Request_Instruction is issued for calls arriving at the VRU that are already under ICM script control. The successful running of this function causes data received to run a VRU based script.
Request_Instruction should be issued only once during a call. If it is issued, then the New_Call should NOT be issued.
If this request is successful, the ICM provides instructions in a reasonable amount of time. If the Instructions are not provided, a Dialogue_Failure_Event_Send is sent with a status code of E_TIMEOUT.
The DialedNumber is required. If the DialedNumber is not provided, the ICM fails the request. This causes a signal to the state table to issue a Dialogue_Failure_Event_Recv and the returned status code E_INVALID_MESSAGE.
If the ICM cannot provide instructions because a script is not active for the given call type, the state table is signaled to issue a Dialogue_Failure_Event_Recv and the returned status code E_NO_SCRIPT.
In all other fatal error conditions the state table is signaled to issue a Dialogue_Failure_Event_Recv and the returned status code E_UNSPECIFIED_FAILURE.
When using SV177 as the TrunkGroupID the value of SV177 should be assigned to a numeric variable using the Assign Data state table action. This variable should then be used as the value that is sent as TrunkGroupID.