backup RAM) or Flash (depending on the firm d) loa
4.9.1.2 Controlled GPS only Reset
The Controlled GPS only Reset waits until all GPS Tasks e idle (not running or pending). It then resets the
Navigation and Tracking Engine and starts them again. The system is not fully restarted from scratch.
The Forced Reset is an asynchronous reset that immediately stops all tasks that are running and resets the
hardware. No System Stop or GPS Stop Event is sent. This reset is equivalent to an externally supplied reset
gnal.
4.9.2 RESET_N - Reset signal generation and use
ected to VCC to RESET the GPS receiver, when the
supply voltage drops below 2.4V.
the whol receiver.
to the nal h ware
ario a
ich (e the ris data is clear
sks ar idle). n broadcasts a GPS
in. Th mea
ware use is re ded.
ar
4.9.1.3 Forced Reset (Watchdog)
si
All ANTARIS
®
4 modules contain a Voltage detector conn
ATR062x
VCC
Voltage
Supervisor
VCC
LDO
1.8 V
to internal
RESET:
ATR0621
and FLASH
RESET_N
Voltage
Detector
one can apply external logic to drive the RESET_N signal low to activate
. applicati of re
Figure 94: RESET generation
RESET_N is an open drain I/O pin, thus
a hardware reset of the system In most ons, the use the RESET_N pin is not requi d since
ANTARIS 4 GPS modules contain an internal reset chip. Leave RESET_N unconnected if not used.
GPS Modules - System Integration Manual (SIM) (incl. Reference Design) Receiver Description
GPS.G4-MS4-05007-A1 Page 121