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Pinoccio / hardware-pinoccio

The schematics, board layout, and datasheets for the Pinoccio board
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Missing pullup on the RESET pin #7

Open matthijskooijman opened 10 years ago

matthijskooijman commented 10 years ago

The RESET pin on 256rfr2 contains an internal pullup resistor. However, IIRC Atmel recommends to use an external pullup on the pin as well, especially in "noisy environments". For maximum reliability, we should probably add a pullup here in future versions.

amcjen commented 10 years ago

I remember going back and forth on this decision during the initial board design. At the time, I decided to leave it off, per the Atmel 2521 Design doc, because there are all sorts of protections one could add on there if you really want to be noise immune and safe--zener diode, ESD protection diode, a cap for noise immunity, and a series resistor for an external reset switch. Since the rest of the pins were not protected to this level, I left off this stuff as well.

Although I do think an external pull-up should work fine. We'll add it to the next revision.

matthijskooijman commented 10 years ago

Right, now I remember that document as well. Note I'm not really sure if it's really needed or worth the extra cost /effort etc, but it wouldn't hurt of course.

amcjen commented 9 years ago

Referred to in #6