BTCDU.VBX - Caller Display

Add Caller Line Identification (CLI) and Caller Telephony Integration (CTI) to your apps

The BTCDU.VBX contains a single data-aware custom control designed to add both these features to your applications. This easy to use Control, is data-aware and uses the incoming call telephone number to index into either a specifically designed database, or an existing database to which a telephone number field has been added.

Using other data-aware controls, linked to fields in the same database, it is a simple matter to display these fields in any required format with very little coding, when a telephone call is received. No knowledge of the CLI protocol (Calling Line Identification), or Serial Communications is necessary, as both of these are handled by the Control. The Control is also fully 'Event Driven' requiring no 'Polling' by the application using the Control.

The Control is designed for use with PC Serial Port CLIP compliant hardware, a list of suppliers is given in an Appendix in the main documentation Help file. The Control uses the Microsoft Data Control to link to the relevant database and hence can link to any database that is supported by the Data Control. The Microsoft Advanced Data Control is recommended for use with networked databases.

Add this Control to your application and immediately gain the benefit of both CLI and CTI with very little coding effort, e.g. Help Desk applications. The Control currently works with Visual Basic 3.0 and 4.0 (16 Bit), with 32 Bit OCX and Delphi Visual Components to be released shortly.

The Control consists of 18 Custom Properties and 5 Custom Events, some of which are highlighted below:

• CallReceived Event - This Event is triggered when a Call is received. All CLIP data received with the call is made available to this Event.
• Error Event - Errors encountered when using the Control can be handled by this Event, or passed to Visual Basic and handled via normal Error Trapping techniques, e.g. ON ERROR GOTO.
• allSaved Event - This Event is Triggered whenever a received calls is Saved to memory, and also when a saved call is subsequently Retrieved from memory. Both Answered and Unanswered calls can be selectively Saved to memory using the SaveCall property.
• allStatus Property - This property indicates the type of call received; it currently takes on one of 3 values: 1. No telephone number available. 2 .Telephone Number received, but no record found in linked database. 3. Record found in linked database. Based on the status, the application can determine what action to take.
• CommPort Property - The Control can use Communications ports 1 to 4. This allows multiple Controls to be used in the same application linked to the same or different databases, or multiple instances of the same application linked to the same or different databases or just different applications, linked to the same or different databases.
• Note: In most cases, the use of multiple controls will require more than one communications port, telephone connection and CLIP hardware.
• SaveCall Property - Save Answered and Unanswered calls. Calls are saved in a linked list in memory, and may be easily recalled using the CallRetrieve Property.
• CallRetrieve Property - Retrieve previously Saved Calls. Saved Calls may be retrieved as follows: First Call, Last Call, Next Call, Previous Call, Delete All Saved Calls. The data retrieved from a Saved Call is exactly the same as that received with the original call, including the CallStatus Property value. The CallSaved Event is generated when a call is both Saved and subsequently Retrieved.
• Enable Property - Used to connect and disconnect from the Communications Port. Can be used to free the communications port for use by other applications.
• Link Property - Always contains the last telephone number received, or it contains the telephone number of the last call retrieved from the list of saved calls.
• LogCall Property - All incoming calls can be saved to a Log File in 'Comma Delimited Format', (LogFileName Property) for analysis by other applications. Changing the LogFileName Property allows the maintenance of mutiple Log Files.
• TransmitData Property - This property allows such actions as 'Calling Back' any saved call using the Link Property as the telephone number obtained using the CallRetrieve Property.
• CaptureCall - Capture any incoming call in CLIP format for use when testing applications. See Development Tools later.

Please see the main Help File documentation for the remaining Custom Properties and Events.

An extensive range of development tools is included with the package, including:

1. BUILDCLI.EXE - Build your own telephone calls in CLIP format for testing your application. 2. TX.EXE - Transmit Captured or Built calls from a second PC using a NULL Modem cable. Cable spec.is supplied. 3. TXERR.EXE - As TX.EXE but truncates the call data to simulate Lost Data in a received call.

One of the example applications included with the package, CallBack.exe, is a direct replacement for the BT Caller Display (including the telephone version) with the added benefit of Callback on any Saved Call and the ability to display additional information from a linked database. This example has a maximum of 50 saved calls but this could be increased to a current maximum of 1000 calls !!!

The example program Demo.exe, in conjunction with a Wrap Plug, shows how to test applications using the Control, without the need for the CLIP compliant hardware. The demonstration version of the Control is protected as follows : 200 Call Limit, Demonstration Licence (.LIC) file, Nag Screen. None of these are present in the Retail version.