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    Unable to change Serial GPS baud rate

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    • stephenw10S Offline
      stephenw10 Netgate Administrator
      last edited by

      Yes I've seen similar behaviour to that before. If I recall correctly it was because you need to initialise the receiver in it's native baud rate to then use whatever speed you set.
      Are you initialising it at 4800 in one of the default settings?

      What are you seeing? What have you set? How are you testing?

      Steve

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      • S Offline
        scramjet36
        last edited by

        Previously, I've just used a USB GPS, so this straight RS-232 serial GPS with PPS is new for me. I was just using the "Generic" settings and also tried "Custom" but none keeps the baud rate selection.

        If I remove the serial cable and connect it up to a different machine, I can see the messages coming through just fine, so I know it's working.

        Here are the settings I am attempting, minus the baud rate being correct.

        2936c007-cedb-4823-b563-892de6536d38-image.png

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        • stephenw10S Offline
          stephenw10 Netgate Administrator
          last edited by

          Nothing in the advanced settings?

          Hmm, I remember hitting this and it was some chicken and egg style setting issue... 🤔

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          • S Offline
            scramjet36 @stephenw10
            last edited by

            @stephenw10 Nope, nothing in the advanced settings. The gps starts streaming messages immediately upon powering up and achieving the lock, so shouldn't be anything necessary in there (from what I can tell).

            Such a weird issue. Thanks for your help. I'll look at it more today as well and see if I can poke around.

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            • stephenw10S Offline
              stephenw10 Netgate Administrator
              last edited by

              Hmm, looks like a bug: https://forum.netgate.com/topic/152369/ntp-gps-settings-serial-port-speed

              That's fixed in 2.5.

              It is possible to set 9600 in 2.4.5p1 though, I have that running here.

              Try stopping the ntpd service then making the change.

              Steve

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              • S Offline
                scramjet36
                last edited by

                Interesting, thanks for the pointer. I will try and let you know how it goes.

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                • S Offline
                  scramjet36
                  last edited by

                  Stopping the service did not allow for the baud rate change. I'll update to 2.4.5_1 and see how it goes then.

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                  • S Offline
                    scramjet36
                    last edited by

                    I updated to 2.4.5_1 and am still unable to change baud rate. Everything else on that page can be changed except for the baud rate. Stopped the service and tried again post update, but still no dice.

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                    • stephenw10S Offline
                      stephenw10 Netgate Administrator
                      last edited by

                      Hmm, it's in 2.5 dev snapshots if you're able to run those.

                      Otherwise I would check the baud rate being set in the config file and what speed the actual device comes up at. It could just be a display bug.

                      Steve

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                      • S Offline
                        scramjet36
                        last edited by

                        I updated to 2.5 dev and nuked everything (no connectivity on any of the VLANs) so I've reinstalled 2.4.5_1 and reverted my config. I will try again with the GPS later. Thanks again for your help thus far with troubleshooting.

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                        • S Offline
                          scramjet36
                          last edited by

                          Also worth noting is that you were correct - before I reverted my config because all routing was broken and I had no connectivity except on my fallback OPT1 HW interface, I did check the GPS settings and was able to change to 9600. On 2.5x with the baud rate able to be changed, the GPS immediately started working and had a lock, with PPS working and all was well.

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