[Solved]Turning Nano on/off using Arduino

Hello,

I want to know if is possible to wire the GND pin of the NANO to the GND pin of The Arduino Uno, and the 5V (VIN) of the NANO to pin 5 of the Uno and use an LED Write HIGH or LOW code to send power to the NANO to turn it on or off.

This will allow me to have the Arduino Nano run its own program and control it's own stuff and use the Arduino Uno as a central hub that turns everything on/off.

(Yes, I understand I can use relay's but I'm saving my relays for high voltage stuff, like a fan or 120v lamp).

Thanks in advance.

Check Your text for mistakes. Which Arduino is doing what?
Check the current draw of the On/Off switched Arduino and the current capacity of the "master".

The Arduino Uno is turning on/off the Arduino Nano.

The Arduino Nano will be running a neopixel ring using the the Strandtest code, and the Arduino Uno will have a MOVI shield attached to it.

The reason why I want the neopixel code sperate (on the nano) is because when I combine the two codes together (the MOVI code and the Neopixel code, I don't get a response form my MOVI shield. I described this issue in this post here: Link to my Post). So by having the Arduino activate the nano buy coding it to activate like an LED (DigitalWrite HIGH or LOW) I can turn the nano on/off, run the neopixel and get a response from the MOVI shield. (In theory).

Sorry but the link to the old topic doesn't work.
What was the result of the previous topic? The first attempt would be ideal.

I don't think that the 20 mA of an UNÒ output will be enough to power a Nano. Check that! Else a 5 volt relay could be an option to power th Nano.

This is the link to the old topic (I don't know if this still works or not)

I guess I'll try a 5v relay. And to be sure, the Ardunio can trigger the relay (Using Write HIGH and LOW Commands) to activate the Nano correct? So I can have the Nano activated or deactivated anytime via the Arduino Nano, correct.

My end goal here is to make my own A.I system via the Arduino MOVI shield, and in order to reduce the length of code on the MOVI shield (that is attached to an Arduino Uno or Mega) I would like to have it activate separate Ardunio systems (mostly Nano's that each control Lights, or mini Robot arms) so it's easier for the MOVI shield to handle.

If relays are the best way to go then I will invest relays into my project to activate and deactivate the Arduino Nano systems via the Arduino Uno/Mega and MOVI Shield.

Thanks in advance.

"the 5V (VIN) of the NANO to pin 5 of the Uno"

First, you'd want the the Uno pin 5 to go to 5V on te Nano, not Vin - using Vin will put the pin 5 output thru the voltage regular, which won't result in a good 5V at the Nano's 328P chip.

Second, an IO pin can only source 40mA of current Absolute Mx before you risk damaging it.
The output is only guaranteed to be at least 4.2V at up to 20mA of load (due to the Rds of the output transistor between Vcc and the pin) and drops off after that.

So you might get away with powering the Nano and maybe its power LED, but that's about it before the IO pin blows.

Do it the right way and get a low Rds, logic-level, P-channel to use as an on-off switch for the Nano 5V line.
NDP6020 would be good.
Connect the Gate to the 5V supply with a 10K resistor, and pull the gate low with the Uno IO pin to turn it on.
https://www.digikey.com/en/products/detail/on-semiconductor/NDP6020P/1055922

To me it looks like You run 2 threads at the same time. That's almost violating the rules here, double posting. Why not follow up the tips given in the first topic?

To me it looks like You run 2 threads at the same time. That's almost violating the rules here, double posting. Why not follow up the tips given in the first topic?

I will use the millis idea from the first topic but this idea flew into my mind and I was just curious to see if it was possible or not.
Also as I mentioned before

My end goal here is to make my own A.I system via the Arduino MOVI shield, and in order to reduce the length of code on the MOVI shield (that is attached to an Arduino Uno or Mega) I would like to have it activate separate Ardunio systems (mostly Nano's that each control Lights, or mini Robot arms) so it's easier for the MOVI shield to handle.

I would like to ease the length of the code since the MOVI shield will be controlling a lot, I realize now that it will make more sense to use relays that way I won't have one gigantic long code to keep track of and have more room on the MOVI shield for more commands since I'll be breaking everything up into the Arduino Nano's.

Why not finish the first topic first? Why make helpers deal with 2 versions of the same issue? That’s waisting helpers time.

The first topic was a question about the code and this topic is about turning on/off an Arduino Nano with an Uno. Yes, these two posts are related to the same project, but they ask different questions.

But this topic's question has been solved (thanks by the way) and the other topic I have yet to confirm that it works (I'm working on it)

How about using the Arduino UNO WiFi to host the MOVI shield, then the Uno can publish MQTT commands just like real IOT systems.

What is the Nano doing? If it's just using one or two data pins, you could use the ESP8266-01 module which incorporates CE (Chip Enable) which you can easily control through the Arduino data pin.

Is there a schematic for the MOVI? What Arduino pins is it using?