Re: Bug in Synplify?

Andy wrote:


When you let it infer ram, are you getting LUT based rams
(combinatorial read), or block rams (registered reads)?

LUT rams cannot be reset. I seem to recall block rams on some devices
can have a reset. But the results of that reset may be deferred by the
synchronous read circuitry (depending on whether you registered the
read address, or registered the read data in the inferring code), so
implementing that same cycle-accurate behavior may take more flops
than you thought, but since you did not post how you are reading the
RAM, I cannot tell.

Andy

The Block RAM reset does not reset cells in the memory array, it just resets bits in the output register forcing the output to the reset value. The contents of the array are left unchanged.
.

Relevant Pages

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