Actually, the two port limit is arbitrary. I could double that in about a day,
including testing. Better still, you can run multiple instances of my program
to capture as many ports as you like and use the networking capability to merge
the datastreams.

I feel that the major functionality in my program is the NMEA data logging and
display. The networking functions may prove useful for large yachts wanting
data displays at multiple locations or on wireless devices. The multiplexing
code was needed to implement the networking so that each instance of the program
could display data from other instances on the network as well as data captured
from local NMEA devices. Adding an extra serial port to the multiplexor stack
was trivial, and removed the dependency on external hardware.

However, just because I don't actually require external hardware doesn't mean
that I don't recommend it. Using an opto-isolated NMEA (RS-422) to serial
(RS-232) converter is a very good idea, for several reasons. I doubt
multiplexors are any more expensive, if the alternative involves buying extra
serial ports and converters.

Though I don't have hands-on experience, the research I did while planning my
own NMEA network left me convinced that the ShipModul products are very cool.


Glen Wilson
See my NMEA instrument repeater, logging, and networking program at:
http://216.76.94.234/3NMEA.shtml



On Mon, 4 Aug 2003 23:55:12 +0200, "Ger"
tempted fate with:


"Larry" schreef in bericht
.. .
Too bad it won't buffer several input ports so we can use it as a
multiplexer.

Larry, this functionality is beyond the purpose of the program.

Actually it would not be a big deal to realize, but how many serial ports
does a "normal" PC have? My desktop has 2 serial ports, my laptop one, and
many newer laptops dont even have a serial port these days, but only a USB
port for serial I/O.

Glen Wilson (see further this thread) has witten a very useful program, but
his program is also limited to two serial ports for multiplexing NMEA data.

In my opinion the best solution when you need several NMEA inputs is to use
a NMEA multiplexer like this one: www.shipmodul.com.

Glen "Wiley" Wilson usenet1 at worldwidewiley dot com