SIM5218E Hardware Design
stGain
Digital attenuation of
sidetone
0, 1...65535 Mute,
-96...0dB
20 * log
(stGain/
16384) -12
AT+CSIDET
rxFilter
Output PCM 13-tap filter
parameters, 7 values
0...65535
---
MATLAB
calculate
AT+CRXFTR
NOTE: if user want to better experience on audio, user should modify these parameters for
user’s own electronic and mechanical
design of audio part. The 13-tap filter parameter could
be debugged and calculated by MATLAB.
3.8.5.2 Audio Programming Model
The audio programming model shows how the signal path can be influenced by varying AT
command parameters. Parameters <micAmp>, <txGain> , <txVol>, <txFilter>,<rxGain>,
<stGain> ,<rxVol> and <rxFilter> can be adjusted with corresponding AT commands. For more
information on the AT commands and parameters see Section 3.8.5.1.
NOTE: Please reference document [1] for detailed information of each AT command.
Figure 19: Audio programming model
3.8.5.3 Audio characteristics
The electrical characteristics of the voiceband part depend on the current audio mode (device
number) set with the AT+CSDVC command. All values are noted for default gains.
SIM5218E_ Hardware Design_V1.06
2012.09.21
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