[FADCA] More radios with less ports

[Chuck Hast]

Folks,
One of the things I have been running back and forth in my mind is how to
get more ports without adding cards. One solution which the guys out in
TX were using was multidrop KISS, this is KISS that along with the CRC uses
a two byte address to talk to the TNC's over a single serial port. If you run
the serial port fast this could be a way around the issue of how to get more
radios on a computer without adding computer hardware.

I do recall having made it work back years ago when we first started working
with FPAC. But never continued on with it. I think the original notes are on a
old OS/2 machine which has been put away for posterity. I will see if I can
get it on line and dig up the data. In truth I think that the CRC mode
we presently
use just assumes that the KISS TNC has a address of 00 or 01 (which is what
the default EPROM image has) and takes it from there. But if you look at the
FPAC configuration files there is a third mode beyond CRC KISS and that is for
multi-drop and it allows you to give the addresses of the devices on the
serial port.

Of course if we can get USB drivers for DOS, and indeed yes they are out
there, we could use a multi-port USB hub and just hang serial port converters
on the hub.

Now if I can only get Linda to add USB to the TNC's.

-- 
Chuck Hast 
To paraphrase my flight instructor;
"the only dumb question is the one you DID NOT ask resulting in my going
out and having to identify your bits and pieces in the midst of torn
and twisted metal."