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No, I believe this IS that important. Can you guide me through your
interpretation of the Reply-Ack specification from
<a class="moz-txt-link-freetext" href="http://www.aprs.org/aprs11/replyacks.txt">http://www.aprs.org/aprs11/replyacks.txt</a> and tell me where you
believe that it says that a trailing }06 on your AA: example should
be interpreted as a ReplyAck? As I read that spec, {MM}AA is a
reply ack, {MM} is an ack that implies that the ack-issuer is
Reply-Ack capable, but }AA is just another bit of message text and
part of the AA: that should display "AA:I'm not here }06" to the
recipient.<br>
<br>
The } is only a Reply-Ack delimiter when contained within a {seq as
far as I can see in the spec.<br>
<br>
What did I miss here?<br>
<br>
Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32<br>
<br>
PS. Sections of the spec that I find particularly relevant:<br>
<br>
(Nothing about }AA being anything in particular)<br>
<blockquote type="cite">
<pre>Original APRS ACK: {##### <== There were no restrictions on #####
New 1999 REPLY ACK: {MM}AA <== This embedds ACK in next outgoing msg</pre>
</blockquote>
<br>
(Nothing about standalone }AA, just "embedded")<br>
<blockquote type="cite">
<pre>COMPATIBILITY: 100% backwards compatible with all code. The REPLY ACKS
are embedded in the 5 digit line number. Old code doesn't care.
</pre>
</blockquote>
<br>
(Nothing about "if no ack is needed back, then }AA is used")<br>
<blockquote type="cite">
<pre>The format for the line number for outgoing message numbers is
"{MM}AA" where MM is the outgoing message number and AA is the "free ACK"
if needed. If no ACK is pending, then the message # is "{MM}". </pre>
</blockquote>
<br>
(Only append AA, not }AA)<br>
<blockquote type="cite">
<pre>1) ... But AA is only appended at the INSTANT of transmission.</pre>
</blockquote>
<br>
(Only look for AA in the ack/seq, not }AA in every message)<br>
<blockquote type="cite">
<pre>2) RECEIVE messages and look for AA. IF AA matches the MM of one of your
outgoing messages, then consider that message ACKED.</pre>
</blockquote>
<br>
(Buffer with {MM}, not just buffer with } if no ack is needed, the
AA gets added before transmission, but ONLY if you're buffering an
{MM} and requesting a corresponding ack)<br>
<blockquote type="cite">
<pre>6) Note, that in #1, above, that when the user prepares each message line,
that it is buffered up with only the {MM} line number on the end.
The AA (if pending) is not attached until the instant that packet is
transmitted.</pre>
</blockquote>
<br>
So, where did I miss the spec that would have said something like:<br>
(THIS IS NOT IN THE SPEC!)<br>
Queue non-ack-requesting messages with a trailing } and append any
pending AA at the instant that packet is transmitted.<br>
(THIS IS NOT IN THE SPEC!)<br>
<br>
Oh, and it would probably have also described:<br>
(THIS IS NOT IN THE SPEC!)<br>
A message with just a trailing } indicates that the message sender
is not requesting an ack for this message, but is indicating that it
is Reply-Ack capable.<br>
(THIS IS NOT IN THE SPEC!)<br>
<br>
Nope, I'm just not seeing either of the above nor anything that
describes }AA.<br>
<br>
<br>
On 11/5/2011 9:49 AM, Brent Hildebrand wrote:
<blockquote
cite="mid:CAMZt4pqYXeFgw65010W1jqoXGBTD26EZibEmRTuuO-FqV54Uvw@mail.gmail.com"
type="cite">Line numbers are of the form {xx. Reply/Acks }yy. A
Reply/Ack is not a linenumber and should not be interpreted as
such. Thus, an exchange with one user having AA turned on might
look like this:<br>
<br>
WB1XYZ>APRS::KK2ABC :Hello there! {06<br>
KK2ABC>APRS::WB1XYZ :ack06<br>
KK2ABC>APRS::WB1XYZ :AA:I'm not here }06<br>
<br>
There is no line number in the AA message, only a Reply/Ack. If
KK2ABC returns to their keyboard and send a reply, the exchange
might like like this:<br>
<br>
KK2ABC>APRS::WB1XYZ :I'm back! {02}06<br>
WB1XYZ>APRS::KK2ABC :ack02}06<br>
WB1XYZ>APRS::KK2ABC :Good to hear from you {07}02<br>
KK2ABC>APRS::WB1XYZ :ack07}02<br>
WB1XYZ>APRS::KK2ABC :Where have you been? {08}02<br>
// KK2ABC leaves again and turns on the AA message...<br>
KK2ABC>APRS::WB1XYZ :AA:I'm not here }08<br>
<br>
The point is, that a reply/ack can be added to a AA message and it
should not be interpreted as a message number because it is not of
the form of a message number.<br>
<br>
Old client programs, the message number was of the form {xxxxx.
When reply/acks were added to newer programs, they did not break
anything. Generating the real "ack" as :ack02}06 is only ack'ing
message number 2. On programs that understand reply/acks, ;ack02
would have been sufficient. For backward compatibility, the ack
included the reply/ack. Putting the reply/ack in the AA does not
cause backward compatibility issues because the reply/ack is not
in message number format and should not generate a return ack. <br>
<br>
OK - I'll disappear again. This is probably not that important.
BH KH2Z<br>
<br>
<br>
<div class="gmail_quote">On Sat, Nov 5, 2011 at 5:00 AM, <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:aprssig-request@tapr.org">aprssig-request@tapr.org</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div text="#000000" bgcolor="#FFFFFF">Bob's 2) precludes
that. The "ack" request }nn is the same thing as a "Line
number" which Bob says that AA's should NOT have.<br>
<br>
Unless you're referring to an APRS client implementation
that actually issues such ack requests on it's AA (without
the colon) packets? You didn't give us much context here.
<br>
</div>
</blockquote>
</div>
<br>
<br>
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</blockquote>
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