Multiple position sources

[Lerk]

As a carry-on user in multiple aircraft I have recently upgraded my classic into a Rosetta-esque case.
I’m contemplating putting an externally accessible USB port on the case to allow me to connect the gps dongle remotely (or a dedicated mouse, but I already have a spare standard dongle) for aircraft where placement makes it harder to get a good gps reception.

What would the RPi make of having two dongles connected at the same time?
Would it run both (I assume this would cause an issue due to location discrepancy)
Would it start one in preference to the other?

My gut feel is that it will grab the first to wake up and communicate or by port number.
I will be having a play at this later on, but wondering if anyone else knows first!

And Yes, I could just remove the accessory cover, remove the dongle and plug in the mouse, but I’m trying to make something a bit slicker than that!

[exfirepro]

Hi Lerk,

Funny you should mention running 2x GPS dongles at the same time. I have to admit to discovering after a recent flight that, presumably distracted while putting my Rosetta in the plane, I had inadvertently plugged in my fixed GPS mouse without first removing the standard GPS dongle.

I have to say the unit certainly appeared to work fine and I didn’t actually notice anything untoward at all until I came to remove the unit from the plane on return to base. Oops     

I do however know that following disappointing trials back in 2016 using a directly connected FlarmMouse as an external gps source for PAW, Lee configured the software such that if a single (suitable) GPS Source is present, PAW would try to use it but that if a ‘Genuine PAW GPS’ was then detected (added), PAW would automatically prioritise and use the ‘known’ PAW source rather than the ‘interloper’. As far as I know that protocol still remains in place. I’d have to ask Lee re how the system would prioritise between 2 x ‘Genuine PAW’ modules. I will give it a (deliberate) try myself when I get a chance and report back.

Best Regards

Peter

[Lerk]

Looks like it picks up what is there in port order, so that makes it very easy!
My trials showed the two devices but it always booted to the left hand device.
Unplugging or covering the right hand device showed no change in gps status, where the same action on the left hand device caused gps to fail or satellites reduce.

So I’ll be setting up as below:
External USB port     Ublox 7 GPS dongle
DVB-T dongle           WiFi dongle

With no mouse connected to the external port it will boot on the internal device, but if I plug in a mouse before powering up, it will use that!

[Lerk]

[Admin]

This is determined by the OS, if both are plugged in At the same time there should be a repeatable order, it will be the first assigned to the device driver

Thx
Lee