Ambiguous reference to type `UNSIGNED' - How to deal with th

I am using

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.numeric_std.all;
use IEEE.std_logic_arith.all;
use IEEE.std_logic_textio.all;
use std.textio.all;

in a testbench, I need the CONV_STD_LOGIC function of std_logic_arith
lib and the unsigned type of the numeric_std.all (the DUT has unsigned
signal from this), but when compiling it in Aldec riviera, I met the"
Ambiguous reference to type `UNSIGNED'" error. Could anybody can give
me a clue?

 

[Martin Thompson]

zhaoxiang.99@gmail.com writes:

I am using

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.numeric_std.all;

This line is good!

use IEEE.std_logic_arith.all;

This line is bad. It is a non-standard library, which means your code
can behave differently, depending on whos library you use to compile
it with. And therefore you can have different simulation and
synthesis results.

use IEEE.std_logic_textio.all;
use std.textio.all;

in a testbench, I need the CONV_STD_LOGIC function of std_logic_arith
lib and the unsigned type of the numeric_std.all (the DUT has unsigned
signal from this), but when compiling it in Aldec riviera, I met the"
Ambiguous reference to type `UNSIGNED'" error. Could anybody can give
me a clue?

The reason for the error you are getting is that UNSIGNED is defined
in both libraries.

Use just numeric_std and change the conv_unsigned to to_unsigned.

See the VHDL FAQ for more gory details, and there's a number of
threads from the past on this subject.

<RANT>
Why is it in this day and age when numeric_std has been around
for so long that the vendors (and universties!) keep insisting on
perpetuating std_logic_arith!?

And having templates that include both std_logic_arith and
std_logic_unsigned - sometimes when neither are required!
</RANT>

Sorry, had to get that off my chest!

Cheers,

Cheers,
Martin

--
martin.j.thompson@trw.com
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.net/electronics.html

 

[Jonathan Bromley]

On 09 Jan 2007 08:54:36 +0000, Martin Thompson
<martin.j.thompson@trw.com> wrote:

RANT
[...]
/RANT

Sorry, had to get that off my chest!

Welcome to LRA (Library Ranters Anonymous). We have
regular meetings - approximately once a month - on this
newsgroup when people post the offending use clauses.

Sadly, the vendors who insist on providing
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;
in their default template aren't listening.
--
Jonathan Bromley, Consultant

DOULOS - Developing Design Know-how
VHDL * Verilog * SystemC * e * Perl * Tcl/Tk * Project Services

Doulos Ltd., 22 Market Place, Ringwood, BH24 1AW, UK
jonathan.bromley@MYCOMPANY.com
http://www.MYCOMPANY.com

The contents of this message may contain personal views which
are not the views of Doulos Ltd., unless specifically stated.

 

[Martin Thompson]

Jonathan Bromley <jonathan.bromley@MYCOMPANY.com> writes:

On 09 Jan 2007 08:54:36 +0000, Martin Thompson
martin.j.thompson@trw.com> wrote:

RANT
[...]
/RANT

Sorry, had to get that off my chest!

Welcome to LRA (Library Ranters Anonymous).

Although as our names are posted, would we be "ymous" instead ? Or
"nonymous"... My Greek never was up to much.

We have regular meetings - approximately once a month - on this
newsgroup when people post the offending use clauses.

Yes it happens rather a lot! I've been helping out a student at
work whose tutor insists he does that sort of thing as well :-(

Cheers,
Martin

--
martin.j.thompson@trw.com
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.net/electronics.html