gistfile1.txt

In READ_FIRST mode only, the dual-port block RAM has the additional restriction
that addresses for port A and B cannot collide. This applies for both TDP and SDP
modes. A read/write on one port and a write operation from the other port at these
shared addresses have the following restrictions:
• When both RAMB16BWER ports are 18 bits wide or smaller: A13–A6, including
A4, cannot be the same.
• When any one RAMB16BWER port is 36 bits wide: A13–A7, including A5, cannot
be the same.
• In all RAMB8BWER port width configurations: A12–A6 including A4 cannot be
the same.
If these address restrictions are ignored, the operation of the block RAM is not
guaranteed and could result in the corruption of the memory cell. The enable pins
(EN) can be used to avoid simultaneous access. WRITE_FIRST mode does not have
these restrictions.