Dialogic Technical Information

NOTE:  The Intel Dialogic product line was sold to Eicon (which then renamed itself to Dialogic Corporation).  Product information and technical information on the Dialogic site was in flux for quite some time. Some links to Intel included on the ExceleTel web site may no longer be available.  Please search www.dialogic.com for updated information.

Please note that most of the information on this page applies to the original "Dialogic" product line.  Eicon (now renamed to Dialogic) also has the Diva product line that supports the Windows Telephony API (TAPI).

TAPI Compatible Board List - (www.exceletel.com)
Product Information - (www.dialogic.com)
Hardware Quick Install Guides


Sample Programs

Technical Notes

Dial Tone Detection
Early Connect
Important Property Settings
Outbound Calls
Unformatting Phone Numbers
Volume Settings
Working With Wave Files

Customer Successes


For use with TAPI and TeleTools it is advisable to use Dialogic System Release 5.1.1 with SU 149 (includes SP 1 and FP 1).  Dialogic System Release 5.1.1 with SP 1 and the D4PCIU patch (plus some special procedures in some cases) should also work.  If you are using digital boards (T1, etc.) you will also need the Global Call Protocols Package.

If you need the Dialogic installation files and are or wish to become an ExceleTel customer, please contact us by phone (+1-919-233-2232) or email (sales (at) exceletel.com).

As of March 4, 2003 Intel Dialogic is now providing support for installing on Windows XP.  According to Intel Dialogic, this requires System Release 5.1.1 Feature Pack 1 (FP1) for Windows.  However, if necessary ExceleTel can normally help customers get Dialogic boards running on both Windows XP and Windows 2003 without FP1 or SR6.  Please contact us to set up a support session.

The Dialogic System Release 5.1.1 Release Guide states that 5.1.1 will be the last release that supports ISA boards. This information was obtained from System Release 5.1.1 for Windows Release Guide.

Alternative software development tools for Intel / Dialogic hardware

   Less costly
   Royalty Free
   Hardware Independent

Would you like to find an alternative to the expensive, royalty based, hardware specific, and/or discontinued  computer telephony software development tools from Intel / Dialogic, Pronexus, Parity, Envox or others? Click here for more information about ExceleTel TeleTools.

  Artisosft VisualVoice
Parity CallSuite
Parity VOS
Pronexus VBVoice
CT ADE (Dialogic, Intel,  Envox)

Do you need a replacement for one of these or one of the others like them?  Click here to download ExceleTel TeleTools trial software now.

You may also contact us directly to get help or more information about replacing your current computer telephony software development tool.

ExceleTel Inc.

Hardware Quick Install Guides


Fortunately the Dialogic boards and drivers are dependable (although a bit picky about certain event sequences and timing).  Unfortunately the documentation for installing them is unclear.  For this reason we are supplying these documents to aid in their installation and configuration.  These documents will help you configure your Dialogic board for use with Microsoft’s Telephony Application Programming Interface (TAPI) and ExceleTel TeleTools. You should still follow the instructions supplied with your Dialogic board. These documents will help to guide you through that mountain of information.  If you need additional help, please contact us to set up support arrangements.

Be sure to install the Dialogic TAPI drivers and the Dialogic sample programs. The Dialogic sample programs are handy for making sure that the drivers and the board are working properly. It is important to know that "Talker32.exe" is the only Dialogic sample program that uses TAPI. All other Dialogic sample programs work directly with the Dialogic low level drivers and their proprietary API.



Dialogic home page (www.dialogic.com).

Click here to see the GlobalCall E-1/T-1 Technology User's Guide

Click here for complete online documentation for Intel Dialogic cards and Driver information


Sample Programs

Click here for a complete list available sample programs provided by ExceleTel.

Here is a list of sample programs written specifically for Intel / Dialogic cards:


Answer calls and forward them to to another number.  Create agent systems, customer support solutions, allow customers to press a digit and be connected to a representative, conference lines together and more. Lets you duplicate PBX functions with only a dialogic card.  


This sample program illustrates how to work with Dialogic cards to make outbound telephone calls and deals with issues related to detecting dialtone on Dialogic cards


The IVR4Line sample program demonstrates one method of building an application that supports multiple telephone devices simultaneously. It is a simple Interactive Voice Response system (IVR) that automatically answers incoming calls, plays and records wave files and responds to DTMF tones.  In addition, this sample program demonstrates how to read back the CallerID number to the caller.


This program is the same as etIVR4Line except that it shows how to play wave files loaded into memory buffers as opposed to using disk files.


The etTransfer sample program demonstrates how to perform a supervised transfer, also know as a consultation transfer.


Technical Notes

Dial Tone Detection

When working with an Intel / Dialogic card The etLine.OnDialtone event will fire even when a dial tone isn't present. To test for a dial tone you have to set the property etLine.Call.PhoneNumber to a blank string then call etLine.Call.Dial. In the etLine.OnDialtone event handler routine you then set etLine.Call.PhoneNumber to "L" + the phone number (for example "L19192332232") then execute etLine.Call.Dial again. If the etLine.OnDisconnected event fires and the etLine.Call.DisconnectMode is set to LINEDISCONNECTMODE_NODIALTONE then you know that you do not have a dial tone. You can see all of this in the etDialogicDial sample program.

An easier way, depending on your application is to dial a call and detect the TeleTools OnSpecialInfo event and read the etLine.CallSpecialInfo property.  Dialogic will report no dialtone as LINESPECIALINFO_NOCIRCUIT.  Technically, this is not correct since the TAPI spec designed this to report a NO_CIRCUIT SIT tone which is received when you call a number and there is no circuit on that end.  If you need to know the difference between these events, you could use a timer, or check other call progress identifiers like "ringback" to see if it occurred before you got the message.

Early Connect

In some situations Dialogic cards may detect remote party connections incorrectly. Sometimes this can be overcome by increasing the Ring back Timeout. The default value is 700. Try increasing this by 100 or 200 until the problem goes away.

If increasing the value to more than 2000 does not solve the problem then set the number back to 700 and modify the Call Progress Analysis Flags.

The Call Progress Analysis Flags work in conjunction with PerfectCall. You will not want to enabled "Positive Answering Machine Detection" because even Dialogic says it doesn't work right. Your best bet would be to try using "DX_PVDENABLE(4).

For detailed information open the Dialogic Master.chm help file and search for "Perfect Call". You will need to look at checking the "DX_" options.

In some cases you may need to turn off Perfect Call.

The Ringback Timeout and Call Progress Analysis Flags can be found on the Call Parameters tab of the Configuration Service dialog box for the Dialogic Telephony Service Provider.

You will need to reboot for the changes to take effect.

DIGITAL BOARD USERS: Digital systems do not fire OnConnected in the same way as analog cards.  It is normal for the OnConnected event to fire as soon as the CO sets the A and B bits high. Instead of looking at
Connected states, look for Call Progress Analysis states.

D4 BOARD USERS: The D4 in some machines will simply not reliably detect voice to fire the OnConnected event.  In this case, you will have to use the D41 series.  

Important Property Settings

The following settings are the defaults. When working with Intel Dialogic cards do not change these values, Dialogic does not support them!:

  •  etPlay.Device.Delay = 0 

  •  etPlay.Device.Wait = False

  •  etPlay.Device.Loop = False

Unformatting Phone Numbers

The Intel / Dialogic drivers do not understand how to dial phone numbers with formatting characters, you will receive a LINEERR_INVALADDRESS error (TAPI refers to a phone number or other identifier for a called party such as IP address as an "address").  For example:

1 (315) 635-3426

To avoid this problem set the etLine.Device.UnformatPhoneNumber property to True.  This will cause all formatting characters to be removed prior to dialing.

Another option is to use canonical formatted phone numbers and set the etLine.Device.TranslatePhoneNumber property to True.  When this property is set to True and the phone number is in canonical format then TeleTools will convert the value according to the Windows Dialing Properties.  For example:

Entered as

Converted to

+1 (315) 635-3426 T9 13156353426
+1 (919) 555-1212 T95551212
1.315.635.3426 T1.315.635.3426
213 T213

Volume Settings

Dialogic does not have a configuration setting for the volume level. You need to set the etPlay.Volume properties. You can find information on this topic in the help file. Try the following values:

Borland C++ Builder

etPlay1->Volume->Enabled = True;   
etPlay1->Volume->Default = False; 
etPlay1->Volume->Reset = False; 
etPlay1->Volume->Position = 75;  

Borland Delphi

etPlay1.Volume.Enabled := True;
etPlay1.Volume.Default := False;
etPlay1.Volume.Reset := False;
etPlay1.Volume.Position := 75;

Visual Basic 5 & 6

etPlay1.VolumeEnabled = True
etPlay1.VolumeDefault = False
etPlay1.VolumeReset = False
etPlay1.VolumePosition = 75

Working with WAV Files

Click here for detailed information about playing and recording wave files.

Please note that Dialogic has several unresolved bugs for which there are workarounds.  As noted above, the "loop" capability is not properly implemented and can even lock the Dialogic TSP.  You must manually do this with etPlay.

Dialogic supports only the following wave formats natively:

  • 11kHz, 8bit, Mono - main format and best quality

  • 8kHz, 8bit, Mono - seems to be supported on newer cards 

 Unless you enable CODECS in etPlay and etRecord, you will receive an error trying to use another format

We have converted the wave files utilized by many of the TeleTools sample programs to a format that many Intel / Dialogic cards support natively, 11k8bitmono.zip.



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Copyright(c) 2003-2008 ExceleTel Inc
support (at) exceletel.com