[aprssig] APRS data via perl-to-tnc

Lee Bengston lee.bengston at gmail.com
Sat Nov 26 13:22:34 CST 2011

On Thu, Nov 24, 2011 at 1:14 PM, Lynn W. Deffenbaugh (Mr)
<ldeffenb at homeside.to> wrote:
> Perl may be enabling flow control on the port that your cable or Perl isn't
> providing.  Try tying RTS to CTS and DTR to DSR and CD on the computer AND
> TNC end of the cable.  I've had devices before that would not send out their
> data until they had their handshaking provided and software that wasn't
> asserting DTR and/or RTS.  Once I joyplugged (typically the device end of,
> but sometimes both ends of) the cable, communication magically flowed.  And
> yes, it would work with some software and not with others based on which
> signals the software was instructing the PC to provide.

Thanks everyone for the responses.  I knew ultimately the solution to
the problem was going to be simple and make me want to kick myself.
When "\n" didn't work by itself for the line terminator, I evidently
kept trying "\r\n" instead of "\r" by itself.  It appears that the
Kantronics box doesn't like an extra "\n" in there.  So the
Device::SerialPort perl module works fine, and the result is a very
useful script.

The problem solved by the script - even though the manual for the
9612+ says that the unit will stay in KISS mode after a power cycle,
it really doesn't.  It resets and ultimatley ends up at the "enter *
to set the baud rate" prompt.  I haven't incorporated the script into
the boot cycle of the computer yet, but the idea is that if the PC
reboots, it doesn't know what mode the TNC might be in.  So the script
is able to figure it out and get it into KISS mode either if it has
been reset due to a power cycle or if it happens to be in terminal
mode for some reason.  If it is already in KISS mode, the script
harmlessly takes it out of KISS, finds the cmd prompt and sets it back
to KISS.

Lee - K5DAT

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