Re: [gpsd-users] Galileo

[Gary E. Miller]

Yo aimdev!

On Thu, 8 Mar 2018 11:36:31 +0000
aimdev <address@hidden> wrote:

> Looking at the u-blox 8 / u-blox M8 Receiver Description in binary
> mode the UBX svid for gallileo is 211-246.

Yup.

> There appears to be two means to resolve the Galileo (or any other
> GNSS), either by determining the constellation by the type of nmea
> message, or utilising the vendor specific binary.

More than two.

> I believe that from your comments that this may not have been
> implemented for the u-blox m8, please can you confirm this.

Yup, not yet.  Gonna take some changes to the current data structures
for the extra info.  Thus an API change, and all the tools will have to
change to understand the new structure.

> I can try to add the functionality into the code, however I would
> say  C is not my strongest language. I appreciate due to the varying
> vendor binary formats this is a bit of a task.

The coding will not be too bad, just a lot of it all over.

> I look forward to your reply and any hints

The satellite index, PRN, ID, etc., is used a lot of places in
different contexts: RTCM, Almanac, skyview, raw data, etc.

Start in gpsd.h and gps.h.  In gpsd.h the PRN is stored in two GPS
specific structs for Oncore and Zodia, that can prolly be left for now.

In gps.h, the sat ID is all over: struct rangesage_t, struct consat,
struct almanac_t, and a bunch of other places...

Some places, like the almanac can be left alone as they are GPS
specific.  Other places, like struct satellite_t will need the addition
of a variable for constellation index. 

The that new variable needs to be filled in by the ubx driver, passed
out the JSON (gpsd_json.c), read in by the clients (libgps_json.c),
the displayed by the clients (cgps, xgps, etc.)

Gonna be a big job, I've been hesitant to rip open that scab.  If you
want to get started then lets do it.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        address@hidden  Tel:+1 541 382 8588

            Veritas liberabit vos. -- Quid est veritas?
    "If you can’t measure it, you can’t improve it." - Lord Kelvin

pgpqGVK0Lbeub.pgp
Description: OpenPGP digital signature