Specifications

SIM900 AT Commands Set
SIM900_ATC_V1.01 154 23.06.2010
z The equation of <level> and duty factor is: duty factor = (level+1).
6.2.47 AT+ECHO Echo Cancellation Control
AT+ECHO Echo Cancellation Control
Response :
+ECHO (list of supported < mic>s, list of supported < es>s, list of
supported < ses>s),(list of supported < mic>s, list of supported < es>s, list
of supported < ses>s),(list of supported < mic>s, list of supported < es>s,
list of supported < ses>s)
OK
Read Command
AT+ECHO?
Parameters
See Write Command
Response :
+ECHO: MIC:(0,1,2), ES:(0-6) , SES: (0-4)
OK
Test Command
AT+ECHO=?
Parameters
See Write Command
Response :
OK
ERROR
Write Command
AT+ECHO=
<mic>,<es>[,<ses
>]
Parameters
< mic > audio channel
0 main audio handset channel
1 aux audio headset channel
2 main audio handfree channel
<es> echo suppression
0-6 (when mic=0or1 default value is 0; when mic=2 default value
is 2 )
<ses> selective echo suppression
0-4 (when mic=0or1 default value is 0; when mic=2 default value
is 2)
Reference Note