[aprssig] D700/D710 data port

[Jason KG4WSV]

I can't speak for the 710, but the D700's TNC data in standard format
is unavailable when in APRS mode.  You can put it in verbose mode and
get some data; I suspect what you see is some form of the data going
to the control head, and sufficient work may allow you to extract APRS
data from it.  I was too lazy/insufficiently interested to go farther.

What I plan to do (once I unbrick my T2 proto) is to use the audio
output from the D700 and feed it to the T2, and let the T2 plot on my
Garmin MAP60.  T2 can't transmit, but there ya go.

With the D700, sufficient hacking to decode the protocol between the
radio and the control head may allow something clever like inserting
the T2 between the control head and mike and the radio, and do
something clever there to allow using the D700 APRS app and the T2 at
the same time.

If you keep on with that FMI interface, I'll take the D700 in the
house and put an Alinco with a T2-135 and a nuvi in the truck. (:

-Jason
kg4wsv