A20_olinuxin_micro: diff between Olimex Debian images and those of Debian

[MatN]

What extra features does the Olimex Debian image offer compared to Debian?
I'm mostly interested in sound and video.

[LubOlimex]

There are just configurations for our boards to ensure that most of their hardware features are well supported in the Linux. Some scripts that allow to transfer Linux to eMMC or harddisk or to have LCD and HDMI output and such. The sound and video input are as they come from the original sources, for example we don't apply patches that improve the video output. You should check this document:

https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf

For better video output you might consider the older sunxi images, but they have some binary blobs related to the video.

[MatN]

Very useful document, thanks. I'm running with an Olimex 7 inch touch screen LCD only, Why don't I have sound? The OS is Debian 11 a20-olinuxino 5.10.105-olimex . It loads the lima screen driver OK. Is there some config somewhere that is needed for sound output?
- inxi reports:  Sound Server: ALSA v: k5.10.105-olimex .
- aplay -L reports:
hw:CARD=sun4icodec,DEV=0
    sun4i-codec, CDC PCM Codec-0
    Direct hardware device without any conversions
plughw:CARD=sun4icodec,DEV=0
    sun4i-codec, CDC PCM Codec-0
    Hardware device with all software conversions
sysdefault:CARD=sun4icodec
    sun4i-codec, CDC PCM Codec-0
    Default Audio Device
dmix:CARD=sun4icodec,DEV=0
    sun4i-codec, CDC PCM Codec-0
    Direct sample mixing device
usbstream:CARD=sun4icodec
    sun4i-codec
    USB Stream Output

[LubOlimex]

The sound is supposed to work with mainline images.

1) Which board and board revision do you have exactly?

2) Which of the two images here are you using exactly (base or minimal): https://images.olimex.com/release/a20/

3) What audio output device do you connect to the board? Does it use standard 3.5mm audio jack?

4) How do you test the audio exactly? If via command line what exactly are you typing?

[MatN]

1: Board is A20-olinuxino-micro 4G from 2014. Board rev F. Screen LCD7TS, 500g sata disk, usb-serial cable. psu 12v/0.5A
2: Last full new system was A20-OLinuXino-bullseye-base-20211130-145129.img.7z , since kept up to date from Debian repos with apt update/upgrade.
However, I cannot find the "change_display" script mentioned in the manual, neither in the image or the installed system. Manual A20-OLinuXino-Micro.pdf (rev S, March 2018). That script is also not in A20-OLinuXino-bullseye-base-20220928-143706.img .
3: Audio out to headphone/lineout mini jack. Neither headphone or active speakers give any sound.
4. I use the simplest audio test cmd I could find, in terminal: "speaker-test -c 2", stop with ctrl-C.
Command "amixer output shows volume not set to zero:
olimex@a20-olinuxino:~$ amixer
Simple mixer control 'Master',0
  Capabilities: pvolume pswitch pswitch-joined
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 65536
  Mono:
  Front Left: Playback 62275 [95%] [on]
  Front Right: Playback 62275 [95%] [on]
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch cswitch-joined
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 65536
  Front Left: Capture 47708 [73%] [on]
  Front Right: Capture 47708 [73%] [on]

MatN

[LubOlimex]

Alright I will carry some tests with similar configuration.

The scripts in latest Olimage mainline images scripts are slightly different compared to the sunxi images, for the display it is "olinuxino-display".

I recommend you this document which explains Olimage Linux: https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf

[LubOlimex]

This test "speaker-test -c 2" produces some terrible noise here, it alternates between left and right channel. So it probably works.

Better test with some wav or mp3 file, and "aplay 1.wav". If you use flash drive for the song, remember to mount it.

I used latest image since we don't keep older releases, so my advice is to download the latest "base" image on another card and test. From here: https://images.olimex.com/release/a20/

Maybe something broke between the updates in your image.

[MatN]

I put the latest A20-OLinuXino-bullseye-base-20220928-143706.img on another sd card, and without configuring the LCD, via the usb-serial cable speaker-test and playing .wav works. So fortunately my hardware is OK. After configuring the LCD it still works.
I will start again from this latest image, and compare configs with the old, hopefully I can find what caused the problem.

Thanks you for the assistance.

MatN
PS If you don't like the speaker-test pink noise :-) , use "speaket-test -c 2 -t wav"