Re: [gpsd-dev] AIS NMEA TAG Blocks

[Ed W]

On 27/08/2014 10:13, Eric S. Raymond wrote:

Iván Sánchez Ortega <address@hidden>:

I, for one, would like to see the secs/msecs problem solved before GPSD 
embarks on the enterprise of writing TAGblocks.

Sound advice.  I've added it to the TODO entry.

Any chance the TODO could be updated with my reply? (quoted below for ease)

I do think this feature would be very helpful to say have multiple GPSs and failover to just one at a time as they are available

Thanks

Ed W

It might be too obvious, but observations of data suggest that you just count the number of digits?

- 10 digits = seconds
- 13 digits = millisecs

Note that I'm suggesting that we *add* these, not *consume* them from an upstream.  As such you are free to make your own definition.

My request would be 13 digit millisecs.  My requirement is to be
a) able to play the stream back with moderate precision at some later time.
b) Filter multiple GPS units from the resulting mux'ed output NMEA stream

The use of a TAG block would work perfectly for my requirements... As long as we document what format WE use, I don't see a problem.

I found this interesting
    http://www.nmea.org/Assets/may%2009%20rtcm%200183_v400.pdf

Kind regards

Ed W