I divided the memory into 4 arrays, because I have to store 4 different voltages.
each in their own array.

I send two adress bytes every time, an MSB and an LSB.
BUT, the first three bits of the MSB are ALWAYS 0 !! that way, I can't get out of the memory-range.
i.e. third byte of array1=
MSB 0000 1000
LSB 0000 0011
example2: last byte of array3=
MSB 0001 1111
LSB 1111 1111

I'm quite sure that the problem is not the adressing, I display the sent adresses to an LCD every time, and they are the adresses that want to send!
it's just: If I go over 4k, the data isn't written to the 24c65
greetz,
HoD