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Old 07-10-2009, 11:47 PM
JimLewis
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Default Re: std_logic_textio library

On Jul 10, 9:30*am, Jonathan Bromley <jonathan.brom...@MYCOMPANY.com>
wrote:
> On Fri, 10 Jul 2009 08:12:27 -0700 (PDT), Shannon wrote:
> >I'm planning on using std_logic_textio library for my testbench. *I
> >just want access to the hread / hwrite functions. *I don't like doing
> >non-standard things. *Am I making a mistake?

>
> And it's officially supported in the 2008 standard.


Try turning on the VHDL-2008 switch in your simulator.
If hread and hwrite work without the package reference to
std_logic_textio, then these new features has been implemented.
It works in a couple of the simulators I have tried it.

In the 2008 standard, these functions were upgraded (now handle
parameters that are not a multiple of 4 bits for hexadecimal or
3 bits for octal) and were moved to std_logic_1164. The package
std_logic_textio still exists for backward compatibility.
It has aliases to the functions in std_logic_1164 (to allow
selected name references to the package to still work).

If your simulator does not support VHDL-2008 textio yet,
use std_logic_textio, but avoid selected name references
(such as ieee.std_logic_textio.hwrite) to the subprograms in
the package. This way when you have VHDL-2008 support, your
design will work with or without the reference to
std_logic_textio.

Cheers,
Jim

SynthWorks VHDL Training
www.SynthWorks.com



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