Micro/Nano Board: Why two Reset pins? Any difference?

NooB question: Why do both the Arduino Micro & Nano PCB have two Reset pins? And: Are those identical?

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Bildschirmfoto 2020-09-07 um 15.34.54.png

Wookbert:
Why do both the Arduino Mini

That's an Arduino Micro, not a Mini. Despite the similar names, they are significantly different boards, so good to keep from mixing up the two.

However, the Mini also had two reset pins!

Wookbert:
& Nano PCBs have two Reset pins?

I am also curious about this. It's not the sort of pin you're likely to need two of!

As for why both the Nano and Micro have two. If you look closely, you can see that the Micro actually has the same pinout as the Nano, only with an extra pin on each side. I believe the Nano came first, then the designer of the Micro made the sensible decision to use the established pinout.

Wookbert:
Are those identical?

Both reset pins are identical.

An external AREF pin would have been nice. >:(

I searched a little

the second reset pin was auto-reset from external TTL-Serial on boards which were the inspiration for Nano. Nano was designed by Gravitech

the origin is the BASIC Stamp board. it had a pin intended to be connected to DTR there

https://johnloomis.org/ece445/stamp/modules.htm

https://www.parallax.com/go/BASICStampConnectHelp/Content/HardwareTopics/PinDesc.htm
1 SOUT Serial Out: connects to PC serial port RX pin (DB9 pin 2 / DB25 pin 3) for programming.
2 SIN Serial In: connects to PC serial port TX pin (DB9 pin 3 / DB25 pin 2) for programming.
3 ATN Attention: connects to PC serial port DTR pin (DB9 pin 4 / DB25 pin 20) for programming.
4 VSS System ground: (same as pin 23) connects to PC serial port GND pin (DB9 pin 5 / DB25 pin 7) for programming.

1 Like

Mind to translate that using two or three sentences into housewife (or Arduino NooB) language?

Wookbert:
Mind to translate that using two or three sentences into housewife (or Arduino NooB) language?

there was a board which they copied. on that board that pins configuration made sense.

a joke:
A man asks his wife, as she prepares a strudel, why she cuts the ends short.
She answers: “My mother did so.”.
Man: “But why?”
She: “I don’t know. I ask her.”
Later she asks her mother and the mother says: “I had a short baking pan”

so I don’t know if my English oriented on tech mastered this kitchen joke, so I would like a feedback on it :slight_smile:

Juraj:
the origin is the BASIC Stamp board. it had a pin intended to be connected to DTR there