4.4 DTMF Interaction

 (Page 5 of 8 in this chapter)
When initiating a voice function, the application can program the AG board to terminate the function when a DTMF key is depressed by the remote party. By default, the AG board terminates play and record when any DTMF key is entered. The respective parameter structure provides a selective DTMF abort mask specifying which DTMF keys terminate the function.

The DTMF abort mask is a 16-bit entity where each bit corresponds to a specific key. Setting a bit in the mask causes the voice function to terminate if that particular key is entered. 



MSB





































LSB





Bit Pos




15




14




13




12




11




10




9




8




7




6




5




4




3




2




1




0





DTMF Key




D




C




B




A




#




*




9




8




7




6




5




4




3




2




1




0









For example, if the abort mask is set to 0x03FF, the play and record functions will 
terminate if a digit from `0' through `9' is entered by the remote party. The 
adidef.h include file contains #defines (ADI_DTMF_xxx) for each digit and certain 
digit groups.




Note: The DTMF abort mask has no effect on the digit collection functions.









    (Page 5 of 8 in this chapter)




Copyright 1996 Natural MicroSystems, Inc.  All Rights Reserved.