Hi all, I like to control a server PSU and the pinout to detect the status is about 3.1V. As I am running out of analog inputs I like to use a digital input to detect high and low with my 5V Arduino Every. I read mostly it should work even with 3.3V but it seems that the arduino is jumping around l…

Simplest solution: use a 3.3V Arduino to avoid level shifting circuitry with each input.

DrDiettrich: Simplest solution: use a 3.3V Arduino to avoid level shifting circuitry with each input. ...but then, what about the 1.5V low?

I would get problems with the board which is still finished. And a pin compatible nano 33 would not have enough power to supply the LCD with the internal converter. Also a internal pull-up to 5V will bring problems for the input 3.3V line. I am thinking about buying a bidirectional level shifter bo…

nilsro: I am thinking about buying a bidirectional level shifter board for 2€ at EBay. As it is a simple PSU is on/off status it should be fine in my opinion. What do you think? It is a single pin only. What about the issue I raised in reply #4?

The attachement has gone invisable on my screen...

The eBay board I can simply attach to the wires or somehow. That’s all, it would be simple to add if nothing is against it. Attached now the documentation of the bus. Blocks the file name before. Perhaps you see something helpful or another way... Cheers, Nils [IMG_0076.jpg]

Use INPUT_PULLUP on the pin and connect a diode with cathode to your input source - whatever that is as you have not explained it - and anode to the Arduino pin. This will increase the voltage seen on the pin by 0.6 V in either state. It will also protect the Arduino from odd voltages. :sunglasses: …

And you certainly should not be using interrupts! :roll_eyes:

nilsro: Attached now the documentation of the bus. Right. Use a comparator.

Digital Input with 3.1V - constanly changing and triggering interrupt

Projects General Guidance

Paul_B March 10, 2020, 10:05pm 11

Expand!
OK, so that is seriously mixed up!

Try the diode.

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Digital Input with 3.1V - constanly changing and triggering interrupt

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