LUSYN
Asterisk history buffer patches (1.2)
Overview
On BT lines in the UK, caller ID information is sent before the first ring. The start of the Caller ID feed is signalled by a polarity reversal. The X100P card does not support detection of polarity reversals, so Tony Hoyle devised a method of using a buffer to store data as it is received. Once the first ring arrives, the buffer has a history of what was received immediately before so the caller ID information can be extracted.
Although originally written for the UK, this patch has been known to work in other countries.
These patches are provided under the GNU General Public License (GPL) as is and with no warranty.
Bug report
http://bugs.digium.com/view.php?id=1719
Obtaining the patches
The easiest way is to use wget when appyling the patches, as illustrated below. Download links are :
Prerequisites
If you are using a production version of v1.2.x, you may be affected by a bug in ring handling. You will also need to apply asterisk_ringbegin.diff.
Applying the patches
First of all you need to obtain the source code. You can follow the instructions here. Then, as root, do the following :
cd /usr/src/zaptel
wget http://www.lusyn.com/asterisk/zaptel_usehist.diff
patch <zaptel_usehist.diff
make clean
make install
make config
cd ../asterisk
wget http://www.lusyn.com/asterisk/asterisk_usehist.diff
patch -p0 <asterisk_usehist.diff
You may require this patch for v1.2+ if caller ID and distinctive ring are not working :
wget http://www.lusyn.com/asterisk/asterisk_ringbegin.diff
patch -p0 <asterisk_ringbegin.diff
Now compile and install Asterisk :
make clean
make install
Edit /etc/asterisk/zapata.conf and use the following three lines for CallerID :
usecallerid=yes
cidsignalling=v23
cidstart=usehist