How do I connect a HC-SR04 ultrasonic sensor?

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?

giuliomoro Thanks that's reassuring at least!

Ok I tried that - osc works fine as a standalone patch on my laptop (of course), but interestingly, when it's uploaded to the Bela there is no sound?

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?