At 22:15 19 July 2008, Doug Hoffman wrote:
Peter Wyld wrote:

Shouldn't you be looking for the NMEA datastream on the 6way
'telephone' socket, not the DB9 serial port?

If you have the GPS20 connected to the LNAV via this port, you can
take
a
tap from it to run the PDA.

I called Cambridge tech support in July 2007. Talked with someone named

Gary. He said emphatically that I should *not* use the 6-way Datacom
port and that I should use the DB9 for a PDA. He also gave me the DB9
pin#s that I should use. It did not work. However, the DB9 works just
fine for uploading/downloading files from my PC to/from the GPSNav-20.

Regards,

-Doug

The DB9 port is the correct port for a PDA as it can provide File
communications and also output full NMEA data, but only if requested by
the PDA.
To output NMEA the PDA has to first send the initialisation command word
"NMEA" to the DB9 port. Therefore the PDA software has to have been
written to specifically support the GPSNAV and have a GPSNAV connection
mode.
In for example Seeyou Mobile when you set the Hardware setting to GPSNAV,
Seeyou Mobile sends this command to the GPSNAV at startup and the NMEA
stream commences.
Almost certainly the reason you could not get your PDA Software working on
the DB9 port was either;
1)The PDA software does not specifically support the GPSNAV, and does not
send the NMEA command word at startup.
2) You have not set the software to be configured for a GPSNAV.
3) You connect/start up your Cambridge and PDA in an order that does not
allow the GPSNAV to receive the NMEA initialisation command. Eg Start the
PDA program first then power on the GPSNAV or start the PDA software then
plug it into the cradle.

Hope this helps
Ian