When I simulate a DCM in 6.1i, one of the following errors might occur:
"# ** Fatal: (SIGFPE) Floating point exception.
# Time: 140 ns Iteration: 4 Process: /testbench/uut/u_dcm/calculate_period_fx File: C:/XILINX/vhdl/src/unisims/unisim_VITAL.vhd
# Fatal error at C:/XILINX/vhdl/src/unisims/unisim_VITAL.vhd line 4920
# ** Fatal: (SIGFPE) Floating point exception.
# Time: 142 ns Iteration: 3 Process: /testbench/uut/u_dcm/calculate_period_fx File: C:/XILINX/vhdl/src/simprims/simprim_VITAL_mti.vhd
# Fatal error at C:/XILINX/vhdl/src/simprims/simprim_VITAL_mti.vhd line 4689"
This error occurs when the DCM is simulated in a resolution higher than 1 pico second. The DCM model requires that the simulation resolution be set to 1 pico second.
From 6.1i sp3 and above versions of ISE, the model will issue the following error before the Fatal Error occurs:
"# ** Error: Simulator Resolution Error : Simulator resolution is set to a value greater than 1 ps. In order to simulate the DCM, the simulator resolution must be set to 1ps or smaller"
NOTE: This error might also occur in other models if the resolution is set less than ps. Xilinx recommends that you set the resolution to ps since the library models are verified in that resolution.