Flag Frames

[fsanford@foxboro.com (Fred Sanford)]

Hello All,

I saw a reference in the PacComm NB-96 modem manual, that all TNCs may not
generate flag frames at the beginning of a transmission.  I working on
some regeneration logic for a 1200 baud (yes I know that its old stuff but
people are cheap in my part of the country and don't want to spend money
for equipment that can do 9600 baud) realtime packet repeater.  I had
built a prototype of the regen logic that included a flag frame detection
circuit to start the retransmission of a receive signal, but found that
some TNCs would not trigger the flag frame detection circuitry.  After
reading the statement in the NB-96 modem manual, I beginning to wonder if
all tncs really generate flag frames.  The tncs that I seen to be having
problems with are TNC-1s and a KPC-2 (or maybe that is a 3).

Does anyone out there know if the statement in the NB-96 modem manual is
correct about not all tncs sending flag frames is true ???

73 & Happy New Year,

Fred - ka1cqd