Hiwonder Carrier Board

Product Overview

This carrier board integrates multiple peripherals. The following are instructions for using the audio section.

Installation

• Hardware Deployment

Refer to other audio boards for connection. Connect using the 40-pin to 40-pin interface.

• Software Configuration

1. Use srpi-config to configure the audio board.
   Go to 3 Interface Options -> I5 Audio
   Select Hiwonder Audio Driver HAT:

2. Follow the prompts to execute the reboot command, or run sync && reboot to restart the board. If cat /proc/asound/cards shows the duplexaudioi2s1 sound card, the carrier board is installed successfully.

root@ubuntu:~# cat /proc/asound/cards 
 0 [duplexaudioi2s1]: simple-card - duplex-audio-i2s1
            duplex-audio-i2s1
 1 [duplexaudio    ]: simple-card - duplex-audio
            duplex-audio

• Uninstallation

1. Use srpi-config to configure the audio board.
   Go to 3 Interface Options -> I5 Audio
   Select UNSET to uninstall the audio driver and related configurations.

2. Remove the carrier board.

Usage

Check if the sound card exists and verify the device number.

To confirm the sound card is registered (as mentioned above):

root@ubuntu:~# cat /proc/asound/cards 
 0 [duplexaudioi2s1]: simple-card - duplex-audio-i2s1
            duplex-audio-i2s1
 1 [duplexaudio    ]: simple-card - duplex-audio
            duplex-audio

To check logical devices:

root@ubuntu:~# cat /proc/asound/devices
  2: [ 0- 0]: digital audio playback
  3: [ 0- 1]: digital audio capture
  4: [ 0]   : control
  5: [ 1- 0]: digital audio playback
  6: [ 1- 0]: digital audio capture
  7: [ 1]   : control
 33:        : timer

To check actual device files in user space:

root@ubuntu:~# ls /dev/snd/
by-path  controlC0  controlC1  pcmC0D0p  pcmC0D1c  pcmC1D0c  pcmC1D0p  timer

Based on the above and the onboard Earphone audio port documentation, sound card 0 corresponds to the Hiwonder Audio Driver HAT node; the devices exist, with device numbers 0-0 and 0-1. The actual devices to operate are pcmC0D0p and pcmC0D1c.

The onboard sound card corresponds to 1, with device number 1-0, which is not used here.

• Recording

Use the following command to record audio:

arecord -Dhw:0,0 -c 2 -r 48000 -f S32_LE -t wav -d 10 /userdata/record1.wav

• Playback

Use the following command to play back the recorded audio:

aplay -D hw:0,0 /userdata/record1.wav

FAQ

See the following link for more information