CSI Wireless SBX-3, Reference Manual

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SBX-3 Reference Manual
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frequency and MSK rate of the last tuned station.
Figure 3-5 illustrates an example reset switch circuit.
External Reset
(Active Low)
Pin 20, J2
Switch
Figure 3-5 Reset Switch Circuit
3.5 SBX-3 Dual Serial Port Overview
The SBX-3 features two full duplex serial ports (Port 0 and Port 1). Use
of the second serial port is an option as the SBX-3 supports identical
functionality as its predecessor, the SBX-2 on Port 0.
The main purpose of the second serial port is to allow the continuous
flow of RTCM data from Port 0 to a GPS receiver while allowing
monitoring of SBX-3 performance via NMEA response messages on
Port 1. Separating RTCM differential data from NMEA status data when
output via the same serial port poses software integration challenges
and potential GPS RTCM reception conflicts.
3.5.1 Single Serial Port Operation
Some integration designs using the SBX-3 beacon receiver include a
micro-controller between the beacon and GPS receiver, to provide
enhanced communication and data parsing capability.
Within this type of integration, it is possible for the micro-controller to
command and query the beacon receiver and to parse NMEA response
strings from RTCM data without impeding the continuous flow of RTCM
data to the connected GPS sensor.