System information

Dialogic
®
HMP Software Release 3.0WIN Release Guide — December 2010 33
Dialogic Corporation
Features
Whenever transaction recording from an HMP soft Bus TDM time slot, i.e., from an HMP
media or IP device, is required, use an HMP voice device instead. In this case, there is no
limitation and both time slots are supported. The following table summarizes:
Echo Cancellation
Several parameter updates are recommended when using the Dialogic
®
Springware
boards in gateway mode (bridging to and from IP devices) to reduce echo that may be
originated in the board’s analog interfaces.
First, echo cancellation should be enabled on the HMP IP devices globally and statically
by updating the HMP .config file as shown below. Refer to the Dialogic
®
IP Media Library
API Programming Guide and Library Reference for more information.
[IPVSC]
SetParm=0x1b12, 1 !Enable EC on HMP.
SetParm=0x1b13, 512 !Set EC tail length to 128(16ms), 512(64ms)
Once echo cancellation is enabled, the system has to be reconfigured. Follow the steps
below:
1. Run the following command to generate the .fcd file:
fcdgen <license filename>.config –o <license filename>.fcd
2. Re-initialized the HMP system using DCM as explained in the product
Configuration Guide.
3. Once complete, the application needs to control echo cancellation on the IP
devices at run time. This is accomplished using the ipm_SetParm( ) function on
an IP media channel basis as shown in the code excerpt below. In this case, echo
cancellation is enabled using the corresponding device handle (nDeviceHandle)
of an IP media channel bridged in full-duplex with an analog device in gateway
mode.
ipm_SetParm(nDeviceHandle, PARMCH_ECACTIVE,1) //Enables EC
for this channel
ipm_SetParm(nDeviceHandle, PARMCH_ECNLP_ACTIVE,1) // Enables
Non-Linear processing for this channel
It is also recommended that the application reduce the volume of receive audio
through the IP device. This can be accomplished at run-time, on an IP media
Voice Device
Handle Technology
TDM Time Slot One
sc_tsarrayp[0]
TDM Time Slot One
sc_tsarrayp[1]
Result
HMP HMP soft Bus CT Bus Supported
CT Bus HMP soft Bus Supported
CT Bus CT Bus Supported
HMP soft Bus HMP soft Bus Supported
D/80PCIE-LS HMP soft Bus CT Bus Not Supported
CT Bus HMP soft Bus Not Supported
CT Bus CT Bus Supported
HMP soft Bus HMP soft Bus Not Supported