I’m trying to use UAC for audio with EG25 LTE module. I enabled UAC with the following two AT commands:
AT+QCFG=“USBCFG”,0x2C7C,0x0125,x,x,x,x,x,x,1
AT+QPCMV=1,2
It seems Linux detects a sound card 4:
pi@NanoPi-NEO-Core:~$ sudo aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: Dummy [Dummy], device 0: Dummy PCM [Dummy PCM]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 1: Loopback [Loopback], device 0: Loopback PCM [Loopback PCM]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 1: Loopback [Loopback], device 1: Loopback PCM [Loopback PCM]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 2: Codec [H3 Audio Codec], device 0: CDC PCM Codec-0 []
Subdevices: 1/1
Subdevice #0: subdevice #0
card 3: allwinnerhdmi [allwinner,hdmi], device 0: 1c22800.i2s-i2s-hifi i2s-hifi-0 []
Subdevices: 1/1
Subdevice #0: subdevice #0
card 4: EG25G [EG25-G], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
I made a voice call with ATD command and tried to play audio over that sound card with the command:
sudo ./src/tinyalsa/utils/tinyplay -D 4 pcm1608m.wav
However I can’t hear anything on the remote phone.
What’s the problem? Isn’t this the correct procedure?
This is my firmware version:
ATI
Quectel
EG25
Revision: EG25GGBR07A08M2G
OK