[arm-allstar] duration of cop 48 dtmf tones

[David McGough]

Hi Robert,

I believe all the telemetry-generated DTMF tones have hard coded lengths
of 200ms of tone, followed by 200ms of silence. There isn't a way to
change this without recompiling Asterisk/AllStar, as far as I know.  Here
is the relevant section of code from app_rpt.c:

static char* dtmf_tones[] = {
        "!941+1336/200,!0/200",		/* 0 */
        "!697+1209/200,!0/200",		/* 1 */
        "!697+1336/200,!0/200",		/* 2 */
        "!697+1477/200,!0/200",		/* 3 */
        "!770+1209/200,!0/200",		/* 4 */
        "!770+1336/200,!0/200",		/* 5 */
        "!770+1477/200,!0/200",		/* 6 */
        "!852+1209/200,!0/200",		/* 7 */
        "!852+1336/200,!0/200",		/* 8 */
        "!852+1477/200,!0/200",		/* 9 */
        "!697+1633/200,!0/200",		/* A */
        "!770+1633/200,!0/200",		/* B */
        "!852+1633/200,!0/200",		/* C */
        "!941+1633/200,!0/200",		/* D */
        "!941+1209/200,!0/200",		/* * */
        "!941+1477/200,!0/200" };	/* # */


This structure provides data for the ast_playtones_start() function (part 
of the Asterisk core code)....I don't know of a public source of 
documentation for these data format. However, as I understand it, it's 
basically:

"!" ---is the start of a tone sequence.
"," ---separates tone sequences.

freq1+freq2/duration  ---first and second tone freq, duration in millisec.

So: 941+1336/200  means generate 941hz and 1336hz for 200ms.
And: 0/200 means generate no sound for 200ms.

I presume you could adjust the 200ms value to a larger number??? (I
haven't tried this!)...And, then re-compile the source code.

73, David KB4FXC



On Sun, 10 Jan 2016, Robert Conklin wrote:

> Greetings everyone.
> Is it possible to increase the duration of the DTMF tone outputs in a
> COP,48 string?
> --
> Robert Conklin
> *N4WGY <http://qrz.com/db/N4WGY>*
>