4.4. Global DPD Application Programming Interface

• 4.4.1. Dial Pulse Detection Digit Type Reporting
• 4.4.2. Defines for Digit Type Reporting
• 4.4.3. GDPD Programming Procedure
• 4.4.4. GDPD Programming Example

Global Dial Pulse Detection uses the same Application Programming Interface (API) model as the standard DPD interface.

The Global DPD feature must be implemented on a call-by-call basis. Global DPD must be enabled for each call by calling dx_setdigtyp( ) for the Global DPD feature to work correctly.

For any digit detected, you can determine the digit type, DTMF, MF, GTD (user-defined) or DPD, by using the DV_DIGIT data structure in the application. When a dx_getdig( ) call is performed, the digits are collected and transferred to the user's digit buffer. The digits are stored as an array inside the DV_DIGIT structure. This method allows you to determine very quickly whether a pulse or DTMF telephone is being used.

4.4.1. Dial Pulse Detection Digit Type Reporting

As shown in the following table, two defines are provided for identifying the Dial Pulse Detection digit type, depending upon how the digit type is retrieved.

#define	Digit Type
DG_DPD	Dial Pulse Detection digit from the DX_EBLK event queue data (cst_data) through a DE_DIGITS Call Status Transition event
DG_DPD_ASCII	Dial Pulse Detection digit from the DV_DIGIT dg_type digit buffer using dx_getdig( )

Obtaining the digit type for DPD digits is valid only in the case when the voice and DPD capabilities are both present on the same board. In the case where a voice board does not support DPD, you cannot detect DPD digits or obtain the DPD digit type even though you can enable DPD and digit type reporting without an error.

4.4.2. Defines for Digit Type Reporting

Several can be used to obtain the DV_DIGIT dg_type (digit type) from the digit buffer. These defines contain "_ASCII" extensions as shown in the following table. If you get the digit from the DV_DIGIT dg_type digit buffer using dx_getdig( ), you should use the digit type define that has the "_ASCII" suffix. Otherwise, if you get the digit from the DX_EBLK event queue data (cst_data) through a DE_DIGITS Call Status Transition event, you should use the digit type define without the "_ASCII" suffix

	Defines for dg_type from
Digit Type	Digit Buffer	Event Queue
DTMF	DG_DTMF_ASCII	DG_DTMF
DPD	DG_DPD_ASCII	DG_DPD
MF	DG_MF_ASCII	DG_MF
GTD (user defined)	DG_USER1_ASCII DG_USER2_ASCII DG_USER3_ASCII DG_USER4_ASCII DG_USER5_ASCII	DG_USER1 DG_USER2 DG_USER3 DG_USER4 DG_USER5
NOTE: Use the defines as shown above to determine the digit type from the value returned in the dg_type digit type field. If you get the digit from the digit buffer by using dx_getdig( ), you should use the digit type define that has the "_ASCII" extension. Otherwise, if you get the digit from the event queue through a DE_DIGITS Call Status Transition event, you should use the digit type define without the "_ASCII" extension.

4.4.3. GDPD Programming Procedure

1. Define a data structure of type DV_DIGIT (the DV_DIGIT structure is specified in the DXDIGIT.H file).
2. Enable DPD on the desired channels using the dx_setdigtyp( ) function. For new calls you must use the D_DPDZ mask that initializes the DPD detector for new calls.
3. Execute the dx_getdig( ) function to collect and transfer the digits to the user's digit buffer. The digits are stored in the dg_value field of the DV_DIGIT structure with the corresponding digit types stored in the dg_type field of the DV_DIGIT structure.

4.4.4. GDPD Programming Example

/*$ dx_setdigtyp( )and dx_getdig( ) example for Global Dial Pulse Detection $*/

#include        <stdio.h>

#include        "srllib.h"

#include        "dxxxlib.h"



void main(int argc, char **argv)

{

   

   int     dev;                    /* Dialogic device handle */

   DV_DIGIT        dig;    

   DV_TPT tpt;  



   /*

    * Open device, make or accept call 

    */



   /* setup TPT to wait for 3 digits and terminate */

   dx_clrtpt(&tpt, 1);

   tpt.tp_type =   IO_EOT;

   tpt.tp_termno = DX_MAXDTMF;

   tpt.tp_length = 3;

   tpt.tp_flags =  TF_MAXDTMF;

   

   /* enable DPD and DTMF digits */

   dx_setdigtyp(dev, D_DPDZ|D_DTMF);



   /* clear the digit buffer */

   dx_clrdigbuf(dev);                      



   /* collect 3 digits from the user */

   if (dx_getdig(dev, &tpt, &dig, EV_SYNC) == -1) {

      /* error, display error message */

      printf("dx_getdig error %d, %s\n", ATDV_LASTERR(dev), ATDV_ERRMSGP(dev));

   } else {

      /* display digits received and digit type */

      printf("Received \"%s\"\n", dig.dg_value);

      printf("Digit type is ");

      /* 

       * digit types have 0x30 ORed with them strip it off

       * so that we can use the DG_xxx equates from the header files

       */

      switch ((dig.dg_type[0] & 0x000f)) {

         case DG_DTMF:

            printf("DTMF\n");

            break;

         case DG_DPD:

            printf("DPD\n");

            break;

         default:

            printf("Unknown, %d\n", (dig.dg_type[0] &0x000f));

      }

   }



   /*

    * continue processing call

    */

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