Editing Terminal node controller (section)

== Terminal data port ==


TNCs were originally designed to accept messages from a human typing on a [[dumb terminal]]. TNCs had a DB-25 or DE-9 connector carrying [[asynchronous start-stop]] bytes with [[RS-232]] signal levels.  This could also be used with the [[serial port]] of a personal computer.  Serial ports are now pretty much extinct, but USB-to-serial converter cables are available.

However, typically a human uses a more sophisticated software package running on a personal computer that sends messages to the TNC using the [[KISS (TNC)]] protocol or the 6PACK protocol.<ref>
{{cite web
|author-last=Welwarsky
|author-first=Matthias
|translator-last=Sailer
|translator-first=Tom
|url=http://private.freepage.de/cgi-bin/feets/freepage_ext/41030x030A/rewrite/alexs/xfr/flexnet/6pack_en/6pack.htm
|title=6PACK a "real time" PC to TNC protocol
|access-date=2013-05-19}}
</ref>

Modern Software TNCs provide [[Internet protocol suite|TCP/IP]] interfaces that can be accessed across computer networks.  For example, it is possible to run a software TNC on a [[Raspberry Pi]] near the radio and access it from a laptop computer in another location.  Software TNCs also provide "[[Pseudoterminal|pseudo terminals]]" so they can be used with old applications that only know how to use serial ports.

<br />