Verilog error : Unable to bind parameter in module

Question

I'm new to Verilog, I'd really appreciate it if someone could help me figure this error out:

I'm trying to write a test bench PU_tb, which is instantiating this module:

PU_conv #(
.image_width         ( image_width        ),
.image_height        ( image_height       ),
.kernel_width        ( kernel_width       ),
.kernel_height       ( kernel_height      )
) convolution (
.ACLK               ( ACLK                ), //input    
.image              ( image               ), //input
.kernel             ( kernel              ), //input
.result             ( result              )  //output    
);

The module PU_conv looks like this:

module PU_conv 
#( //Parameters
parameter integer image_width   = 10,
parameter integer image_height  = 4,
parameter integer kernel_width  = 2,
parameter integer kernel_height = 2
)( //PORTS
input   wire                                   ACLK,
input   wire [0:image_width][image_height:0]   image,
input   wire [0:kernel_width][kernel_height:0] kernel,
output  reg [0:image_width][image_height:0]    result
);

I'm getting this error:

error: Unable to bind parameter 'image_height' in 'PU_tb'
error: Unable to bind parameter 'image_width' in 'PU_tb'
error: Unable to bind parameter 'kernel_height' in 'PU_tb'
error: Unable to bind parameter 'kernel_width' in 'PU_tb'

The kernel and image widths and heights are declared as follows:

reg[5:0] param_kw;
reg[5:0] param_kh;
reg[5:0] param_iw;
reg[5:0] param_ih; ....

integer kernel_width, kernel_height, image_width, image_height;
always @(param_kw)
    kernel_width = param_kw;
always @(param_kh)
    kernel_height = param_kh;
always @(param_iw)
    image_width = param_iw;
always @(param_ih)
    image_height = param_ih;

What am I doing wrong?

sharvil111 sharvil111 · Accepted Answer · 2016-07-04T07:23:01

The following code works fine. Make sure you have declared parameters correctly in top/tb module.

module PU_conv 
#( //Parameters
parameter integer image_width   = 10,
parameter integer image_height  = 4,
parameter integer kernel_width  = 2,
parameter integer kernel_height = 2
) ( //PORTS
input   wire                                   ACLK,
input   wire [0:image_width][image_height:0]   image,
input   wire [0:kernel_width][kernel_height:0] kernel,
output  reg [0:image_width][image_height:0]    result
);

initial
begin
$display("image_width = %0d image_height = %0d",image_width,image_height);
$display("kernel_width = %0d kernel_height = %0d",kernel_width,kernel_height);
end
endmodule 

module top();

parameter integer image_width   = 8;
parameter integer image_height  = 7;
parameter integer kernel_width  = 6;
parameter integer kernel_height = 5;

wire                                   ACLK;
wire [0:image_width][image_height:0]   image;
wire [0:kernel_width][kernel_height:0] kernel;
reg [0:image_width][image_height:0]    result;

PU_conv #(
.image_width         ( image_width        ),
.image_height        ( image_height       ),
.kernel_width        ( kernel_width       ),
.kernel_height       ( kernel_height      )
) convolution (
.ACLK               ( ACLK                ), //input    
.image              ( image               ), //input
.kernel             ( kernel              ), //input
.result             ( result              )  //output    
);
endmodule

Multi dimensional arrays as inputs are supported in SystemVerilog only. Following is the output display:

// Overridden parameters
image_width = 8 image_height = 7
kernel_width = 6 kernel_height = 5

Similar question is posted in Verilog Parameter over ridding.

Verilog error : Unable to bind parameter in module

1 Answers