Re: gEDA-user: problems with icarus ..

[Stephen Williams <steve@icarus.com>]

Lars Segerlund wrote:
>  I am trying to synthesice a simple adder, and I am getting errors like 
> this.
>
>  Does anybody know whats going wrong ?
>
> module addc(A, B, CIN, COUT, Q);
>     input A, B, CIN;
>     output COUT, Q;
>     assign Q=A ^ B ^ CIN;
>     assign COUT= (A & B) | (A & CIN) | (B & CIN);
> endmodule
>
> bash-2.05b$ ../tools/bin/iverilog -S addc.v
>
>  Passes
>
> bash-2.05b$ ../tools/bin/iverilog -tfpga addc.v
> UNSUPPORTED LOGIC TYPE: 19
> UNSUPPORTED LOGIC TYPE: 19
> UNSUPPORTED LOGIC TYPE: 1
> UNSUPPORTED LOGIC TYPE: 1
> UNSUPPORTED LOGIC TYPE: 1
Including the version would help. However, I can tell you
that those are AND and XOR gates that that particular code
generator doesn't support yet. Try for example -tfpga -farch=virtex
and see an improvement.

--
Steve Williams                "The woods are lovely, dark and deep.
steve at icarus.com           But I have promises to keep,
http://www.icarus.com         and lines to code before I sleep,
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