SAM-M8Q - Hardware Integration Manual
UBX-16018358 - R05
Production Information
Hardware description
Page 7 of 23
1.5
I/O pins
1.5.1
RESET_N: Reset
Driving
RESET_N
low activates a hardware reset of the system. Use this pin only to reset the module. Do not use
RESET_N
to turn the module on and off, since the reset state increases power consumption. The SAM-M8Q
RESET_N
pin is for input only.
The RTC time is also reset (but not BBR). Means the Hotstart performance will be degraded after a reset.
No additional capacitance should be added at
RESET_N
pin to GND (otherwise it could cause a reset at
startup).
1.5.2
EXTINT: External interrupt
EXTINT
is an external interrupt pin with fixed input voltage thresholds with respect to
VCC_IO
(see the
SAM-M8Q Data Sheet
[1]
for more information). It can be used for wake-up functions in Power Save Mode on
and for aiding. Leave open if unused, function is disabled by default.
Power Control
The power control feature allows overriding the automatic active/inactive cycle of Power Save Mode. The state of
the receiver can be controlled through the
EXTINT
pin. The receiver can also be forced OFF using
EXTINT
when
Power Save Mode is not active.
Frequency aiding
The
EXTINT
pin can be used to supply time or frequency aiding data to the receiver.
For time aiding, hardware time synchronization can be achieved by connecting an accurate time pulse to the
EXTINT
pin.
Frequency aiding can be implemented by connecting a periodic rectangular signal with a frequency up to 500
kHz and arbitrary duty cycle (low/high phase duration must not be shorter than 50 ns) to the
EXTINT
pin.
Provide the applied frequency value to the receiver using UBX messages.
1.5.3
TIMEPULSE
A configurable time pulse signal is available with SAM
‑
M8Q antenna module. By default, the time pulse signal is
configured to one pulse per second. For more information see the
u-blox 8 / u-blox M8 Receiver Description
Including Protocol Specification
[2]
.
1.5.4
SAFEBOOT_N
The
SAFEBOOT_N
pin is for future service, updates and reconfiguration.
