Dwayne Reid wrote:
> 1) It should NOT matter what happens to the data lines so long as the E
> line is LO.  Make sure that E is LO before changing anything.
>
> I *know* that the LCD ignores data while E is LO because I have 68hc11
> boards that put the LCD on the data buss - and they all worked just fine!
>
>
well, I tried that this morning. All i did was change the data lines while
E was low (confirmed on scope). The order of operation was:
        1) change data lines to input
        2) bring RW high
        3) bring E high
        4) read data DB7-DB4
        5) bring E low
        6) repeat 3-5 for reading DB3-DB0
Note that E, RS, RW are all low at the start of the operation.

The LCD remained blank, but data was sent continually back and forth.

The version that I was able to get to work omitted step 1.

I have another of the same display. I think I will wire that one up
and see if it behaves similarly.