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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>My zaptel.conf is like this:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>span=1,0,0,esf,b8zs<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>bchan=1-24<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>span=2,0,0,esf,b8zs<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>bchan=25-48<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Is there something better to use?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>If I read this right that should turn off
the robbed bit signaling. I believe this matches the opposite equipment. You
are correct, in D4 the 6<sup>th</sup> and 12<sup>th</sup> frames rob for the A
and B bit, in ESF the 6<sup>th</sup>, 12<sup>th</sup>, 18<sup>th</sup>, and 24<sup>th</sup>
rob for the A, B, C, and D bits.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I have been working further since my previous
message. Another clue might be this: The message I send is 10 bytes long, the
response is 10 bytes and then some additional data of 10-20 bytes for each
message. Exactly every eighth time I send the my message, the reply message
comes back correctly. I have a sniffer that says the opposite end is sending
the correct string everytime. I am running this as a little command prompt
program at the moment and each time I run it, it sends the message once, so
there is no particular timing involved. Also, if I loop back from port 1 of
the Digium 405 card to port 2 of it with a crossover cable, I get perfect TX/RX
between the same app running in two different windows. One app operates on
chan 1 the other on chan 25.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Thanks all,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Doug<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<div>
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face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabindex=-1>
</span></font></div>
<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> Wai Wu
[mailto:wkwu@calltrol.com] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, October 03, 2007
9:24 PM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">dehlers@css-design.us</st1:PersonName>;
Asterisk Developers Mailing List<br>
<b><span style='font-weight:bold'>Subject:</span></b> RE: [asterisk-dev] Zaptel
Programming</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=blue face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:blue'>Did you configure the span as PRI or
RobBit? If your span is PRI, is your channel 0 the D-Channel? If RobBit,
(anyone correct me it I am wrong) the zaptel driver inserts controlling bits
into the data frames. If I am not mistaken, the 6th and 12th frame. That means,
you might have a hard time send and receiving pure data across those channels.</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabIndex=-1>
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<p class=MsoNormal style='margin-bottom:12.0pt'><b><font size=2 face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
asterisk-dev-bounces@lists.digium.com
[mailto:asterisk-dev-bounces@lists.digium.com] <b><span style='font-weight:
bold'>On Behalf Of </span></b>Doug Ehlers<br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, October 03, 2007
8:26 PM<br>
<b><span style='font-weight:bold'>To:</span></b> asterisk-dev@lists.digium.com<br>
<b><span style='font-weight:bold'>Subject:</span></b> [asterisk-dev] Zaptel
Programming</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello all,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I hope this is the right place to post this message, I
didn’t see just a list for Zaptel programming.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am working on a project using a Digium 405 T1 card.
I am trying to write an application to talk via the T1 interface to another piece
of equipment.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Very simply, I have set the line configs in zaptel.conf and
then run ztcfg to activate them.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>In my C++ program, I open the data channel ->
fd=open(“/dev/zap/1”,O_RDWR). This application is very similar to a PRI
line in that one DS0 functions as a control channel with a pseudo HDLC
communications type link and the other 23 channels get dynamically assigned
usage based on incoming and outgoing calls. Each DS0 is setup to be CLEAR
mode, no signaling.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>After opening the device, I check the buffers and change
them to some smaller sizes, make them act immediate, etc.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am able to write my message and see the opposite system
get it and acknowledge it with a message back -> write(fd, buffer, length)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The problem is in getting the data back. I have just a
simple read loop setup to read the data from the buffers that I believe were
setup after the device was opened. This is being done with a simple
read(fd, buffer, length) kind of command. I assume with enough buffers, I
should be able to read the data rapidly enough to not lose anything. I
always get something back buy 1 in 5 times its actually correct (when no
traffic is present, the opposite side is sending 0xFF always so its pretty easy
to know when there is data coming). Most of the time the received data
bares a resemblance to the message that was sent, but certainly isn’t it.
Occasionally the reply message is exactly correct and all is well. Its
almost like the bit alignment is off or something.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Is there something I should be doing differently to reliably
read data back from a channel like this? My next step will be to deal
with the audio channels and the mechanism will be similar. I have looked
at a number of example applications such as fxotune.c and spent some time in
chan_zap.c trying to discern the correct way to read data, but haven’t yet
turned anything up. There are quite a few options to the zaptel API and I
haven’t yet located a good document explaining how to work with it at the level
I need.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Can anybody give me some pointers or point me toward other
information and resources?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Many thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Doug<o:p></o:p></span></font></p>
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