ET-314AC
High Performance GPS Engine Board
2010/4/1
- 17 -
C). Set DGPS Port ID: 102 Set PORT B parameters for DGPS input
This command is used to control the serial port used to receive RTCM differential corrections.
Differential receivers may output corrections using different communication parameters. If a
DGPS receiver is used that has different communication parameters, use this command to allow
the receiver to correctly decode the data. When a valid message is received, the parameters are
stored in battery-backed SRAM and the receiver restarts using the saved parameters.
Table B-5 contains the input values for the following example:
Set DGPS Port to 9600 baud, 8 data bits, 1 stop bit, no parity bit.
$PSRF102,9600,8,1,0*12
Table B-5 Set serial Port Data Format
Name Example
Units
Description
Message ID
$PSRF102
PSRF102 protocol header
Baud
9600
1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200
DataBits
8
8,7. Note that SiRF protocol is only valid for 8 Data bits
StopBits 1
0,1
Parity
0
0=None, 1=Odd, 2=Even
Checksum *12
<CR><LF>
End of message termination
D). Query/Rate Control ID: 103 Query standard NMEA message and/or set output rate
This command is used to control the output of standard NMEA messages GGA, GLL, GSA, GSV,
RMC, and VTG. It also controls the ZDA message in software that supports it. Using this
command message, standard NMEA messages may be polled once, or setup for periodic output.
Checksums may also be enabled or disabled depending on the needs of the receiving program.
NMEA message settings are saved in battery-backed memory for each entry when the message
is accepted.
Table B-6 contains the input values for the following example:
Query the GGA message with checksum enabled
$PSRF103,00,01,00,01*25
Table B-6 Query/Rate Control Data Format
Name Example
Unit
Description
Message
ID $PSRF103 PSRF103
protocol
header
Msg
00
Message to control. See Table B-7
