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AR# 19862

6.3i UniSim, Simulation - The ISERDES and OSERDES models report different messages when incorrect attributes are used


Keywords: UniSim, simulation, ModelSim, NC-VHDL, ISERDES, OSERDES, Virtex-4

Urgency: Standard

General Description:
The ISERDES and OSERDES models report different messages for the same condition. For example, when I set DATA_RATE as DDR and DATA_WIDTH = 2 for ISERDES and OSERDES, I receive the following messages:

# ** Warning: WARNING : DATA_WIDTH or DATA_RATE has illegal values.
# Time: 10 ps Iteration: 0 Instance: /oserdes_vhd_tb/uut/u1/inst_ioout

# ** Failure: Attribute Syntax Warning The attribute DATA_WIDTH on /ISERDES instance is set to 2.
# The Legal values for DDR mode are 4, 6, 8, or 10
# Time: 0 ps Iteration: 0 Process: /iserdes_vhd_tb/uut/u1/prcs_init File: unisim_VITAL.vhd
# Break at unisim_VPKG.vhd line 1328

Also, the severity levels of the messages are completely opposite.


This problem has been fixed in the latest 6.3i Service Pack available at:
The first service pack containing the fix is 6.3i Service Pack 1.
AR# 19862
Date 11/18/2008
Status Archive
Type General Article