[time] garmin gps25-hvs questions - initial results

[dave morgan]

On Sat, 04 Dec 2004 16:00:10 +0000, dave morgan <morgad at eclipse.co.uk>
wrote:

>
>I thought I would try to get my GPS rx working this weekend - that is
>working in the sense of proving it can pick up some signal, and talk
>to the computer, rather than optimizing the antenna position or
>worrying about calibrating for cable delays, etc. It is a Garmin
>GPS25-HVS model (6-40 volt, rs232 output).
>
>A couple of questions -
>
>1) how do I set the baud rate to 4800 on /dev/gps1? or /dev/ttyS1
>(machine is Debian Linux) Or do I not need to, is it done
>automatically by the ntp refclock driver?

The GPS turns out to be running at 9600baud and only outputting PGRME 
and PGRMF sentences :-( *NOTHING* I do results in any data being sent
successfully back to the GPS. I have tried different terminal 
emulators, and also echo -n "blah\n\l" >/dev/ttyS1, but no luck.
If I have read the manual correctly, the GPS will echo back any 
commands it accepts, I have never got a byte back that I sent.
So I am unable to change output format, or baud rate ...

>
>2) Do I have to do anything special to the PPS output line in terms of
>buffering, or do I just connect to the DCD pin? or some other pin?

This turns out to work ok as-is :-) the CD icon on the terminal 
emulator flashes once per second (with a 12v psu).

If all else fails I might try to use it as a PPS source :-/

best regards
Dave Morgan
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