Intel 05-2409-003 Manual Do Utilizador

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In some applications, when xx_open( ) functions (Global Call, Voice, Fax) are issued 
asynchronously, it may cause slow device-initialization performance. Fortunately, you can avoid 
this particular problem quite simply by reorganizing the way the application opens and then 
configures devices. The recommendation is to do all xx_open( ) functions for all channels before 
proceeding with the next function. For example, you would have one loop through the system 
devices to do all the xx_open( ) functions first, and then start a second loop through the devices to 
configure them, instead of doing one single loop where an xx_open( ) is immediately followed by 
other API functions on the same device. With this method, by the time all xx_open( ) commands 
are completed, the first channel will be initialized, so you won’t experience problems. 

This change is not necessary for all applications, but if you experience poor initialization 
performance, you can gain back speed by using this hint.

For ISDN protocols, the protocol to use is determined at board initialization time and not when 
opening a Global Call device. Protocol parameters are configured in the CONFIG file before the 
firmware is downloaded to the board. If a protocol is specified in the devicename parameter of the 
gc_OpenEx( ) function when opening a device, it is ignored. 

For T1/E1 CAS/R2MF protocols, the protocol to use for a trunk is selected using the “Trunk 
Configurator” feature of the configuration manager (DCM). Protocol files are provided with the 
system software in the \data directory under the Dialogic home directory. A protocol can be 
configured by changing the parameter values in the corresponding Country Dependent Parameter 
(CDP) file located in the \data directory. See the Global Call Country Dependent Parameters 
(CDP) for PDK Protocols Configuration Guide for details on the parameters that can be changed 
for each protocol. If a protocol is specified in the devicename parameter of the gc_OpenEx( ) 
function when opening a device, it is ignored. 

When using Digital Network Interface boards, Global Call supports the handling of multiple call 
objects per channel in a glare condition. An application running on bi-directional circuits is capable 
of handling two CRNs on a single line device, where one call can be in an Idle state, while the other 
call is in Active state. For example, a glare condition occurs when a call has been dropped but not 
released and an inbound call is detected as indicated in Table 10. In order to avoid a long delay in 
processing the inbound call, the Global Call library does not wait for the outbound call to be 
released before notifying the application of the inbound call. 

gc_MakeCall(CRN1) --> 

<-- GCEV_DISCONNECTED(CRN1) 

gc_DropCall(CRN1) -->