Arduino UNO R3 - How to use the reset pin? SOLVED

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This sounds like a simple question which should have a simple answer - but when I google it I get lots of "information" - some of which is contradictory. NB This is a general question - I feel if I put a complete project with code, diagrams etc. I'll simply confuse the issue.

So here goes - I will have the Arduino controlling bits and pieces (as you do) and it will be hidden away in a box, with some of its inputs and outputs leading to a control board.

Somewhere on the control board I intend to have a reset button which I guess I would - somehow - connect to the Reset pin.

The UNO specifications says "Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields which block the one on the board."

So the question is - how, exactly, do I use it?

Do I simply run a wire from the 5v power pin (or indeed any other 5v source) on the UNO to the switch (which would open the circuit when pressed), and a lead back from the switch to the reset pin - is it that simple?

Do I need any code in the Startup? (Seems an odd question, but this almost looks like a hardware reset alternative to the reset button which suggest no coding need - or does it!)

Or would it be better to send a "High" from one of the output pins direct to the Reset pin, with my switch triggering a bit of code which sends the output pin low? (This approach seems to get some criticism as being unsafe/undesirable in many of the articles I've found).

Thank you for clarifying - Richard

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IF you use a real Arduino board, RESETR will be on one of the header pins. The board will have the button (normally open) & the required pull-up resistor. Just take a wire from the RESET pin and a wire from GND, the ground (common.)
Use a pushbutton also normally open and thee two leads. Now, the external button works like the one on the board - no code.

Ray

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Thanks Ray, just tried it out and it worked a treat! Replicates the Reset button exactly.
I guess I could use technique this to bring any pin to LOW externally.
Cheers - Richard

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I guess I could use technique this to bring any pin to LOW externally.

Yes, but ...

You need to be sure that the pin in question is configured as an input and has a pullup resistor. Easiest way is to enable the internal pullup resistor.

This would do both for (as an example) digital pin 7:

pinMode(7, INPUT_PULLUP);