Answers Database


2.1i: Timing: How is the Setup/Hold Times calculated for the Datasheet IO Report?


Record #4823

Product Family: Software

Product Line: Merged Core

Product Part: Floorplanner

Product Version: 2.1i

Problem Title:

2.1i: Timing: How is the Setup/Hold Times calculated for the Datasheet IO Report?


Problem Description:
Urgency: Standard

General Description:
How is the Setup/Hold Values calculated for the
Datasheet IO Report?


Solution 1:

Setup Times
The external setup time is defined as the setup time
of DATAPAD within IOB relative to CLKPAD within
CLKIOB.   When a guaranteed external setup time
exists in the speed files for a particular DATAPAD
and the CLKPAD pair and configuration, this
number will be utilized in timing reports. When no
guaranteed external setup time exists in the speed
files for a particular DATAPAD and CLKPAD pair,
the external setup time will be reported as the
maximum path delay from DATAPAD to the IFD
plus the maximum IFD setup time, less the
minimum of maximum path delay(s) from the CLKPAD
to the IFD.



Solution 2:

Hold Times
The external hold time is defined as the hold time
of DATAPAD within IOB relative to CLKPAD within
CLKIOB. When a guaranteed external hold time
exists in the speed files for a particular DATAPAD
and the CLKPAD pair and configuration, this
number will be utilized in timing reports. When
no guaranteed external hold time exists in the
speed files for a particular DATAPAD
and CLKPAD pair, the external hold time will be
reported as the maximum path delay from CLKPAD
to the IFD plus the maximum IFD hold time, less
the minimum of maximum path delay(s) from the
DATAPAD to the IFD.




End of Record #4823 - Last Modified: 11/19/99 07:12

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