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AR# 19569

6.2is2 ISE - Using the Verilog Language Template Code for IO buffer instantiation gives: "ERROR:HDL Compiler: 200"


Keywords: IBUF, OBUF, HDL, compiler, buffer, driver, defparam, IOstandard, Project Navigator

Urgency: Standard

General Description:
A Verilog design contains instantiation code from the Language Templates -> Verilog -> I/O Buffers and Weak Drivers ->Input or Output.

Synthesis gives the following error:
ERROR:HDLCompilers:200 - test.v line 25 Target of defparam '<pad_name>.IOSTANDARD' does not exist."


The code in the Language template includes a defparam statement for IOSTANDARD.

defparam pad_mmc.IOSTANDARD = "LVTTL";

This defparam construct is not yet supported by XST synthesis. The defparam line should be removed or commented out.

To add an IO standard, use a UCF file or use a synthesis attribute as in the example below.

//synthesis attribute IOSTANDARD of U1 is "LVDS_25"
AR# 19569
Date Created 06/17/2004
Last Updated 03/20/2006
Status Archive
Type General Article