Hardware Echo-cancellation¶
It is recommended to use telephony cards with an hardware echo-canceller module.
Warning
with TE13x, TE23x and TE43x cards, you MUST install the echo-canceller firmware. Otherwise the card won’t work properly.
Know which firmware you need¶
If you have an hardware echo-canceller module you have to install its firmware.
You first need to know which firmware you have to install. The simplest way is to restart dahdi and then to lookup in the dmesg which firmware does DAHDI request at startup:
wazo-service restart
dmesg |grep firmware
[5461540.738209] wct4xxp 0000:01:0e.0: firmware: agent aborted loading dahdi-fw-oct6114-064.bin (not found?)
[5461540.738310] wct4xxp 0000:01:0e.0: VPM450: firmware dahdi-fw-oct6114-064.bin not available from userspace
In the example above you can see that the module wct4xxp
requested the dahdi-fw-oct6114-064.bin
firmware file but did not found it.
But you now know that you need the dahdi-fw-oct6114-064.bin
firmware.
Install the firmware¶
When you know which firmware you need you can install it with xivo-fetchfw
utility.
Use
xivo-fetchfw
to find the name of the package. You can search fordigium
occurrences in the available packages:xivo-fetchfw search digium
Find the package name which matches the firmware file you need. In our example, we need the
dahdi-fw-oct6114-064.bin
file which is supplied by the package nameddigium-oct6114-064
:xivo-fetchfw install digium-oct6114-064
Activate the Hardware Echo-cancellation¶
Now that you installed hardware echo-canceller firmware you must activate it
in /etc/asterisk/chan_dahdi.conf
file:
echocancel = 1
Next step¶
Now that you have loaded the correct module for your card you must:
- check if you need to follow one of the Specific configuration sections below,
- and continue with the next configuration step which is to configure your card according to the operator links.
Specific configuration¶
This section describes some specific configuration. You should not follow them unless you have a specific need.
Use the Hardware Echo-canceller for DTMF detection¶
If you have an hardware echo-canceller you may want to use it to detect the DTMF signal (instead of asterisk).
Create the file
/etc/modprobe.d/xivo-hwec-dtmf.conf
:touch /etc/modprobe.d/xivo-hwec-dtmf.conf
Fill it with the following lines replacing
DAHDI_MODULE_NAME
by the correct module name (wcte13xp
,wct4xxp
…):options DAHDI_MODULE_NAME vpmdtmfsupport=1
Then, restart the services:
wazo-service restart