> It is possible to give up the 74HC251 and achieve almost the
> same result (each strobe pin reads six keys instead of eight).

That's very true Isaac. However I do need 8 for this project (it
may even go to 10, luckily a couple of I/O is still available). For
another project I'll need at least 15, so will add a second 74HC251.
They're left over from a short run and I was just doodling, basically
looking for an excuse to use them. The page was put up as an
example of I/O expansion and possibly a discussion point

> Normally all the strobes are at high-impedance (it is good to
> pull them up with a high value resistor)

The LCD's internal pull-ups might be enough for that


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