FAQ¶
The system is abnormally stuck or restarted¶
The current of power supply may not be enough, the Working voltage of board is 5V and the working current is over 500mA, depending on the specific mounted peripherals.
The sound of the headphones is too small¶
Check the codec output gains in current left and right channels:
amixer cget name='DAC HPOUT Left Volume'
amixer cget name='DAC HPOUT Right Volume'
Adjust the base gain as needed:
amixer cset name='DAC HPOUT Left Volume' 18
amixer cset name='DAC HPOUT Right Volume' 18
Adjust the volume (percentage):
amixer cset name='Master Playback Volume' 40
recording¶
Capture 6-Mic record and 2-mic recovery audio data:
arecord -D hw:0,0 -c 8 -r 16000 -f S16_LE test.wav
Increase audio input gain:
export ALSA_LIB_ADD_GAIN=3
The PDM microphone array of ROC-RK3308-CC does not have the hardware registers, so, before the recording, you can run the above command, shift the amplified audio data to the left, and the number 4 on the right represents the number of digits shifted to the left.
When the sample rate is greater than 16000hz, the recording command should be followed by the parameter --period-size=1024 --buffer-size=4096
, for example:
arecord -D hw:0,0 -c 8 -r 44100 -f S16_LE --period-size=1024 --buffer-size=4096 test.wav
Firmware burning¶
If you burn firmware fails.
You can download the Official Firmware and burn this firmware in your device at Maskrom mode to resume your device.
Or, you can try it again on Windows with AndroidTool.
Speech recognition Commercial development¶
As for the major ASR sdks supported by the ROC-RK3308-CC open-source motherboard, customers need to communicate with their own R&D company if they need more in-depth cooperation of customized services.
Startup after booting¶
Directly modify the startup script in ROC-RK3308-CC and add your own commands.
vi /oem/RkLunch.sh
When burning partition image separately, a partition address error occurred¶
When loading parameter.txt, AndroidTool will automatically distribute partition address according to parameter. When the partition image is burned separately, the parameter.txt will be loaded simultaneously, so there’s no need to manually modify the partition address.