
The script and call progression
This section describes how the system processes a call using a TSM script.
- The system accepts a call from the central office or switch on a telephony card.
 - The telephony card then signals the T1 interface process (TWIP), that it has accepted the call.
 - TWIP signals the AD process that it has accepted the call.
 - AD checks a service table to determine the service and process required for the call. In this example, TSM is the selected process.
 - TSM reads the script instructions and allows the script to control the sequence of events during a call.
 - AD takes control when the call has ended.
 
The following sections describe call progression with a script in greater detail.
Starting conditions
Before the script takes control, the following sequence of conditions must be met: 
- A caller dials and reaches the incoming telephone facility for the system. 
 - The software recognizes the ringing condition. 
 - AD checks an internal table to determine the script to run for the call. 
 - All script memory is set to zero and the time-outs are set to their default values.
 
Script control
When all the starting conditions are met, the script takes control and typically executes the following functions during the call: 
- Answer the incoming line (takes it off hook).
 - Send recorded voice messages to the caller. 
 - Listen to touch-tone signals. 
 - Obtain information from the host or from the disk.
 - Send information to a host or a local database.
 - Record transaction events on disk.
 - Take action when a caller does not respond.
 - Signal a termination condition to TSM.
 
TSM control
TSM terminates an active script if one of the following conditions exists:
- The script executes a quit instruction.
 - The maintenance software provides commands to seize control of equipment at any time, thereby terminating transactions on one or more channels without notice.
 - A program error causes a script to terminate, such as when a goto or quit is missing after the last instruction.
 
Script termination
When the script ends, TSM performs the following functions: 
- Put the telephone line on hook if the script did not disconnect.
 - Stop voice play.
 - Discard any pending messages from the host. 
 - Send the CDH a message about the transaction and a copy of the event memory. 
 - Release the channel to AD so it is available for the next call.