"Jack Erbes" wrote in message
...
In my general inexperience with things Garmin, I may have some mistaken
impressions about the effect of the Garmin protocol. I thought data in
the Garmin proprietary format would not be read or used by an
application not specifically written to use it. In other words, if an
application was looking for NMEA data strings, it would not read any of
the Garmin proprietary data strings would it?

You are mixing up two things here. Firstly, there is the Garmin protocol.
This is a proprietary *protocol* consisting of binary (non human-readable)
data at 9600 baud.

Secondly, there are proprietary *sentences* or data strings, which are human
readable text, at 4800 baud. These sentences are called proprietary because
they are not defined by the NMEA standard. They have the standard NMEA
sentence format, starting with $P to indicate that they are Proprietary and
ending with a Carriage Return/Linefeed combo like any other NMEA sentence,
but the actual contents is entirely up to the manufacturer of the device.

The difference is for instance that proprietary NMEA sentences will be
passed by NMEA equipment like multiplexers and NMEA-linked instruments, but
a proprietary protocol will not.

Meindert