Campbell Scientific GPS16X-HVS GPS Receiver - Manual (Page 25)

Appendix B. CR23X Wiring and
Programming
B.1 CR23X Connections
Reconfigure the receiver for 1200 baud using Garmin configuration software
available on Garmin’s website. Refer to TABLE B-1 to connect the GPS16X-
HVS directly to a CR23X datalogger.
TABLE B-1. CR23X Wiring
GPS16X-HVS CR23X Function
Red 12V Power In
Black Ground Power Ground
Yellow Ground Power Switch
White Control Port TXD
Gray Control Port PPS
Blue Ground in operation
Send data to receiver for
configuration
R
x
data
Shield Ground Shield
B.2 Programming
Program instruction 15 (P15) is used to read the NMEA $GPGGA string of
time and position data. Each iteration of P15 can either read the numeric fields
or read everything. When reading the numeric fields, such as time, latitude,
longitude and elevation, P15 requires non-numeric delimiters between data
points. The only available format of GPS data with delimiters is the NMEA
0183 format. Program instruction 15 (P15) reads serial data and discards non-
numeric values. All non-numeric values act as delimiters between numbers,
and decimal points can also act as delimiters. P15 can be used to import
everything in the string, character by character, and convert it to the decimal
equivalent. The decimal equivalent method is seldom used, and only when the
general area (hemisphere) is not known.
B.2.1 Program Execution Interval
When the PPS signal is used to trigger the read data function (P15), the
program table execution interval does not matter. Otherwise the timing
between the GPS16X-HVS output and the datalogger read must be considered.
Generally the execution interval can not be less than 2 seconds when the PPS
signal is not used.
B-1