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So arrived and it looks very nicely made.
First impressions are just mechanical ...
On my Pi4, the height of the pillars is correct for the board, but the connection block is about 3mm too short, only just making contact with the header on the Pi4. I pushed the connector down 1.5mm from the MacArthur and it is better, but really, it needs a longer header.
The board contacts the USB sockets, so only the solder resist on the PCB prevents a short circuit of the tracks to the USB sockets, which will happen in time. A simple solution: put some PVC tape on the top of the USB sockets to prevent the board contacting thr bare metal.
The labelling of the connections/sockets is on the back of the board. Impossible to see once the board is mounted. If the connectors were just mounted on the back of the board instead of the top, the labelling could be placed on the top silkscreen layer, which woudl make it much easier to wire up without referring back to the manual. This could be done without any board changes, just the top silkscreen would need updating and the hand soldering of the connectors made with them mounted on the bottom layer. There is enough clearance between the Pi and the board to accommodate this.
Personally, I woudl be happy to lose the "seatalk" connection and gain a proper NMEA2000 plug, so I can connect with standard cables, but this is a minor point. I will have to find an NMEA2000 to bare wires cable.
Last question: where can I buy the IMU seen in the manual?
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Thank you for the detailed feedback! 
(2023-04-21, 02:14 PM)rszemeti Wrote: On my Pi4, the height of the pillars is correct for the board, but the connection block is about 3mm too short, only just making contact with the header on the Pi4. I pushed the connector down 1.5mm from the MacArthur and it is better, but really, it needs a longer header.
I know that the stacking header situation is unsatisfactory. "Extra-long headers" will have a gap under the HAT, with only the stand-offs ensuring proper mounting height. The correct headers would be the "double-shrouded" stacking headers available from Adafruit, Pimoroni, PiHut, etc. If anyone knows a reasonably priced source for bulk quantities of these, please let us know.
Quote:The board contacts the USB sockets, so only the solder resist on the PCB prevents a short circuit of the tracks to the USB sockets, which will happen in time. A simple solution: put some PVC tape on the top of the USB sockets to prevent the board contacting thr bare metal.
The labelling of the connections/sockets is on the back of the board. Impossible to see once the board is mounted. If the connectors were just mounted on the back of the board instead of the top, the labelling could be placed on the top silkscreen layer, which woudl make it much easier to wire up without referring back to the manual. This could be done without any board changes, just the top silkscreen would need updating and the hand soldering of the connectors made with them mounted on the bottom layer. There is enough clearance between the Pi and the board to accommodate this.
Having through-hole solder joints on both sides of the PCB is an issue for manufacturing. In volume production these are not hand-soldered but done with a selective soldering machine. Besides that, I'd be worried about clearance above display and camera connectors.
But you are right about the labels being hidden. One idea is to include a sheet with stickers that would go on all the connectors, including the detachable screw terminals. As a bonus, that sheet could also include a sticker for extra insulation on top of the Ethernet and USB connectors
Quote:Personally, I woudl be happy to lose the "seatalk" connection and gain a proper NMEA2000 plug, so I can connect with standard cables, but this is a minor point. I will have to find an NMEA2000 to bare wires cable.
There are several reasons we decided do go with a screw terminal for NMEA 2000:
1. Size: Compatible connectors occupy an area of 20x15mm on the PCB and are 17 mm high, compared to 8x7x7 mm for the screw terminal
2. Versatility: While NMEA 2000 is just CAN, some vendors have gone with different connectors for their own implementation (for example SeaTalkNG and Simnet). Plus the screw terminal is easier to use for DIY CAN projects.
3. Cost: The connector required for NMEA2000 is relatively expensive ($8-$10 in 100 quantity)
Quote:Last question: where can I buy the IMU seen in the manual?
I will leave that question to Sailoog.
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Points noted, makes sense. I made a fresh install of OpenPlotter and so far, no problems. I have it running already with the Maiana I built producing GPS, all is good!
You are right about the display connector would be a problem with sockets on the backside, I do not use that, my 10" touchscreen is connected my HDMI.
This will replace my PicanM board ... and also the "second Pi" that had the Moitessier hat ... the Pican and Moitessier are not compatible, so I was using 2 Pi's ... and lots of problems  ... already this looks great!
The fixed 12V and switched 12V is a great feature, I didn't reallise that was part of it, very useful to be able to nicely close the pi!
The only part missing now to replace the Moitessier is the IMU, the air pressure is not so important. Thanks for a great product ... I hope to have it on the boat in 1 week and will report back.
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2023-04-22, 06:08 PM
(This post was last modified: 2023-04-22, 06:09 PM by rszemeti.)
One thing I noticed, the power off feature ... I had a couple of occasions where it did not power off, written on the screen was "plymouth-shutdown.service" in bottom left, but after 10 minutes, it had not shut down.
I also noticed that if you shut the system by the switched 12V and OpenCPN is active, next time it will warn you about "do you want to start OpenCPN wihtout plugins" etc so I guess whatever script is running after the switched 12V is removed is not cleanly closing OpenCPN? Is it possible to script this to cleanly close OpenCPN?
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(2023-04-21, 02:14 PM)rszemeti Wrote: Last question: where can I buy the IMU seen in the manual?
We are using this one for development: https://www.aliexpress.com/item/4000910277147.html
Fully supported by pypilot.
Another reason for screw terminals instead of "standar" NMEA 2000 conector:
4. They transmit more mechanical stress to the board.
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(2023-04-22, 06:08 PM)rszemeti Wrote: One thing I noticed, the power off feature ... I had a couple of occasions where it did not power off, written on the screen was "plymouth-shutdown.service" in bottom left, but after 10 minutes, it had not shut down.
That is weird. Never seen under development. For some reason the shutdown is not completed and the Raspberry never sends the OK to the HAT that does not reply with the poweroff order. Some rebel applications can make the shutdown process longer but 10 minutes is too much. Do you have any other HAT or something connected to GPIO21 and GPIO26? Next time leave the system longer than 10 minutes if you can.
(2023-04-22, 06:08 PM)rszemeti Wrote: I also noticed that if you shut the system by the switched 12V and OpenCPN is active, next time it will warn you about "do you want to start OpenCPN wihtout plugins" etc so I guess whatever script is running after the switched 12V is removed is not cleanly closing OpenCPN? Is it possible to script this to cleanly close OpenCPN?
That is an opencpn feature I do not like either. The HAT sends a signal to the Raspberry to do a normal shutdown and any app should be closed "cleanly" but opencpn interprets any external closing order as an unexpected closing. You can ignore that message and it will disappear after few seconds.
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(2023-04-24, 03:10 PM)Sailoog Wrote: Do you have any other HAT or something connected to GPIO21 and GPIO26? Next time leave the system longer than 10 minutes if you can.
No, no other hats .. I will leave it longer next time, in case something is blocking ... I think I will put an LED from the 5V to the front panel ... when I remove the +12V switched, it stops my display, so I cannot see if the Pi is still active. I only noticed it was active because I am testing on my bench supply and the current was still 250mA ... I will wait longer next time. I like the idea of a nice, clean closedown of the Pi ... but it must be reliable or I will find my battery is dead. A useful feature might be an external "shutdown in progress" LED that can be mounted on the front panel ... there are spare ports that I can use for this.
(2023-04-24, 03:10 PM)Sailoog Wrote: That is an opencpn feature I do not like either. The HAT sends a signal to the Raspberry to do a normal shutdown and any app should be closed "cleanly" but opencpn interprets any external closing order as an unexpected closing. You can ignore that message and it will disappear after few seconds.
I would be happy never to see that message again ... I do not really trust OpenCPN with closing ... too many times it has lost its settings ... I leave the settings chmod 444 and I had no trouble for more than 1 year ...
I have ordered the IMU, I had some troubles with the one on the Moitessier, I think because it was too close to some other wiring ... I hope this is in a better place ... or I can make an extender.
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Agree, the power off feature must be completely reliable. We had 100% of successful attempts during development and testing.
Just to be sure, if you do a manual shutdown without removing 12V SW the MAIANA will keep working silently. That has happened to me a lot of times, everything was off but I could see the current flowing from the power supply. Could that be what happened to you?
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No, the Maiana draws just a few tens of milliamps ... this was drawing 200+mA and when I powered the monitor back on I could see the words "plymouth-shutdown.service" on the otherwise black screen ... its not done it again, if it does, I'll dump the log directory.
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OK, thanks. The 5V LED in your enclosure sounds like a good idea to confirm everything is off.
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