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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Greetings!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>As I read through the specs I have a couple of mysteries.<o:p></o:p></p><p class=MsoNormal><a href="https://www.tapr.org/pdf/AX25.2.2.pdf">https://www.tapr.org/pdf/AX25.2.2.pdf</a><o:p></o:p></p><p class=MsoNormal><a href="http://www.ax25.net/kiss.aspx">http://www.ax25.net/kiss.aspx</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The first byte is ‘C0’.<o:p></o:p></p><p class=MsoNormal>The second byte-high nibble is a port byte - useful if talking to a multi-port device I presume.<o:p></o:p></p><p class=MsoNormal>The second byte-low nibble is to flag to define the rest of the frame. Should be 00 unless actually controlling the TNC in some fashion.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The last byte of the Destination Address Subfield, A7, is CRRSSID0. The C is the mystery. If A1-A6 contains a TOCALL, should C be a ‘1’ or ‘0’. My first inclination is to believe it should be a ‘0’ (Response V.2.X) if the packet is not a TNC command. But then, a ‘1’ could be signaling a command for a distant TNC. Or does it really matter the packet is being applied to APRS?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Regarding bit (un)stuffing, this appears to not apply to the KISS packet but is an action taken at the point of transmission/reception.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Please comment.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best regards,<o:p></o:p></p><p class=MsoNormal>Fred N7FMH<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p></div><div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br />
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