SEPTENTRIO AsteRx-m3, Руководство пользователя

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AsteRx-m3 OEM
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GNSS measurements are sampled) to that PPS input signal. TimeSync is typically used in
conjunction with REF IN (see section 2.6) to fully synchronize the receiver internal time
base with the time of an external clock.
Note that there is a delay of 15 to 50 ns between the PPS pulse at the TimeSync pin and
the receiver internal time base. That delay is dependent on the phase difference between
the 10 MHz frequency at the REF IN input and the PPS pulse at the TimeSync input. It is
possible to measure this delay by synchronizing the PPS output pulse (PPS1 pin) with the
internal time base, with the
setPPSParameters,,,,RxClock command.
2.9 General Purpose Output (GPx)
The GP1 and GP2 pins of the 60-pin connector are general purpose LVTTL digital outputs,
of which the level can be programmed with the
setGPIOFunctionality command.
During the first seconds after powering up the board, these pins are in tristate. Use an
external pull-down or pull-up resistor to have the desired level during boot.
The GPx pins can drive a maximum current of 10mA.
2.10 Standby Mode
In standby mode, all receiver functions are turned off and the power consumption is
significantly reduced (see section 2.3). There are two ways to enter standby mode:
1. By driving the nPDN pin low (pin#20 of the 30-pin connector). The receiver wakes
up when the nPDN pin level is high again (there is an internal pull-up).
2. By entering the “ exePowerMode, StandBy ” user command. To wake up, the nPDN
pin should be shortly driven low (at least for 50ms).
It is also possible to schedule automatic standby/wakeup periods using the
setWakeUpInterval command.
Note that entering standby mode takes a few seconds during which all running processes
are shutdown.
Warning: Do not drive a non-zero voltage into input pins (pins type “I”) when the receiver
is in standby. To be safe during standby, it is recommended to use the IO_EN signal of the
60-pin connector as enable for the drivers driving the input pins. The IO_EN signal is low
during standby.