Hi Only that the first address lines that are used for refresh need to be grouped. As example for a 128 cycle refresh, that would be that one could mix any of the A0-A6 lines. This is because of how the blocks of RAM are accessed and then selected by a mux to the output. If you took a 128 cycle refresh and swapped A0 with A7, only half the arrays would get refresh. It still might not be an issue, depending on software and other hardware. One can do refresh by just reading the array, such as a DMA for video out might do. Dwight