Can't import VCD file in Digital Waveform Editor

[KP_UMN]

Hi, I tried creating a VCD file from my Verilog simulations and tried to import it into the Digital Waveform Editor. (The file is in *.dmp format) The VCD Import Wizard shows the available signals, and I can select the signals that I want, and map X and Z states to 0 or 1. The 'Importing VCD File' and 'Executing...' tasks get completed as well.
However, I get the following error at the end of the 'Executing...' task : "Error-130099 Load Data"

Any idea what this means?

Thanks!
-KP

Kaustubh Patil
Medtronic, Inc
Minneapolis, MN

[Sastry V.]

Hello Kaustubh,

1. Can you try with another VCD file and see.
2. Can you attach a sample VCD file for me to try out that you are saying, gives problems?

Sincerely,
Sastry V
Applications Engineer
National Instruments

[KP_UMN]

Hi,

Sorry for the late reply. I think I figured out what the problem was. My simulation runs with a timescale 1nS, so the VCD variables need 1Giga samples per second. The DWE creates a file (DWEMount_xxxxx.temp) for the VCD import, and I saw that this file is HUGE (more than 12GB!). Pretty soon my hard disk got full, and I think that's why I got the error message that I mentioned before.
I created another simple VCD dump file, and had no problems importing it into the DWE.
So I guess the problem is that for large designs, A LOT OF MEMORY is needed. I will try to be very selective in which variables I dump.

Any idea if it is usual for the DWEMount_xxxx.temp file to be of the order of tens of GB? Any other suggestions?

Thanks,
-KP

Kaustubh Pat
il
Medtronic, Inc

[DQN]

Hello everyone
I am a new Labviewee can someone help me (give me an example) create a VI file which can read VCD file in Digital Waveform Editor. Thank you
DQN

[sergesl]

The following product allows you to import VCD format: NI Digital Waveform Editor located at http://sine.ni.com/nips/cds/view/p/lang/en/nid/13050

[Allen H]

Hi DQN,

The Digital Waveform Editor is a stand alone software program that contains a VCD importer. Once you have the VCD file in the Editor, you may save it to the HWS file format, or you may export the waveform to an ASCII or binary file. Here is a link to the Editor: http://sine.ni.com/nips/cds/view/p/lang/en/nid/13555

Will you need to generate or acquire the signals with a digital I/O device?

Allen

[Eric L]

Hello,

I am seeing a very similar issue, and I was wondering if there is a workaround, or if there are some tips on how the vcd file should be setup.  In my case it ran for several hours before running out of disk space (22 Gbytes used by the DWEMount_xxxxx file). 

For example, can you only have a certain number of signals listed?

Any restrictions on the timestep?

Thanks,

Eric

[Just_me1]

Sorry tyo dig up old Posts , but nobody answered this question which is what I'm running into.

Hello,

I am seeing a very similar issue, and I was wondering if there is a workaround, or if there are some tips on how the vcd file should be setup.  In my case it ran for several hours before running out of disk space (22 Gbytes used by the DWEMount_xxxxx file). 

For example, can you only have a certain number of signals listed?

Any restrictions on the timestep?

Thanks,

Eric

[Just_me1]

Remove the LIB directory info at the bottom of the file and it will import nicely.

[JaredW]

Hello,

The Digital Waveform Editor will import VCD files in such a way that NI-HSDIO devices can use them.  In order to exactly reproduce the edge placements in a VCD simulation pattern on an NI-HSDIO device, the DWE may have to create multiple data samples for a VCD timing period, then use a faster clock rate when generating that pattern.  For example, if you have a VCD file thas has a clock signal that toggles every 10ns, and all of the other signals in the VCD file have edge transitions aligned with this clock (transistion at 10ns intervals), then the DWE only needs to import 1 sample for each 10ns period and will require a device frequency of 100MHz.  However, if your VCD file has a signal that contains even one edge transition that is 1ns off of the clock signal, the DWE will have to import 10 samples for each 10ns period in order to exactly reproduce this timing, and will require a device frequency of 1GHz.

If your VCD file has very accurate edge placements (some simulations place edges with pico or even femto second precision), the VCD importer may have to oversample the data to the point that the resulting file is extremly large, or could require a device generation frequency that is unrealistic.

For DWE 1.0.1, the best solution will be to make sure that all exported VCD signals have their edge transitions occuring exactly in line with the simulation's master clock, or atleast aren't exported with femto and pico second edge placement accuracy. You should also only export to the VCD file the signals you intent to import into the DWE (even leave out the clock signals if they aren't used).

NI is working on another version of the DWE that will address some of these oversampling issues for VCD importing.  This solution should be available within the next few months. If this issue is a showstopper for you, email NI at hsdiobeta@ni.com

Jared W.

Software Engineer - National Instruments

Message Edited by JaredW on 01-11-2006 02:52 PM

Message Edited by JaredW on 01-11-2006 02:53 PM