Testing of board version 1.0 is progressing well. I have identified a couple of issues and changes needed to make things easier for testing/debugging and enhance functionality (you can follow development in the repo). In the meantime I am re-evaluating some of the assumptions around the needed functionality (especially for the presence of RTC since we will be having a GPS so...) but would like the input on those from as many possible users as possible.

If you can spare 2 minutes, you could help me by going to this survey link:

>> forms.gle/6EQprC2uNaoJnSSL
and answer to some quick (choice) questions.

Thanks a lot in advance for everyone's input!

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Pierros Papadeas replied to the topic 'Astrohat - An open hardware RPi Hat for astronomy equipment' in the forum. 2 weeks ago

First board assembled with almost all components (since we have 3 identical double channels, I just soldered one to test it).

Initial tests look good, RPi4 booted OK, i2c devices responding, and channels seem to be switchable. Now I need to write a bit of software to drive the controllable voltage channel and test it :) More updates soon!



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Pierros Papadeas replied to the topic 'Astrohat - An open hardware RPi Hat for astronomy equipment' in the forum. 2 weeks ago

For switchable USBs there is an ongoing development process on RPi4 to make sure you can individually control the existing USBs on RPi4
github.com/raspberrypi/linux/issues/3079

As a general note adding a USB switch on the existing board would be not really feasible since we dont have a way to do that through the RPi hat-pinout. (and adding an extra cable to a USB port kinda defeats the purpose of a "hat")

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Pierros Papadeas replied to the topic 'Astrohat - An open hardware RPi Hat for astronomy equipment' in the forum. 2 weeks ago

After a bit of waiting for production and shipping the first version of the PCB and the components arrived!
Now I can start the assembly and hopefully start testing really soon. I will keep this thread updated with details.





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Pierros Papadeas replied to the topic 'Astrohat - An open hardware RPi Hat for astronomy equipment' in the forum. 2 months ago

Backside with some additional ports as requested:



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Pierros Papadeas replied to the topic 'Astrohat - An open hardware RPi Hat for astronomy equipment' in the forum. 2 months ago

kookoo_gr wrote: My 2 cents, i would prefer if one or a few of the 12v output ports could be adjusted from 5 to 15V. I power my equipment from a deep cycle battery and in order for my mount not to have the blinking LED which means it doesn't have sufficient voltage, and it affects guiding, and for my camera to perform with no issues i power my equipment with 13,5V. I still haven't see this feature in any power box which means i have to power the power box with 13,5v and then distribute those 13,5v via the power box to my equipment for proper functionality.


Some clarifications. The design as it is right now will supply to the channels whatever is supplied as VIN. Another 2 channels (Dew heaters) are PWM adjusted and 1 channel is LDO adjusted to 6-(VIN-something small). VIN in theory can be up to 16V, although I should probably protect the circuit at around 14.8-15V. Having an adjustable output that can go beyond the VIN would require a buck-boost circuitry that complicates the design at this point. If this is deemed critical, I would be happy to take a pass though.

This is a diagram to make it easier for people to see the main features:


As for active cooling I hope that the 5V port would be OK for a fan, but we really need to think about the fan placement. Having the boards at hand will help with that :)

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