Important: In the UltraScale device family
(not UltraScale+), the address compare feature
is only supported if both the block RAM content and registers are not initialized to values
other than zero (default).
This attribute is a power-saving feature and enables the read address change (compare) detection circuit. When RDADDRCHANGE is TRUE and the read address and output registers are identical to the previous read cycle, and would therefore result in the same output, no block RAM access is performed to save power. This is most useful if the block RAM is permanently enabled. This feature is only available in the COMMON clock domain case.