Intel Edison generic calculator shield photo journal

[koendv]

My calculator 'board' is going to have the keybuttons surface mounted (along with support chips and LCD) front side, and the Edison Hirose connector and lithium bats backside. It should all fit in a case the size of the HP35s maybe slightly larger (but not much).
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How about using a Sharp Memory LCD instead of the usual two-line character LCD? Power consumption is ridiculously low (<100uW); no LED backlight needed; crisp graphics. 100% ready for battery-powered operation.

And I don't know about the Edison, but more recent kernels have support for I2C HID; maybe using something like the TCA8424 would remove any need for polling?