[Solved] Arduino Issue on Zalophus

Its been a long time since I've used the Uno and never your new version... but doesn't it have a Vin pin for input of voltage?

https://store-usa.arduino.cc/products/arduino-uno-rev3 shows a Vin that is for input and the 5V is for output.

@inq 

1) For what I've heard, the 5V pin can be used as either an output or an input.

I've used it as an input before and it did work.

2)I've tried using the Vin pin instead, the result is the same.

Also, the Vin pin only accepts voltages from 6V (better if at least 7V).

@valerio

Posted by: @valerio

@inq 

1) For what I've heard, the 5V pin can be used as either an output or an input.

I've used it as an input before and it did work.

2)I've tried using the Vin pin instead, the result is the same.

Also, the Vin pin only accepts voltages from 6V (better if at least 7V).

Maybe this might help:

From: arduino-uno-rev3

Cheers

@frogandtoad 

That's why I was using the 5v pin instead.

I've tried on another board, there is the same issue.

@valerio

Posted by: @valerio

@frogandtoad 

That's why I was using the 5v pin instead.

I've tried on another board, there is the same issue.

I must be missing something, because you said that you were providing "four 1.2v AA batteries" - Does that satisfy the voltage requirements?

Cheers

@frogandtoad 

Four times 1.2v is 4.8v, and my teachers at school told me an Arduino

has a 10% tolerance.

90% of 5v is 4.5v, so 4.8v is enough.

Have a nice day

@valerio

Posted by: @valerio

@frogandtoad 

Four times 1.2v is 4.8v, and my teachers at school told me an Arduino

has a 10% tolerance.

90% of 5v is 4.5v, so 4.8v is enough.

Have a nice day

Thank you so much for your appreciation of the time I took to research for you... you certainly know more than the information I presented to you... go forth and learn!

Cheers

@valerio Did you miss where @frogandtoad posted the UNO doc that had this about the 5V pin? 

@frogandtoad @Inq Gentlemen, he 'heard' that the 5V pin can be used. He also stated in the OP that he did not have continuity between 5V and Grd, and thought that was wrong! I know I don't have the benefit of his education (he is in school) and not sure about my two mature friends so perhaps electricity works different now and we old guys are just too old to understand the modern way. I know @frogandtoad posted some documentation that pointed out his problem, but who knows if it is valid, it could be fake docs.

@zander 

If the voltage is 4.8v, I don't see why it should be a problem to bypass the regulator, since 4.8v is close enough to 5v to work anyway.

Regardless of the continuity, if i plug the supply cables into the board it does not work.

During the four-legged robot I used the same kind of supply on a Nano and it worked without issues.

I don't get what's wrong with doing this.

Have a nice day

@valerio It's wrong because that's what the documentation says. 

@zander

Yes, the board operates from 6v onward, but that's only on the Vin pin.

I used the 5v pin, which can be supplied with 5 volts.

The only way this may not work according to the documentation would be if the voltage from the batteries

went over 4.8v and damaged the board.

But I tried to supply the board from the pc via a usb cable, and it could turn onm so that's not broken.

I've read the documentation more carefully, and I still can't see where's the issue.

@valerio The issue is that the doc says the DC barrel jack, the USB, the Vin are all and only input voltage sources recommended and the non-USB power can be from 6V to 20V but it probably will not work if provided with less than 7 (NON USB only).

The 3 paragraphs that talk about input power never say the 5V pin is an input, moreover the ONLY reference to it is as an explicit output pin. It goes on to say the board can be damaged if power is applied to either the 5V or 3.3V pins.

Will some boards work with 5V supplied to the 5V pin, probably, but it is NOT recommended by the thousands of engineer hours that built the board. 

We don't know if your board is genuine or a clone, if it's a clone, then all bets are off.

A Nano is not a UNO. Different board, different rules.

If your board isn't working with 4.8V (at best) on the 5V pin, use the Vin, USB, or DC jack and move on.