gps on banglejs2: report satellites before the fix

[pavelmachek]

Affected hardware version

Bangle 2

Your firmware version

2v19

The bug

GPS fix (as reported by Bangle.on('GPS', function(fix) { ... });) contains satellites field. Unfortunately it is only nonzero when we actually have a fix.

To provide some kind of feedback before fix is acquired, it would be nice to know number of satellites decoded even before we have the fix. (Currently such information is only available with gps-raw interface). There's big difference between "no fix, 6 sats decoded" -- which means "stay in place and wait a minute" and "no fix, 0 sats" which means "move under clear sky, can't get a fix here".

My proposal would be to report fix.satellites as number of satellites with known snr ratio when we don't have a fix, but other solutions are possible.

Installed apps

No response

[bobrippling]

Sounds like a nice idea, I expect it would be a firmware change although it looks like satellites is unconditionally set.

but perhaps we'd want to change code around here, which queues callbacks for the GPS events.