CSI Wireless SBX-3, Reference Manual

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SBX-3 Reference Manual
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2 T X - 2 T X -
4 R X - 4 R X - N M E A N M E A
RTCM RTCM
5 G N D 5 G N D G N D G N D
T X - T X -
R X - R X -
SBX-3 Evaluation
Module Rear Panel
GPS Receiver
1 T X + 1 T X + RTCM RTCM R X + R X +
7 R X + 7 R X + N M E A N M E A T X + T X +
Figure 2-4 Evaluation Module Interface, RS-422
For successful communications, the baud rate of the SBX-3 must be
set to match that of the GPS receiver. Section 3.7 describes the
default communication settings of the SBX-3. Refer to Section 5.6.2 to
change the baud rate of the SBX-3 using proprietary NMEA commands.
2.6.4 Changing the Interface Level
A majority of integrated GPS receiver products communicate at the
RS-232 level, similar to a PC computer. However, there are a number
of chart-plotting devices, incorporating GPS capabilities that operate at
the RS-422 interface level.
OEM GPS engines by themselves typically communicate with a 5V
HCMOS, TTL, or CMOS level.
The default communication level of
the Evaluation Module is RS-232C .
To switch from the default RS-232C communication level, you must
remove the back panel of the Evaluation Module to slide the carrier
board and SBX-3 out of the case. Always follow proper electrostatic
discharge precautions (ESD) when handling the receiver or its
components, outside of the enclosure. Such precautions include
proper grounding of personnel, tools, and the surface upon which the
receiver rests.