is possible to add a ext wifi reset button

Hardware Arduino Yún
#1

I like to put my yun in a project case
and reset the wifi - network setting to join new network
is there a pin to add an external reset button?

thanks

#2

balam:
I like to put my yun in a project case
and reset the wifi - network setting to join new network
is there a pin to add an external reset button?

Unfortunately, no.

But at least, the WiFi Reset button is located at the edge of the board, so if you place this edge of the board directly at one side of your case and drill a small hole through this side at the right position, you can trigger the WiFi Reset button with a paperclip etc. That’s how I did it; this also prevents triggering the WiFi Reset button by chance.

The situation is worse for the Linux Reset button, as it is not located at an edge of the board, so the above solution won’t work. I soldered a wire from one pin of the on-board switch to the unused pin beside IOREF:

This is something that really should be fixed in a second revision of the Yún hardware.

Uli

#3

Why not simply add a push button that takes the power of the yun.
In current configuration there is little sense to resetting the linux without the leonardo so removing power for a short while seems a good solution to me to reset both in one go.

Best regards
Jantje

#4

Jantje:
Why not simply add a push button that takes the power of the yun.
In current configuration there is little sense to resetting the linux without the leonardo so removing power for a short while seems a good solution to me to reset both in one go.

I wanted a clean solution that doesn’t produce problems later on of which I wasn’t aware now.

Why is there a Reset button on the board in the first place? Is it a good idea to reboot a Unix by removing power? Can’t the Leonardo do useful things (e.g. continue to collect data) while the Linux part is rebooting? Etc. …

#5

uli_:
Why is there a Reset button on the board in the first place? Is it a good idea to reboot a Unix by removing power? Can’t the Leonardo do useful things (e.g. continue to collect data) while the Linux part is rebooting? Etc. …

  1. Adding a physical way for resetting allows the non-geek (or less-geek) to take back control of the board in case of problems.
  2. With the Yun as it comes out of the box, yes, there are NO issues in just removing power.
  3. Technically yes (the two processors run independently) but you cannot collect much data on the leonardo: ram is the issue
#6

uli_:
Why is there a Reset button on the board in the first place? Is it a good idea to reboot a Unix by removing power? Can’t the Leonardo do useful things (e.g. continue to collect data) while the Linux part is rebooting? Etc. …

my 2 cent
Personally -if I had to decide- the next revision of yun would have 1 reset button. That button would reset Linux and Leonardo.
Basically you have 2 processors on one board. When you use the board I think it is safe to assume that you want them to talk to each other. Having to cater for taking down 1 while the other is still talking is pretty hard. It is probably feasible on the Linux part but the leonardo only has 32K - 4K bootloader -2K bridge -2k for String ........
In my view it is just so much easier and with very little drawbacks to simply reset Leonardo than to cope with the problem "what was the last thing you heard?"
So from a coding point of view I would prefer Leonardo to reset together with the Linux. And I'm not the only one. (Someone proposed to add reset-mcu to the boot script of Linux.)

The only drawback I see of only having 1 reset button is that the boot process of Linux is much longer than that of Leonardo. But does that matter?
I see 2 different situations: development and production. In production you consider pressing the reset button when "something is wrong" and you want it to work again. It is "one service" not working, so you want to reset button for the "service" and both processors reboot.
In development it is likely you want to reset arduino without linux. (note this is currently not 100% safe) But will you be pressing the reset button on the board in that case?
Why not use the reset button in the serial monitor? (does the reset button in the serial monitor work for yun over wifi?)
Why not run the reset-mcu command?
Or upload a sketch? (I think this is safest)

Best regards
Jantje

#7

Jantje:
Personally -if I had to decide- the next revision of yun would have 1 reset button.

What about this scenario:

The Leonardo runs as a pulse counter, and it's important to not miss any pulses. It stores the pulse count in one variable.

The Linux part retrieves the pulse count from the Leonardo from time to time (to transmit it via the net, or whatever) and then resets it to zero on the Leonardo.

In this scenario, it’s no problem if the Linux part has to reboot for some reason as long as the Leonardo keeps running.

This scenario would argue strongly against only a common reset button. Or do I overlook something?

#8

Yep, of course. But this would also be true for a common Reset button, as suggested by Jantje. More precisely, I should have said: “Why is there a separate Linux Reset button on the board in the first place?”

  1. With the Yun as it comes out of the box, yes, there are NO issues in just removing power.

Ah, good to know.

  1. Technically yes (the two processors run independently) but you cannot collect much data on the leonardo: ram is the issue

My pulse counter example from my posting before this one would be an example where the limited RAM isn’t an issue.

#9

uli_:
Why is there a separate Linux Reset button on the board in the first place?

I would say, "why not?". Arduino users are already used to have a dedicated reset button for the only processor (the MCU) on the board. Making a board with two of them means having two buttons. IMHO at least. I'm not into some design decisions. I'm the geek, not the UX expert :wink:

#10

Misunderstanding. 8) Mine was a rhethoric question that tried to point out that the second button might be there for a reason. So I’m on your side. :grin:

#11