Steve Silverwood wrote:

In article ,
pamme says...
I use a USB external modem. When plugged in, the computer automatically
assigned the modem COM3, no special adapters needed. I would think plugging a
TNC in would have a similar affect.

This is assuming you can find a TNC that supports direct connection to
the PC with a USB cable. I have yet to find one. Better to use the
USB-to-serial cables with the appropriate drivers.

look on the Byacom website... One of their members has built just
such
a device although the ax25 stack runs on the host. Much of the low
level
packet work is, however, handled in the modem. Hardware design is very
interesting, it consists of a 8051 derivative processor that has built
in USB hardware and a programmable gate array that implements the modem.
The logic in the gate array is specific to the job at hand (i.e. the
logic that is downloaded into the FPGA for 1200 baud operation differs
from that used to implement 9600 baud).

(try www.baycom.org)

regards
-Willy
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