Synthesizing ROM

[nezhate]

Hi all,
I've to implement a ROM, which has 11 bits for address and 8 bits data
wide. The problem is: ROM is not fully initialized. Data is read from
an external file. When synthesizing under precision, I'm getting many
warnings.
Should I initialize the whole of ROM? If yes, what is the best way to
do this (without affect data that must be contained in this ROM)?
Cheers.

 

[Edmond Coté]

On May 6, 1:22 am, nezhate <mazouz.nezh...@gmail.com> wrote:

I've to implement a ROM, which has 11 bits for address and 8 bits data
wide. The problem is: ROM is not fully initialized. Data is read from
an external file. When synthesizing under precision, I'm getting many
warnings.
Should I initialize the whole of ROM? If yes, what is the best way to
do this (without affect data that must be contained in this ROM)?

ROM synthesis with Precision RTL is easy and if it doesn't work, copy/
paste the example found in the synthesis style guide. Otherwise,
without knowing more about your problem, I can't help you.

Edmond

 

[mk]

On 5 May 2007 22:22:02 -0700, nezhate <mazouz.nezhate@gmail.com>
wrote:

Hi all,
I've to implement a ROM, which has 11 bits for address and 8 bits data
wide. The problem is: ROM is not fully initialized. Data is read from
an external file. When synthesizing under precision, I'm getting many
warnings.
Should I initialize the whole of ROM? If yes, what is the best way to
do this (without affect data that must be contained in this ROM)?
Cheers.

I think it is much better to instantiate a ROM generated with your
back-end tools. This way you are liable to get much more repeatable
results especially if you change synthesis tools and/or methodologies
at any point.

 

[nezhate]

On May 6, 11:09 pm, mk <kal*@dspia.*comdelete> wrote:

On 5 May 2007 22:22:02 -0700, nezhate <mazouz.nezh...@gmail.com
wrote:

Hi all,
I've to implement a ROM, which has 11 bits for address and 8 bits data
wide. The problem is: ROM is not fully initialized. Data is read from
an external file. When synthesizing under precision, I'm getting many
warnings.
Should I initialize the whole of ROM? If yes, what is the best way to
do this (without affect data that must be contained in this ROM)?
Cheers.

I think it is much better to instantiate a ROM generated with your
back-end tools. This way you are liable to get much more repeatable
results especially if you change synthesis tools and/or methodologies
at any point.

Hi again,
Thank's for your help, I've already resolved this problem, I had some
bad code, when I've correct it, automatically, precision has
initialized the rest of ROM with 0. Now my ROM is working!
Best Regards.