The output registers of the block RAM might not initialize to the proper value immediately after configuration.
In ISE Design Suite 11.5 and earlier software versions, there is an issue that affects the output registers of the block RAM.
The block RAM output registers/latches will be initialized after configuration to the Set/Reset value (SRVAL_A or SRVAL_B) instead of the intended Initialization value (INIT_A or INIT_B).
This issue will only affect a design which meets the two following criteria:
There are options for a work-around. Any of the following can be done:
This issue will be fixed in the ISE Design Suite 12.1 Software.