So, any address received on AXI side greater than 255 will be see its
MSB truncated.

So, 256 will be 0, etc

When address width is lower than 32 bits (set with generic
C_DATA_WIDTH):
The address transferred from AXI interface to registers bank is
truncated.
The AXI interface will remove MSB so the address received on AXI side
could correspond to an internal register of registers bank