Dumping real signals in VCD

Sajan

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Sep 19, 2003, 4:46:14 AM9/19/03

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Hi
I am dumping signals which are declared as integer and real.
But i cant find these signals in the dump file.
Can anyone tell me why this happens and how to over this.
Regards,
Sajan.

Sajan

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Sep 19, 2003, 1:11:44 PM9/19/03

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Well i forgot to mention that I am using Modelsim to do this.

s_sa...@yahoo.com (Sajan) wrote in message news:<d244d444.03091...@posting.google.com>...

Ajeetha Kumari

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Sep 20, 2003, 12:20:58 PM9/20/03

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Sajan,
Not sure if you are talking about VHDL or Verilog, either way
Modelsim can
probe real signals/variables in its waveform. When you say "VCD" how
do you create your VCD? That may be where the problem is, can you show
us how you dump VCD?

Ajeetha
http://www.noveldv.com

Sajan

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Sep 22, 2003, 4:03:44 AM9/22/03

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Hi
I am using VHDL.
I use the following commands in the modelsim commandline
interface to dump the signals.

vcd file dump.vcd
vcd add /top/* /*I assume this means dump all signals */

I can see real signals in the wlf format of Modelsim but not in the VCD format
in which am trying to dump the signals.

Thanks and Regards,
Sajan.

a...@noveldv.com (Ajeetha Kumari) wrote in message news:<8df95881.03092...@posting.google.com>...

Ajeetha Kumari

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Sep 23, 2003, 3:39:39 AM9/23/03

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Sajan,
You seem to be correct, some how the "vcd add" misses out real
signals in VHDL. Initially I tried a Verilog example, that worked fine
with vcd add command. Looks like only the VHDL part of it has some
issue.

Sorry, couldn't be of much help, perhaps contact Modelsim support? Why
do you prefer VCD against WLF?

> vcd add /top/* /*I assume this means dump all signals */
>

This adds all signals in top instance, use with -r if you want the
whole hierarchy (I guess you know that already).

Ajeetha
http://www.noveldv.com

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Sajan

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Sep 23, 2003, 10:54:48 AM9/23/03

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Hi
Thanks for the effort.
I am modeling a Digital to analog converter in VHDL and the output of
the module is expected to be a real signal which is a sinewave.
I want to see the sinewave in the waveform. Somehow modelsim wave
window does not show a smooth transition from one signal level to the
other. So I want to dump it in VCD and then open it using other
waveform viewer like signal-scan.
Well thats the basic idea.
Cheers,
Sajan.

a...@noveldv.com (Ajeetha Kumari) wrote in message news:<8df95881.03092...@posting.google.com>...

Alan Fitch

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Sep 23, 2003, 11:29:42 AM9/23/03

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"Sajan" <s_sa...@yahoo.com> wrote in message
news:d244d444.03092...@posting.google.com...

> Hi
> Thanks for the effort.
> I am modeling a Digital to analog converter in VHDL and the output
of
> the module is expected to be a real signal which is a sinewave.
> I want to see the sinewave in the waveform. Somehow modelsim wave
> window does not show a smooth transition from one signal level to
the
> other.

Have you tried selecting "analog interpolated" in Modelsim?

regards

Alan

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Sajan

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Sep 24, 2003, 7:49:19 AM9/24/03

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Thanks , I didnt know about that option.
Am able to get what I need using interpolated option.

Regards,
Sajan.

"Alan Fitch" <alan....@doulos.com> wrote in message news:<bkpot6$ih7$1$8300...@news.demon.co.uk>...