When using ISE 9.1i, I cannot find the Block Memory Generator v2.3 or v2.2 in the CORE Generator. The only one available is v2.1. Why?
With ISE8.2i, following cores were available:
Block Memory Generator v2.3 was released in IP Update #3; however, it did not make it into ISE9.1i release.
Block Memory Generator v2.2 was released in IP Update #2, but it had major problem so it was taken out of ISE9.1i release.
Block Memory Generator v2.1 is still in ISE9.1i, and it is usable with ISE9.1i, but with following drawbacks:
- Spartan-3A, Spartan-3 XA, Spartan-3E XA, and Virtex-4 XA device support not available
- Virtex-5 Simple Dual Port Block RAM primitives not available
- Minimum depth has been reduced from 8 to 2 for all architectures (not done)
- CR 223085: Behavioral models do not flag collisions for asymmetric read-write ports
Block Memory Generator v2.4 will be released with first IP Update for ISE9.1i (expected in February 2007). This version will re-introduce above features and a new ECC support.
If you can use Block Memory Generator v2.1, then feel free to upgrade to ISE9.1i. Otherwise, it is recommended that you use ISE8.2i with IP Update #3, and use the Block Memory Generator v2.3 Core until the first IP Update for ISE 9.1i is available with Block Memory Generator v2.4.
If you already have Block Memory Generator v2.3 files generated, then the files can be ported over to ISE9.1i design.