PPL timer and configuration bytes are stored on a per D channel basis for ISDN configuration. If a timer or configuration byte is changed for a D channel, all B channels controlled by the D channel will use the new timer or configuration byte value.
If you change the type of ISDN connection using the ISDN Interface Configure message, the system resets all B channel configuration parameters back to their default values. If you have to modify the default ISDN PPL configuration bytes or PPL timers, you must use the PPL Configure message after you change the Connection Type.
The following API messages are used to send and receive call processing PPL events:
• PPL Event Request
This message is initiated by the host, sends an external
event directly to the specified PPL component.
The message can include the PPL component, PPL event, ICB
count, ICB type, ICB subtype, and data.
ICB subtype values can include:
• PPL general purpose register data
• ISDN formatted IE
• ISDN raw IE
• PPL Event Indication
This message enables the PPL component of the CSP to report an external event directly to the host application.The message can include the PPL component, PPL event, ICB count, ICB type, ICB subtype, and data.
ICB subtype values can include:
• PPL general purpose register data
• ISDN formatted IE
• ISDN raw IE
• PPL argument 2 data