Colecovision sound stutters

[mediamogul]

@raymate

The author of CoolCV is aware of the situation and has shown possible recent interest in updating the software with a few new features. If that happens, I'm sure he will address this slow down on the Pi as well. Be sure to watch this space for updates.

[raymate]

@mediamogul Good stuff, thanks for the info and reply

[BuZz]

I have been debugging this, and it is the sdl2.0.5 update that has caused the issue.

Unfortunately as it is closed source, I am unable to debug it further (at least debugging coolcv), and don't know what in SDL2 would have affected it as other SDL2 apps seem ok. (Changed my mind - I can debug SDL of course)

[mediamogul]

@BuZz

Thanks for taking the time to look into this. I've passed the information along to the developer here.

[BuZz]

It's quite likely it's an issue with SDL2.0.5 (SDL 2.0.5 has had heaps of problems on the rpi) - I am going to try and git bisect it, but this will take some time.

If I find the commit in SDL, I will revert it or backport any fix if there is one. If I can't (and the coolcv author cannot work around it), I may be forced to switch back to SDL2.0.4 again...

[BuZz]

I have found the commit that causes the issue (this references our git mirror, not the original repository)

commit f0a9a821497b8e9d3e2496a5c5ab844cdddc5e4c
Author: Sam Lantinga <slouken@libsdl.org>
Date:   Wed Oct 12 22:25:19 2016 -0700

    Work-around for a hang when USB devices are unplugged, contributed by James Zipperer

diff --git a/src/audio/alsa/SDL_alsa_audio.c b/src/audio/alsa/SDL_alsa_audio.c
index 3fdbd82..574d51b 100644
--- a/src/audio/alsa/SDL_alsa_audio.c
+++ b/src/audio/alsa/SDL_alsa_audio.c
@@ -314,9 +314,20 @@ ALSA_PlayDevice(_THIS)
     swizzle_alsa_channels(this, this->hidden->mixbuf, frames_left);
 
     while ( frames_left > 0 && SDL_AtomicGet(&this->enabled) ) {
-        /* !!! FIXME: This works, but needs more testing before going live */
-        /* ALSA_snd_pcm_wait(this->hidden->pcm_handle, -1); */
-        int status = ALSA_snd_pcm_writei(this->hidden->pcm_handle,
+        int status;
+
+        /* This wait is a work-around for a hang when USB devices are
+           unplugged.  Normally it should not result in any waiting,
+           but in the case of a USB unplug, it serves as a way to
+           join the playback thread after the timeout occurs */
+        status = ALSA_snd_pcm_wait(this->hidden->pcm_handle, 1000);
+        if (status == 0) {
+            /*fprintf(stderr, "ALSA timeout waiting for available buffer space\n");*/
+            SDL_OpenedAudioDeviceDisconnected(this);
+            return;
+        }
+
+        status = ALSA_snd_pcm_writei(this->hidden->pcm_handle,
                                          sample_buf, frames_left);
 
         if (status < 0) {

I will see if this has been changed in newer versions and either revert or update.

[BuZz]

Please can you update retropie-setup and update coolcv and let me know if that sorts it (I reverted the problematic commit in sdl2).

[BuZz]

Issue has been reported upstream to sdl here - https://bugzilla.libsdl.org/show_bug.cgi?id=3599

[barbudreadmon]

I'll try to fix fbalpha-libretro's colecovision inputs soon, that way you'll have an alternative to CoolCV.

[BuZz]

@barbudreadmon that would be great :) thanks.

[mediamogul]

@BuZz

Everything is back up to speed and performing beautifully. It really does amaze me that a problem like this can be zeroed in on among an ocean of possible causes and rectified. Also, I know it doesn't "just happen", so again I thank you for taking the time to do this.

@barbudreadmon

I'll try to fix fbalpha-libretro's colecovision inputs soon, that way you'll have an alternative to CoolCV.

That would be fantastic! Thank you.

[EVEGames]

@mediamogul , does that mean there is a new CoolCV binary to be had, with these fixes in place? What would be our best way to get it installed over the top of our existing CoolCV?
Thanks!

[mediamogul]

@EVEGames

There's no new binary, but BuZz fixed the root of the problem and it can be applied by using the 'Update from Binary' option for CoolCV in the RetroPie-Setup.

[dman2552]

Is anyone else here running a USB sound device with CoolCV? It seems as long as my rpi3 is configured for USB sound, my screen goes blank and becomes unresponsive to any connected keyboard/controllers when I try to play any CV game (even launching a game from command line). I have to SSH in to reboot. This happens with a fresh 4.1 install to the latest 4.1.18 update with sound fix. So far everything else I use RetroPie for is fine.

[raymate]

Sounds good, I updated from binary (think I did) and it didnt seem to change, I'm sure Im doing it wrong.

For the newbies out here may just give us a quick guide.

[BuZz]

@raymate you didn't update retropie-setup.

[mediamogul]

My bad. I forgot to reiterate that above.

[mediamogul]

@dman2552

my screen goes blank and becomes unresponsive to any connected keyboard/controllers when I try to play any CV game

I can't speak to the keyboard controls, but you might try adding the following to /opt/retropie/configs/all/runcommand-onstart.sh and see if it solves the screen issue. It was used to solve a similar issue in Kodi a while back and may work here.

if [ "$2" = "coolcv" ]
then
fbset -depth 8
fbset -depth 32
fi

[raymate]

OK did from script and it works, sound normal. Perfect thank to all your hard work

[dman2552]

@mediamogul said in Colecovision sound stutters:

@dman2552

my screen goes blank and becomes unresponsive to any connected keyboard/controllers when I try to play any CV game

I can't speak to the keyboard controls, but you might try adding the following to /opt/retropie/configs/all/runcommand-onstart.sh and see if it solves the screen issue. It was used to solve a similar issue in Kodi a while back and may work here.

if [ "$2" = "coolcv" ]
then
fbset -depth 8
fbset -depth 32
fi

I tried as you suggested but it didn't work. I did find out what the problem was. I used the /etc/modprobe.d/alsa-base.conf method of setting the sound device but had to use the /etc/asound.conf method. All seems to be working great now.

Thanks.