[gpsd-users] Set up for time sync and separate serial port use

[Pittman, Randall]

Hi,

 

I have a python app that connects to my GPS Compass (Hemisphere Vector V103), sets it up to send certain messages, and then records the messages as they come in and parses them with the pynmea2 library. However, I’d also like to sync the system clock (CentOS 7) with the 1PPS signal from the GPS. Here is how I’m considering doing this, but I have no idea if it will work:

 

serial connection      38400 baud, GPZDA @ 20Hz, PASHR @ 20 Hz, GPGGA @ 20 Hz, GPROT @ 5 Hz

from V103 with 1PPS

__   on DCD line

  \                                   ________

  |                                  /

  |==================================|  USB-to-serial adapter >>

  |    \\                            \________ Used by Python app

__/     \\

         \\

          \\

           \\                          __

            \\  Tap RX line,          /

             \\ Split off DCD line    |

              \=======================|  Serial port (ttyS0) >>

                                      |    used by gpsd for time sync

                                      \__

 

Will this work? What NMEA messages does gpsd need to work for time-sync? GPZDA only? My setup is currently outputting GPZDA at 20Hz

 

I guess an alternate approach could be to set up the message sending in my app and then is there any easy way to record all the message data with gpsd? I’m new to gpsd and in a bit of a time crunch. =( (no pun intended)

 

Thank you,

Randy

 

 

Randall Pittman

Faculty Research Assistant | School of Civil and Construction Engineering | Oregon State University

Location: 006 Covell Hall | Mailing: 101 Kearney Hall | Corvallis, OR 97331-2132

Office: 541-737-2102 | Mobile: 541-286-7896