First Impressions

[Max1947]

Ciao @Sailoog, the safe shutdown didn't work and I had to do a clean install because the SD was gone.
 
Now I don't trust to turn off with the switch.
 
Let me know if I need to let you have more info and how to do it.  

[Sailoog]

Now is difficult to know what happened. My theory is that your configuration was not complete or wrong and you cut the power corrupting the SD.

Yours is a different case than rszemeti's. When you are at the "plymouth-shutdown.service" screen it is safe to cut the power, but you did it before then.

Do not be afraid of testing again please, this is a well tested feature and it should work. Make sure you have the configuration of the screenshot but use the switch only after a first reboot to apply changes. Make also sure that no other device or app is using GPIO21 and GPIO26.

[rszemeti]

Just as an update, I now have this installed on the vessel, Maiana is running well, the MacArthur HAT is providing GPS data over NMEA 0183 to the VHF, integrated with my NMEA2K network for depth/speed/wind and providing compass data from the IMU to the network too. OpenCPN is doing its thing ... and all is well in the world! Great product that has allowed me to go from a "2 pi" solution with a Moitessier and a Pican M to a single pi with a Macarthur hat.

So far, the "shutdown" issue has not shown itself again, but I really would like to have an LED that I could mount next to the display that comes on as shutdown begins and goes out when the device is truly powered down.

I still have to figure out the compass data ... which just like the compass on the Moitessier is prone to huge chnages in offset ... I got around this on the previous install by just mounting the box with the Moitessier on a single screw and when it booted and was massively out with the mag compass on the binnacle, I would just turn the whole box with the Moitessier and Pi around until they matched, easier than messing with the config. I have no idea why it does this, calibration is "locked", this IMU seems to behave the same ... sigh. No clue why, will play more with it.

[Sailoog]

Glad to read that, thanks for the update! That was the main goal: simplify.

We did not have any "failed" shutdown while development and that means hundreds of attempts. You already have the 5V and the 12V leds in the MacArthur. If these leds are hidden by a casing or some panels, you can add a LED + resistor to the 3.3V/GND pins. when the shutdown sequence is complete, it will turn off. You can also use 5V/GND pins or even the 1W connector, see 1W alternative uses in the manual.

Just in case, calibration should not be "locked". The system should be always re-calibrating.

[rszemeti]

Yes, thats a good idea, I'll consider adding an LED off the 5V rail ... what will probably happen is I grow confident in it and don't bother

I had the same "changing compass offsets" problem in the Moitessier and was told to make sure it was locked, or it would always be re-calibrating ... I'll try unlocking it and see if it improves ...