How do I connect a HC-SR04 ultrasonic sensor?

giuliomoro Sorry, yes my page didn't update before I wrote again in a panic I tested that code you linked to and it is working again! Thank you!! Edit away... Got that code saved this time...!

I do not think I have ever updated my core code! Is there a description of that on the bela guides?

And on running the version check it's "Bela image, v0.3.6b, 23 October 2018"

Sound quality is suddenly very bad even though it's running the same PD patch & audio files... Not sure what could have changed there...

hmm. Do you get error messages in the console?

Unicorpse And on running the version check it's "Bela image, v0.3.6b, 23 October 2018"

Oh that's sad: I believe a fix to a problem similar to the one you reported (content of the file disappearing) was fixed around March 2018, so the above tells us that you already have the fix in your code, which means we should start chasing a new bug.

giuliomoro Ah ok, that is sad hopefully it helps hone down the issue though!

Also now seeing these errors, may have seen some of these previously with the old code but not sure:

Too many messages have been printed to the console too quickly. Reduce your printing frequency
Underrun detected: 8 blocks dropped
3 mode switches detected on the audio thread!

Unicorpse Too many messages have been printed to the console too quickly. Reduce your printing frequency
Underrun detected: 8 blocks dropped
3 mode switches detected on the audio thread!

if you get these only once at the beginning, then it should be fine. Not sure what else could have changed since then? Can you print the values from the sensors and make sure they are ok?

giuliomoro The sensor values are printing ok so that seems fine.

I just tried to restart the bela & the ide to see if there were any changes and got these errors though, that I've never seen before... Something seems to have gone awry here?

Nov 03 17:17:08 bela stdbuf[740]: make: Leaving directory '/root/Bela'
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Unit entered failed state.
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Failed with result 'exit-code'.
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Service hold-off time over, scheduling restart.
Nov 03 17:17:08 bela systemd[1]: Stopped Run Bela at boot.
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Start request repeated too quickly.
Nov 03 17:17:08 bela systemd[1]: Failed to start Run Bela at boot.
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Unit entered failed state.
Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Failed with result 'exit-code'.

Unicorpse Nov 03 17:17:08 bela systemd[1]: bela_startup.service: Unit entered failed state.

this means that the program that starts at boot has crashed repeatedly shortly after being started. Not sure what the reason for that would be. Try maybe to clean the project (in the project tab), then rebuild it. Then go to the configuration tab and set the startup program to "•none" and then to your program again.

giuliomoro Thanks - I'm not sure how to clean it or what to change...

Do you mean change "Run project on boot" in the Settings tab to "none"? When this is the case the project still runs when started manually but the audio still sounds really bad.

Could it be a settings thing - though I'm not sure what could differ from the old code? The sample rate is set to 22050 just now (for 8 channels) - it must have been that before but the audio sounds stuttery and low quality so could it be related?

Alternatively, if this has happened from nowhere with the code disappearing - has the board failed somewhere?

Unicorpse Alternatively, if this has happened from nowhere with the code disappearing - has the board failed somewhere?

this is very unlikely: the code disappearing is a problem with the editor (IDE), but that has nothing to do with the actual audio processing.

Unicorpse - it must have been that before but the audio sounds stuttery and low quality so could it be related?

can you try to:
- remove all connections to [dac~] in your patch.
- add to the patch

[osc~ 440]
| 
[dac~]

can you hear the sinewave just fine?

oh. Does it work in a new project (without the render.cpp file)?

giuliomoro It doesn't appear to... Not hearing anything. I tested it with a completely blank patch and just that osc too (tried including a "; pd dsp 1" message too, and sending to all 10 channels on the dac~)

[osc~ 440] you mean?
In the example I typed above, it only sends the output to the left audio output, can you try this?

[osc~ 440]
|   |
[dac~]

giuliomoro Yeh that's right, with [osc~ 440]

Do you mean the L output on the molex outs with 2 pins?

Just so you know the situation on my audio side, I'm using the audio capelet so my molex (3-pin) outs just now are 0/1, 2/3, 4/5, 6/7 (which I had taken to be equivalent dac~ outs 3/4, 5/6, 7/8, 9/10 on PD from documentation)

I tried your suggestion though, and still nothing from any of the outs it seems?

Ok this is interesting. I tried rerunning my original patch (with the only dac~ coming from the osc~ 440 ), and using the "Out" 3-pin molex out. The sinewave is playing now but intermittently, cutting out?

Unicorpse The sinewave is playing now but intermittently, cutting out?

Yes, you were supposed to listen to the "out" 3-piin Molex connector. This could be symptom of a bad connection?

Unicorpse But now the audio is fine...?

relieved but losing it

Well that's indeed confusing, but it sounds promising. Is it possible you just had some bad connection which was making the audio sound bad?