Hi guys. I´m using a Nano Every connected by USB to Raspberry Pi. Digital outputs and analogue output are working since months, but now I need a digital input who´s fluctuating. I´ve tried the node setting "digital input" with external resistor as pullup and pulldown and also "digital input with …

I'm confused. Node-red is running on the Raspberry Pi and this is an ARDUINO.... Ok, you said it was connected by USB. So: maybe start by showing us what the arduino is sending to you. Second: How fast is this fluctuation? And maybe more so: WHY is it fluctuating?

Oh, sorry, yes, NR is running on a Pi and Nano is connected to the Pi by USB. I'm using a microswitch between 5V and D12. When switch is closed I'm having 5V on D12. But in NR the debug node is jumping between 1 and 0. When the input is low, debug node still shows 1. The fluctuation is frequent…

Then I would suggest you look at the code on the Arduino and make sure it is working correctly. Or.... Hang on...... So is D12 being pull low? Do you have a resistor in the circuit with the micro switch? If not, you have probably fried D12 as an input.

You don't understand. Firmata is a protocol for communicating between an Arduino and the host computer, providing direct access to the IO pins. There's no code on the Arduino. The node gives to options and both are not working.

Ok, I didn't understand that bit. How about this bit: Do you have a resistor in the circuit with the micro switch? If not, you have probably fried D12 as an input.

Ok, you have TRIED 10k pull up and pull down. Here's my understanding of what you are seeing/getting: You want D12 as a digital input. Fair enough. The input signal is a high and you have used an external 10k resistor to pull down so at normal the input (D12) is low. When reading the input you…

[image] Crashy77: I´ve tried the node setting "digital input" with external resistor as pullup and pulldown and also "digital input with pullup". That is confusing. If your input signal is a HIGH then you would want it it "digital input with pulldown". AND.... If you did that, AND you conn…

Without connected switch and a pulldown resistor the debug node shows 0. With connected switch and a pulldown resistor the debug node shows 0. With closed switch the value is fluctuating between 0 and 1. I don't know the firmware code, but I think by choosing the options in that node you're telli…

Then I would have a serious look at the switch. (With an oscilloscope even) Better idea: Get the micro switch, resistor and LED. +5v, resistor, LED, micro switch, - At normal the LED should be off. Press micro switch. LED ON - SOLID. If it blinks, you know where the problem is. UPDATE - an…

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Arduino Nano Every with Firmata

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Crashy77 2 September 2023 22:47 7

I've tried 10k as pullup and pulldown, still fluctuations.

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Arduino Nano Every with Firmata

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