Advance Place and Route Options (3)
How many passes should be run? Here are a few estimates based on family:
- 3K, 5K, and smaller 4KE/XL devices ----------- 15+ passes
- Mid-range 4000E/4000XL devices ----------- 8 -12 passes
- XC4028EX/XL and XC4036EX/XL ----------- 3-6 passes
- XL devices > XC4036 ----------- ɛ passes
Guidelines are based on length of time to run passes
- Guidelines above assume a run time of ~10 hours on a SPARC 10 workstation
Other factors which effect runtime:
- Loose timespecs decrease runtime of each pass
- As percent of device used by design increases, run time increases
- Larger devices will take longer to place and route