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Must haves in GHI Boards


#1

Hello guys,
Of of the main things about open source is the ability to learn from each other and share that knowledge…
Chris at Netduino released a small description about how Netduino Go works and i see a few very important features that i would like to have on my GHI Boards.

here is the link:

what i like most is:


under Go!Sockets topic:

Hardware-wise, we've put a dual-MOSFET on every socket. This allows us to switch on and off current to every socket individually. We have lots of uses in mind for this, but three of the most important are: (1) shutting on and off modules for reflashing; (2) low-power and battery operated scenarios; (3) making sure that nothing is active during boot.


to me this is very important because as of now… for example the relay board just jitters when booting and that’s just one example…

What do you all thing…?

Jay.


#2

That consumes at least one GPIO (well, two, because you’d need to switch 3.3V and 5V for Gadgeteer?) per socket to run the MOSFET. It also increases the parts count and complexity of the mainboards. This isn’t a problem for Netduino Go! because the onboard GPIO is largely unused. On a Gadgeteer mainboard, however, the onboard GPIO is all dedicated to sockets.

While I think it’s a fine idea, it doesn’t necessarily guarantee that you wouldn’t have issues, either, because you wouldn’t necessarily need to drive anything off of the +V lines, anyway. An obvious example would be an optotriac, which could easily be driven directly from a GPIO, and could switch LOTS of current.

Startup pin state is a common issue that hardware designers have to deal with. Your relay board could/should have been designed in a way that works correctly upon startup.