u-blox LEA-M8S, Руководство по интеграции оборудования

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LEA-M8S / LEA-M8T - Hardware Integration Manual
UBX-13003140 - R07 Production Information Hardware description
Page 7 of 31
1.5 I/O pins
RESET_N: Reset input
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. With LEA-M8S and
LEA-M8T modules
RESET_N
is an input only.
RESET_N should be used only in critical situations to recover the system. The Real-Time Clock (RTC) will
also be reset and thus immediately afterwards the receiver cannot perform a Hot Start.
EXTINT: External interrupt
EXTINT
is an external interrupt pin with fixed input voltage thresholds with respect to VCC (see the LEA-M8S
Data Sheet
[1] or the
NEO/LEA-M8T Data Sheet
[2] for more information). It can be used for wake-up functions
in Power Save Mode on all u-blox M8 modules and for aiding. Leave open if unused.
SAFEBOOT_N
If the SAFEBOOT_N pin is “low” at start up, the u-blox M8 module starts in Safe Boot Mode and doesn’t begin
GNSS operation. The Safe Boot Mode can be used to recover from situations where the Flash has become
corrupted.
D_SEL: Interface select (LEA-M8T ONLY)
The D_SEL pin selects the available interfaces. SPI cannot be used simultaneously with UART/DDC.
If open, UART and DDC are available. If pulled low, the SPI interface is available. See the NEO/LEA-M8T Data
Sheet
[2].
Antenna Short circuit detection
The LEA-M8S and LEA-M8T modules include internal short circuit antenna detection. For more information, see
section 2.4.
Antenna open circuit detection
The LEA-M8S and LEA-M8T modules provide antenna open circuit detection (OCD) functionality over the
AADET_N pin.
AADET_N
is an input pin used to report whether an external circuit has detected an external antenna or not.
Low means an antenna has been detected (antenna consumes current), while high means no external antenna
has been detected (no current drawn). This functionality is by default disabled. See section 2.4.2.
TIMEPULSE 1
A configurable time pulse signal is available with all u-blox M8 modules. By default, the time pulse signal is
configured to 1 pulse per second. For more information, see the
u-blox M8 Receiver Description Including
Protocol Specification [3].
TIMEPULSE 2 (LEA-M8T only)
A configurable time pulse 2 signal is available on LEA-M8T module only. For more information see the u-blox M8
Receiver Description Including Protocol Specification [3].