To Next Page

To Previous Page

Telit LE910 V2 Series AT Commands

80446ST10707A Rev. 0– 2015-11-03

Mod. 0808 2011-07 Rev.2

Embedded DTMF decoder configuration - #DTMFCFG

DTMFCFG – Embedded DTMF decoder configuration

SELINT 2

AT#DTMFCFG=<scaling>

,<threshold_1>,<threshold_

2>[,<std_twist>,<rev_twist>]

Set command allows configuration of the embedded DTMF decoder.

Parameters:

<scaling>:

3..11 – this is the scaling applied to the pcm samples in order to

manage arithmetic operations. The default value is 7.

<threshold_1>:

1000..20000 – this is the numeric threshold used to detect DTMF

tones. The default value is 2500.

<threshold_2>:

1000..20000 – this is the numeric threshold used to start DTMF

decoding. The default value is 1500.

<std_twist>:

0..20 – standard twist threshold. It is an optional parameter and the

default value is 9.

<rev_twist >:

0..20 – reverse twist threshold. It is an optional parameter and the

default value is 5.

Note: The default values were chosen after a fine tuning, so

every change should be done very carefully to avoid wrong

decoding.

Note: the values set by command are not saved and a software or

hardware reset restores the default value.

Note: Default values are referred to standard DMTF decoder

(AT#DTMF=1).

Note: It is supposed that the module is just powered on and the

AT#DTMFCFG command is entered without < std_twist> and

<rev_twist> parameters. In this case the read command doesn’t

return the setting of the <std_twist> and <rev_twist> in order to

meet retro compatibility with other families. Now, let’s assume that

AT#DTMFCFG command is entered again, but using the <

Telit Wireless Solutions LE910 User Manual

Questions and Answers: