Raspberry Pi Zero Flarm

[buchner1987]

Hi,
i have installed the image on a Raspberry pi Zero with deactivated flarm it works fine.
When i activate flarm the flarm process need to much CPU power after gps fix.
Has anyone an idea to reduce the needed CPU performance from the flarm service?
The CPU runs with 1,1 GHz.

Best regards

[b3nn0]

The Pi zero is not "officially" supported for exactly that reason. Because the OGN Stack demodulates 4 different protocols in software, CPU requirements are quite high. No way the Pi zero is strong enough to handle that.
Additionally, future versions will most likely use a 64 bit base image, which will then not run on the Zero at all, because it only has a 32 bit CPU.

[javedrahman]

Do you think the new pI zero 2 w will be strong enough? Being able to run stratux on the smaller form factor will be great.

[b3nn0]

In theory, I'd say yes. However, I received my PI Z2 earlier today and was not able to boot a 64 bit OS on it. Why that is I don't know, since I don't have a Mini-HDMI adapter to check. 32bit boots just fine.
If the form factor would really be smaller remains to be seen anyway, since you will need a USB hub (which has to be able to provide enough power).

[b3nn0]

After copying/renaming some dtb file on the boot partition, it now seems to boot and work correctly. CPU seems to be able to handle it easily, but it does seem to be a bit noisy.
I used a USB Hub hat, but was only able to get a GPS fix after plugging in an external antenna.

Note that I will most likely wait with the next version until RaspiOS Bullseye is released, so I'd expect the next version of Stratux to run on it without any modifications.

[javedrahman]

Perfect. I was wondering if the 512 MB of RAM would do.

The Zero4U USB hub attaches to the bottom of the pi0 and with some 180 degree USB type A adaptors It might be possible have the SDRs back to back on top the the usb hub. And then with a very short USB extension cable if we can have the GPS or TTGO t-beam somehow stacked on top of that. That should make the size quite a bit smaller than the current size with a regular sized pi. However, I agree, the power supply needs to be sorted out. If the USB hub can take a beefier power supply and in turn power the pi then that would work I think.

[b3nn0]

If you build something like that, I'd be happy to hear back from you with photos/experiences how well it works.