Jinx wrote...

>Well, I'll defer to your investigations. Personally I think I'd
>keep the two functions separate and use either a shift
>register for the LCD to free up more lines for the k/b, or
>use k/b decoding h/w to free up more lines for the LCD.

That's what I concluded, too.  I ended up using a 74HC138 3-to-8 decoder
to generate my strobe lines (in my case, I needed six of them); they're
pretty cheap parts, about US$0.35 in hundreds.

>The other alternative would be to keep RS R/W and E
>entirely separate from any k/b lines. There will be many
>ways to accomplish this using h/w and s/w permutations

The only one which is critical is E.  RS and R/W can flail away with
reckless abandon all day long, so long is E isn't strobed.

Dave

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