CSI Wireless DGPS MAX, Reference Manual

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DGPS MAX Reference Manual
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ground point in most instances will be the chassis of a vehicle. Other
grounds may provide acceptable performance. You should minimize the
overall length of the ground wire for best performance.
2.3.6 Connecting the DGPS MAX To External Devices
The DGPS MAX operates at the RS-232C interface level to communicate
with external data loggers, navigation systems, and other devices. It
features two data connectors on the rear panel, labeled ‘MAIN’ and ‘AUX’
to transmit and receive data (refer to Appendix B Interface Information).
MAIN is the primary interface port for differentially corrected GPS data.
The AUX port is a secondary port designed for input of external RTCM
correction data. In the case that an external differential source is required,
you may configure the DGPS MAX using the menu system to accept the
external correction data through the AUX port.
Both data ports are located at the back panel of the DGPS MAX and are a
DB9 socket connector. Table 2-2 and Table 2-3 provide pin-assignment
information for the DGPS MAX MAIN and AUX serial ports respectively.
Table 2-2 MAIN Pin-out, RS-232C Interface Level
Pin # Signal Description
2 TXD DGPS MAX NMEA 0183 and binary output
3 RXD DGPS MAX NMEA 0183 and binary input
5 Sig. Ground Signal return
9 1 PPS 1 Pulse per second timing output (HCMOS, rising edge
synch, 10 k
Ω
, 10 pF load)