Xilinx ISE 6.1i DCM is dead

Sep 17, 2003 1 Replies

The 6.1i/6.1i SP1 unisim DCM model doesn't work in a simulation that works with the model included in 5.2i SP3. Has anyone else experience the same problem? What has been changed? Why is the model changed?



/Patrik Eriksson



"Patrik Eriksson" a écrit dans le message de news: snipped-for-privacy@netinsight.net...

Unisim DCM model is change and now the RST signal must be asserted for 3 CLKIN clock cycles. A test exists in VITAL model to print a message if the timing is not correct but the test doesn't work at "power up" because a signal is not correctly initialized.

To make this working, do the folowing modifications.

in "unisim_VITAL.vhd" and "simprim_VITAL_mti.vhd" files replace all occurences of the folowing line signal rst_reg : std_logic_vector(2 downto 0); by : signal rst_reg : std_logic_vector(2 downto 0) := "000"; and compile the modified files.

Now the simulation must generate an error like: # ** Error: Timing Violation Error : RST on instance * must be asserted for

3 CLKIN clock cycles. # Time: 30 ns Iteration: 3 Instance: /testbench/u_2/dcm_i

Gerard Thierry

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