>The memory is connected with a few counters to generate
>addresses. If I strobe the WE low and OE high, and then
>only change the adresses

I don't think you can do this and expect the data to store properly. If you
look at the timing diagrams I think you have to strobe one of either of
these two signals false while you change the address.

I am surprised that one of the chips stores the data apparently uncorrupted,
and think you are just lucky about this, but I do not know that particular
chip, so it may have a feature where it can be driven this way.

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