Data Sheet
     Smart Machine Smart Decision 
SIM800 Series_AT Command Manual_V1.09  177  2015-08-03 
+ECHO: (0,1),(0-65535),(0-65535),(0-65535),(0-65535),(0,1) 
OK 
AT+ECHO=? 
Parameters 
See Write Command 
Response 
+ECHO: (<mic0>,<nlp0>, <aec0>,<nr0>, <ns0>),(<micn>,<nlpn>, 
<aecn>,<nrn>, <nsn>) 
OK 
Read Command 
AT+ECHO? 
Parameters 
See Write Command 
Response 
OK 
If error is related to ME functionality: 
+CME ERROR: <err> 
Write Command 
AT+ECHO=<mi
c>,<nlp>,<aec>,<
nr>,<ns>[,<state
>] 
Parameters 
<mic> Audio channel 
0 Main audio handset channel 
1 Main audio handfree channel 
<nlp>  Nonlinear processing remove residual echo and background 
noise 
<aec>  Acoustic echo cancellation 
<nr> Noise reduction 
<ns> Noise suppression 
<state>  Enable or disable to close echo algorithm 
0 Echo algorithm be closed 
1 Echo algorithm be actived 
Parameter Saving 
Mode 
AUTO_SAVE 
Max Response 
Time 
- 
Reference Note 
For this command, please refer to actual model. 
The default state the echo echo algorithm be actived, and the read command 
is not displayed. 
6.2.43 AT+CAAS    Control Auto Audio Switch 
AT+CAAS    Control Auto Audio Switch 
Test Command 
AT+CAAS=? 
Response 
+CAAS: (0-2) 










