Replicant

big chunks of the GSD4t protocol have been decoded at https://github.com/mnalis/gsd4t_parser
While something looking like GPS 50bps data have been extracted, it is still not enough to get a GPS fix.

Unfortunately, I've been unable to hack on it for some time, which probably won't improve as I'm not using that phone anymore.
So I'm documenting this in case somebody wants to take over and try to decode remaining bits)

I haven't tried it yet, but it looks like someone has a tutorial here on how to install the Guix package manager on Replicant: https://www.gnu.org/software/guix/blog/2018/guix-on-android/

They have https://www.gpsbabel.org/ packaged https://git.savannah.gnu.org/cgit/guix.git/tree/gnu/packages/gps.scm?id=v0.16.0-1464-g19d8f047c4#n40

I don't see gpsd packaged https://www.gnu.org/software/guix/packages/G/page/9/

Perhaps someone could write the needed recipe for it and add it as a package to Guix so that we could install it on Replicant if gpsbabel won't work to solve the ticket.

someone in termux upstream posted this:

"I can get the GPS data live stream out of android into termux with the app BlueNMEA, and sent that stream over cellular connection to my PC at home, with netcat.

I still have to find out how to push that data into gpsd programs. I am new in GPS programs.

Also there is this termux command "termux-location", it gives a one-shot current location data, so the device node is accessible (don't know whether I am root or not)."

https://github.com/termux/termux-packages/issues/1330