Miscellaneous audio commands, Pcm play and receive #spcm, Syntax – Synaccess Networks NP-0801DTM User Manual
Page 323: Parameters and values, Notes

AUDIO COMMANDS
323
HSPA+ AT Commands Reference Guide
Miscellaneous Audio Commands
PCM Play and Receive #SPCM
Execute command allows user either to send speech sample coming from microphone and/or downlink audio
channel to serial port, or to reproduce a PCM coming from serial port to speaker and/or uplink audio channel;
both modes are also available during speech calls.
Test command returns the supported range of values for
#SPCM:
Syntax
Command
Command type
AT#SPCM=
Execute
AT#SPCM=?
Test
Parameters and Values
Action to execute.
1
Reproduce PCM stream from serial to selected path.
2
Send speech from selected path to serial.
Select the audio path.
0
Send/receive to/from analog front end.
1
Send/receive to/from audio channel.
2
Reserved.
PCM bits format.
0
8 bit.
1
16 bit.
Notes
Execute command switches module in online mode. Module moves back to command mode either afer entering
the escape sequence +++ or as a consequence of a DTR transition.
If you are using 16 bit, you must set +IPR at least to 230400.
The following table summarizes the status of audio path during a speech call for different configurations and with
sidetone disabled:
mode = 1
mode = 2
dir = 0
Uplink off. Downlink on.
PCM stream on speaker.
Uplink off. Downlink off.
PCM stream from microphone.
dir = 1
Uplink on. Downlink off.
PCM stream on uplink.
Uplink off. Downlink off.
PCM stream from downlink.
Sidetone is active for default.