On a sunny day (26 Jul 2018 21:03:17 GMT) it happened ray carter
 wrote in :

>Having discovered that there are GPS 'dongles' that plug into the USB
>port - readily available for $10-ish, I decided to pick up my old A+ and
>do the thing. I have a 5" hdmi touchscreen on it for display, so no kbd
>or mouse needed.You can actually just capture the GPS output from one of
>the tty ports, but I wanted more than that so installed gpsd and
>foxtrotgps and we're good to go. With that in place and lxde running,
>about 2/3 of memory is used, so I'll go with twm - that more than cuts
>memory usage in half. Plan is to move it over to a zero. I have a fairly
>good capacity power bank to use it with.

Nice.
Only restriction on using /dev/ttyUSB* is that if you plug in / out
serial devices the kernel can renumber things.

Raspi has a real serial port on /dev/ttyAMA0 accessible via 2 GPIO pins.
Many GPS modules come with logic level serial out.
This stuff I wrote uses /dev/ttyAMA0
 http://panteltje.com/panteltje/xgpspc/index.html
website needs updating...
root@raspberrypi:~/compile/pantel/xgpspc# uptime
 11:51:02 up 72 days,  4:19, 10 users,  load average: 1.34, 1.52, 1.52

Stable :-)

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