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AR# 13431

4.2i NGDAnno - Minimum clock period details for the PPC405 for back-annotated timing simulation


Keywords: minimum clock period, timing simulation, PPC, 405, CPMC405CLOCK

Urgency: Standard

General Description:
The minimum period timing check used in timing simulation for the CPMC405CLOCK pin is specified as 3.233ns. This is the minimum period when "operand forwarding" is being utilized.

When "operand forwarding" is not utilized, the minimum period should be set to 2.757ns. Currently, the minimum period is not based upon the "operand forwarding", but is hard-coded to 3.233ns.

If the CPMC405CLOCK clock operates faster than the minimum period in timing simulation, errors will be generated, as the minimum period for the CPMC405CLOCK will be violated.


The user must guarantee that the minimum clock period specification is not violated.

In the future, the minimum clock period for the PPC405 core will be dependent upon the operand forwarding mode (OPFWD). This mode can be configured dynamically through the TIEC405DISOPERANDFWD pin.
AR# 13431
Date Created 12/24/2001
Last Updated 04/23/2007
Status Archive
Type General Article