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AR# 21158

MIG 007 - How can I change the CAS latency to 2.5 instead of 3?


Keywords: CAS, latency, 2.5, MIG, redq

The MIG documentation mentions that a CAS latency of 2.5 is supported. How do I make this change?


NOTE: The method below has not been verified in simulation or hardware.

To implement CAS latency of 2.5, it is best to move the addr and command going into the memory up by 0.5 cycles, and allow the rest of the state machine to remain the same. This is the easiest change, and it will not disturb any of the critical state machines/data read timings.

Below is a link to the files with the required changes. These files must be further verified/simulated. This ZIP file also contains a README that explains the changes in greater detail:
AR# 21158
Date Created 09/04/2007
Last Updated 04/06/2009
Status Archive
Type General Article