Answers Database PPR 5.2: Defining point-to-point timespecs in cst file Record #409 Product Family: Software Product Line: XACT FPGA Product Part: ppr Product Version: 5.2 Problem Title: PPR 5.2: Defining point-to-point timespecs in cst file Problem Description: Solution 1: It is possible to define point to point timespecs in a constraint file for PPR 5.0. Here is an example: in1 out1 |ipad>-------|ibuf>-----+-----{comb logic}-----|obuf>--------<opad| | | ____ q1 _____ q2 out2 +--|DFF |------{logic}----|DFF |------|obuf>----<opad| ---- ----- Constraint file: timegrp="ned=pads(in1)"; # assign TNM of ned to ipad driving in1 timegrp="fred=pads(out1)"; # assign TNM of fred to opad loading out1 timegrp="ted=pads(out2)"; # assign TNM of ted to opad loading out2 timegrp="jon=ffs(q1)"; # assign TNM of jon to DFF driving q1 timegrp="don=ffs(q2)"; # assign TNM of don to DFF driving q2 timespec="TS01=FROM:ned:TO:fred=25"; # define p2p of 25ns timespec="TS02=FROM:ned:TO:jon=15"; # define p2s of 15ns timespec="TS03=FROM:jon:TO:don=30"; # define c2s of 30ns timespec="TS04=FROM:don:TO:ted=10"; # define c2p of 10ns End of Record #409 - Last Modified: 11/15/96 18:57

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