5.3. gc_Open( ) and gc_OpenEx( ) Restrictions

In R4 applications that use DM3 flexible routing configurations, it is possible to specify a network device, protocol, and voice device in an ASCII string pointed to by the devicename parameter in gc_OpenEx( ) and gc_Open( ) commands.

An example of the devicename parameter is as follows:

    :N_dtiB1T1:P_ISDN:V_dxxxB1C1

where:

• N_ denotes a network timeslot device, in this example, dtiB1T1
• P_ denotes a protocol, in this example, an ISDN protocol
• V_ denotes a voice channel device, in this example, dxxxB1C1

The following restrictions apply:

• The network timeslot device field (N_) is required.
• The protocol identifier field (P_) is not used since, for DM3 boards, the protocol is determined at board initialization time and not when a GlobalCall device is opened. However, to provide compatibility with R4 on earlier-generation boards, the protocol identifier can be specified.
• The voice channel device field (V_) is optional with the following consequences:
  • Attachment to different types of DM3 voice devices is dependent on the protocol downloaded. For example, if one board has ISDN for protocols and another has T1 CAS, the T1 CAS network devices cannot be attached to the voice devices on the ISDN board. For more information on limitations, see section 2.3.5. Determining Channel Capabilities in Flexible Routing Configurations.
  • If the voice channel device is specified, it is automatically associated with the specified network device (it is attached and routed).
  • If the voice channel device is not specified, the application may include function calls, typically, dx_open( ), gc_Attach( ), gc_GetNetworkH( ), and nr_scroute( )* to manually associate the voice channel device with the network device. This option may be desirable when porting an existing ISDN application that uses earlier-generation boards to an application that uses DM3 boards.

*Note: Routing can also be accomplished using gc_Listen( ) and gc_GetXmitSlot( ).
 
See Section 11.3.1. Initializing the GlobalCall API for DM3 Boards Only (Flexible Routing) for examples.

Click here to contact Dialogic Customer Engineering