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Altera_Forum
Honored Contributor
16 years agoAltera Simple Dual Port RAM -- Read cycle latency
Hi all,
I use in my design a altsyncram, simple dual-port RAM, generated by MegaWizard. It is 4096 words deep, with 14-bit words input, with a single clock for both Port A and B. When performing a basic read access operation, I observe a 2 clocks ticks latency. By that I mean, I assert my read_enable signal, with relevant address on the address bus, and data become available 2 clock ticks after read_enable assertion. I want it to be one clock tick only. Is it possible with that type of memory? FYI, when designing the core, under the 'Regs/Clkens', I unticked the 'Read Outputs q_a/q_b'. thanks for your help on that!3 Replies
- Altera_Forum
Honored Contributor
Thanks,
the problem was in my wrapper for the altsyncram. Where the core is instantiated , I changed the "outdata_reg_a" to "UNREGISTERED" and now it works, there's only one clock cycle latency before data output is valid. Thanks again, problem solved!- Jiayi_H_Intel
Occasional Contributor
Thanks. This answer solved the same problem in my design.
- Altera_Forum
Honored Contributor
If read_enable is synchronous with the clock, when it's asserted (1st ), its registering is made at next clock (2nd) cycle.