Hello:
I'm using an Ubuntu 16.04 runtime with gpsd==3.9 Python3 module. What I'm trying to do is poll for new samples as they come in using the gpsd python client API - similar to gpspipe select I/O interface.
The unit I'm connecting to is a Trimble SPS585:
The connection is unfortunately over the Trimble's wireless interface (for the purposes of this conversation that can not change). The two strings I'm interested in are the RMC and GGA ones and both are set to 10Hz on the system in Kinematic mode.
There are a few examples on the web and a blurb in the man page but all of them are inconsistent with one another.
What my polling process does is in effect this:
trimble = gps.gps(host, port)
while True:
trimble.read()
nmea = trimble.data()
if nmea:
parse_nmeas(nmea) # Extract RMC/GGA
time.sleep(0.1) # Trimble set to 10Hz for RMC and GGA strings
This seems to work with the caveat that I'm seeing a lag issue, i.e. after X number of minutes (!?) the points start to have large gaps between them. And I'm wondering if the above code is somehow causing this? I just want to make sure I'm using the gpsd API correctly.
Thanks!
-aps