[aprssig] Error checking within APRS packets

Lynn W. Deffenbaugh (Mr) ldeffenb at homeside.to
Thu Jun 23 17:26:22 EDT 2011

On 6/22/2011 12:43 PM, Bill V WA7NWP wrote:
> The APRS spec says to never use a tilde in the text field?   If it's
> true, that's silly.   It's just another ASCI character.  The
> bit-stuffing magic happens at the hardware packet level and is totally
> independent of what we put in the packet data -- for APRS or any other
> packet application.

The issue isn't with AX.25, but I believe there are some TNCs out there 
that use the tilde character as a way to switch sessions or streams or 
something.  Given that, if the tilde character appears anywhere in a 
packet that needed to be transmitted by that TNC, most likely in some 
sort of CONVerse mode, not KISS, then really bad things would happen.

Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32

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