03-22-2010 12:02 PM
I would like to find some way to speed up my behavioral simulation time for a design in EDK. I am using ModelSim SE for the simulations.
I would like to be able to use a larger timestep (maybe 100ps instead of ps), but the UNISIM library throws an error when I attempt to simulate with anything besides 1ps resolution. Here is that error message:
# ** Fatal: (SIGFPE) Floating point exception.
# Time: 0 ps Iteration: 0 Process: /system/clock_generator_0/clock_generator_0/using_
pll0/pll0_inst/pll_inst/using_pll_adv/pll_adv_inst /clock_period_update_p File: C:/Xilinx/10.1/ISE/vhdl/src/unisims/unisim_VITAL.v hd
# Fatal error in Process clock_period_update_p at C:/Xilinx/10.1/ISE/vhdl/src/unisims/unisim_VITAL.v
hd line 168422
# HDL call sequence:
# Stopped at C:/Xilinx/10.1/ISE/vhdl/src/unisims/unisim_VITAL.v
hd 168422 Process clock_period_update_p
The erroring line in unisim_VITAL.vhd is as follows:
period_vco_rm_tmp1 := period_fb_tmp / 1 ps;
I guess it may just be the nature of the beast, but a 300ms simulation takes close to 18 hours to complete on my machine. Is there any way to shorten the simulation time?
03-22-2010 01:21 PM
I am afraid that it may be the nature of the beast. At least you have ModelSim SE; I have been working with PE so
if I had the money I could buy better performance. But you don't have that option.
You can see a very slight improvement if simulate in batch mode, rather than with the GUI. But you are probably
already doing that.