Re: COEX GPS (model UBX-M8030 IC) on Raspberry Pi 4 Model B 2018 connection issues

[Gary E. Miller]

Yo Aranza!

On Thu, 22 Jul 2021 17:44:22 -0700
Aranza Shaccid Leon <leon18@pnw.edu> wrote:

> Just as a quick clarification of my current situation:
> 1) I have the GPS connected to the flight controller with a UART
> connection and the flight controller is connected to my RPi via a
> USB. This is how I'm supposed to have it connected.

That was as I understood.

> 2) I disconnected the GPS from the flight controller, connected it to
> the RPi with a USB and inserted one line of udev rules in order for
> this connection to work.

Except, as we have seen, it does not.

> If I have the GPS connected to both the
> flight controller (UART connection) and the RPi (USB connection) the
> program will not run.

If by "program" you mean gpsd, then facts not in evidence.  If "program"
means something else, then that is new info.

How about we jsut get gpsd working first?

> Using gpsd -n /dev/ttyACM1 and then cgps in root did start the
> program and it did gather data.

Unclear what you mean by "program" and by "gather data".

Did cgps give you a good fix and time?

More important, what do you feel is now NOT working, as shown by this
most recent configuration.

> /usr/bin/lsof
> + lsof -iTCP:2947 -s TCP:LISTEN
> COMMAND PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
> systemd   1 root   58u  IPv6  11908     0t0  TCP localhost:gpsd (LISTEN)
> systemd   1 root   59u  IPv4  14690     0t0  TCP localhost:gpsd (LISTEN)
> gpsd    427 gpsd    4u  IPv6  11908     0t0  TCP localhost:gpsd (LISTEN)
> gpsd    427 gpsd    5u  IPv4  14690     0t0  TCP localhost:gpsd (LISTEN)

One agian, you have systemd(imwit) running on the gpsd port.  You
have NOT turned systemd(ipsy) off from controlling gpsd.

> + lsof -c gpsd
> + sed -nE 1p;/CHR|LISTEN/p
> COMMAND   PID USER   FD   TYPE     DEVICE SIZE/OFF  NODE NAME
> gpsd      427 gpsd    0u   CHR        1,3      0t0     5 /dev/null
> gpsd      427 gpsd    1u   CHR        1,3      0t0     5 /dev/null
> gpsd      427 gpsd    2u   CHR        1,3      0t0     5 /dev/null
> gpsd      427 gpsd    4u  IPv6      11908      0t0   TCP
> localhost:gpsd (LISTEN)
> gpsd      427 gpsd    5u  IPv4      14690      0t0   TCP
> localhost:gpsd (LISTEN)
> gpsd      427 gpsd    8u   CHR      166,0      0t0   378 /dev/ttyACM0

gpsd is listening on /dev/ttyACM0, but I thought your GPS was on /dev/ttyACM1??

> + ps ax
> + sed -nE 1p;/gpsd/p
>   PID TTY      STAT   TIME COMMAND
>   427 ?        S<s    0:00 /usr/sbin/gpsd /dev/ttyGPS

gpsd is missing the "-n" option.  That is NOT how I told you to start gpsd.

Confirm the /dev/ttyGPS is to /dev/ttyACM1 and that /dev/ttyACM1 is
the GPS?  Or is it /dev/ttyACM0?

> + gpspipe -w -n 2 -x 20
> gpspipe: invalid option -- 'x'

Here is where a recent version of gpspipe would ahve told me a lot.

>    Active: active (running) since Thu 2021-07-22 04:38:10 BST; 5min
> ago Listen: /var/run/gpsd.sock (Stream)
>            [::1]:2947 (Stream)
>            127.0.0.1:2947 (Stream)
>     Tasks: 0 (limit: 3737)
>    CGroup: /system.slice/gpsd.socket

That confirms you still have systemd(rama) controlling port 2947.

I can't help you if you continue to allow gpsd to run under systemd(racula).

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        gem@rellim.com  Tel:+1 541 382 8588

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    "If you can't measure it, you can't improve it." - Lord Kelvin

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