USGlobalsat EM-318-02 User Manual
Page 12
EM-318-02
Specifications are subject to be changed without notice.
Page 12 of 16
Version 1.2.1
ZDA—PPS timing message (synchronized to PPS)
Outputs the time associated with the current 1 PPS pulse. Each message is output within a
few hundred ms after the 1 PPS pulse is output and tells the time of the pulse that just
occurred
Table B-10 contains the values for the following example:
$GPZDA,181813,14,10,2003,00,00*4F
Table B-10 ZDA Data Format
Name
Example
Units
Description
Message ID
$GPZDA
ZDA protocol header
UTC time
181813
Either using valid IONO/UTC or
estimated from default leap seconds
Day 14
01
TO
31
Month 10
01
TO
12
Year
2003
1980 to 2079
Local zone hour
00
knots
Offset from UTC(set to 00)
Local zone minutes
00
Offset from UTC(set to 00)
Checksum
End of message termination
■
NMEA Input Command
A.) Set Serial Port ID:100 Set PORTA parameters and protocol
This command message is used to set the protocol (SiRF Binary, NMEA, or USER1) and/or the
communication parameters (baud, data bits, stop bits, parity). Generally, this command is utilize to
switch the GPS module back to SiRF Binary protocol mode, where an extensive message commands
are readily available. In example, whenever users are interested in altering navigation parameters, a
valid message sent and is receive by the recipient module, the new parameters will be stored in
battery backed SRAM and then the receiver will restart using the saved parameters.
Format:
$PSRF100,
0=SiRF Binary, 1=NMEA, 4=USER1
1200, 2400, 4800, 9600, 19200, 38400
0,1
0=None, 1=Odd, 2=Even
Example 1: Switch to SiRF Binary protocol at 9600,8,N,1
$PSRF100,0,9600,8,1,0*0C
Example 2: Switch to User1 protocol at 38400,8,N,1