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AR# 44597

13.3 XST - "ERROR:HDLCompiler:1830 - "<*>.v" Line 5: Cannot omit port direction for function/task declarations"


Beginning with the 13.3 software, the new XST parser will generate the following error message when port directions are omitted for any of the arguments inside the function/task declaration:

"ERROR:HDLCompiler:1830 - "top.v" Line 5: Cannot omit port direction for function/task declarations
INFO - You can change the severity of this error message to warning using switch -change_error_to_warning "HDLCompiler:1830"

Here is the sample code:

module top (a, b, c);
input [3:0] a,b;
output [3:0] c;
assign c = oring(a,b);
function [3:0] oring ([3:0] a,b);
  oring = a | b;


The above error occurs when the direction of a port is not specified for any of the arguments in the function definition. In the above example code, the port direction of argument [0:3] a,b for function oring is not specified, which causes the compiler to error out with HDLCompiler:1830.

Please note that you can change this error message to a warning by using the XST switch: -change_error_to_warning "HDLCompiler:1830", as mentioned in the INFO message.
AR# 44597
Date Created 10/19/2011
Last Updated 05/26/2014
Status Archive
Type General Article
  • ISE Design Suite - 13.3