Took a few nicer pictures in preparation for selling a few of these:
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What kind of push buttons are those? They look cool
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It’s these from Ali Express:
https://m.aliexpress.com/item/33035513753.html
I like them quite a bit.
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More information here, looks like the manufacturer
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I just noticed my design has the push buttons connecting +5 V directly to the inputs. Which is not good, not if there’s a voltage source plugged into the input. I think a 1k added between each input jack tip and the corresponding push button would fix this. (Untested though.)
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@ChristianBloch got guidelines to add this to the Euro version - im sure i could follow the traces just as well lol
Don’t you also need a diode to make an OR gate?
I think it’s OK, if the 1k resistor goes from the input to the junction between the push button and the 100k. When the button is pressed, regardless of the input you have +5 V at that junction so the transistor is turned on. When the button is not pressed it’s floating and the voltage at that junction is (nearly) whatever the input is; if input is on the transistor is turned on and if it’s off the transistor is not turned on. Uh, right?
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You are right! Only thing a diode improves is that the button can not shove 5V into the thing that is connected to the input, I guess. That should usually not be a problem. What could be a problem is that if you trigger with e.g. 8V, the 5V reference will now be 8V and defeat all the protection diodes and transistor while you press the button 
Sorry, not following that…
If the input is 8 V and the button is open then JUNC is ~8 V but CLOCK_IN is still 5 V. If the button is closed then JUNC is 5 V and CLOCK_IN is still 5 V. I don’t see how anything bad happens.
It does affect the voltage on the output of the upstream module, which is bad if you’re trying to use a passive multiple. When the push button is closed the input impedance is only 1k. R1 could be made larger like 100k, then JUNC would be only half the input voltage when the push button is open but maybe that’s okay. [performs quick sim] Yeah, 100k is probably much better. Then R2 could be reduced but it’d be OK as it is, I think.
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Hmm… I though that with 8V at CLK_in_J and then a voltage divider made by R1, R2 and R3 there would be a little bit less than 8V at JUNC which would then be connected to the +5V symbol when the switch is closed and therefore everywhere where usually 5V is supposed to be. I probably got this wrong… I am not sure what happens if you connect different voltages together without any resistor or maybe R1, R2 and R3 do not make a voltage divider when there is the 5V in between R1 and R2?
No, since JUNC is connected directly to 5 V it will always (while the button’s down) be 5 V. R1 will then have a 3 V drop across it, 8 V on one side and 5 V on the other.
If there were a resistor between the 5 V rail and JUNC then the voltage at JUNC would be something different, it’d then be a voltage divider with 8 V and 5 V inputs and various resistors… but with JUNC connected directly to 5 V none of the resistors or the 8 V input matter, JUNC is 5 V.
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Thanks for explaining! I thought I had the basics down by now, but still more to learn xD
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I’ll see if I can get around to it soon. Until then, be careful 
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While we’re at it, the software needs a screensaver or a timed screen shutoff. My main one has developed quite a burn-in.
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I’ve mostly kept the screen turned off, but yeah, good idea. (And good idea too for my upcoming module with an OLED.)
(Hmm, no, flying toasters would probably take too much memory…)
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Yeah, timed shutoff is probably the way to go
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Given the hardware I’m doubtful about making the timeout settable from the panel, it’d have to be hard coded. Proposals for a value to use? Not that you couldn’t change it in the code of course.
I did not know that oleds have this problem! I have a small oled showing the energy consumption of our flat and it is running 24/7. I should think of something there too…
I was assuming hardcoded. I think a minute would be good as the default.