how can I convert on HDF file from HWS file?

[EdHopkins]

Yes ... what we are trying to identify, is whether there is an explicit triggering mechanism defined or implied by the "equation" of the X axies (time axis), that will cause the NI PXIe-6555 card to ship data out at a particular rate (a real rate you can measure on a scope rather than a simulated set of data).

In other words, do I need to instruct my LabView guy to go configure the card to use a particular rate, or is that rate defined by the dataset itself?  If the data includes the actual sampling rate then we need to ensure the VCD file we are using to import to the Digital Waveform Editor contains the correct timing info (which is generated by Modelsim).

The VCD syntax stores only changes in data (Value Change Dump file) and a notion of time (like the X axis).  So right now my dataset (well this is simplified) looks like:

#0

0.

0/

#65

1.

#115

0.

1/

#165

1.

#215

0.

0/

If I use the "." signal as the clock sampling on both edges, this is translated into:

axis0 (7424, 2)
    Group size = 0
    Number of attributes = 5
        implicit? = 1
        increment = 5.0E-8
        numDigits = 57
        ref_time = 0
        start = 0.0

And an axis1 data vector of

0 1

1 0

1 1

0 0

0 1

etc.

So now the sampling rate is set to 50 nsec ... will the 6555 card send data out at this rate, or is there an additional set of configuration steps that need to be made?

Does your spec include any definition or instructions for pattern generation and acquisition trigger mechanisms?

Also, how are the channels assigned?  If I have columns of data in the HWS file, how does that map to the DIO channels 0-23 on the 6555 card, and are they configurable after importing the VCD file into HWS format?

[DFGray]

If you run the 6555 from the NI-HWS file, it should output at the appropriate rate.

Pattern generation is embedded in the data itself. Custom triggering is a device dependent, so is not part of the generic waveform in the file, but ref_position (often used for trigger position) and bookmarks are supported. These will be on an axis, if they are included.

The spec includes the ability to save device dependent settings, such as triggering information. This will show up as a "configs" group under the trace. However, I do not think this was implemented by the DWE. I could be wrong, so check your file.

[EdHopkins]

DFGray:

We are importing VCD files from Modelsim to LabView and it appeared initially that the Digital Waveform Editor was the easiest way to go.  The problem is now that our device contains more than 24 channels so we will need to use 2 of the 6555 cards.  So our LabView guy thinks we will need to have four different HWS files (one for input and one for output, for both cards).

Is there a scripting capability of the DWE, or some other method you could recommend that would automate this conversion.  The thing is that we are going to have about 500 to 1000 test cases when we are all done, and doing this by file open and clicking menu options is going to be super slow going and prone to data entry errors..

[DFGray]

I don't think the DWE has scripting capability, but you should be able to do what you want in LabVIEW itself. There is a data plugin for VCD, and an API for NI-HWS, so you should be able to write a simple converter which will take an input VCD and convert to an output NI-HWS. I have not done this, so cannot give specifics. If you run into issues, let me know and I can try to track down answers. I will also reply if I find the DWE has scripting capabilities.

[EdHopkins]

What exactly do you mean by "data plugin" and where is the documentation for it?

Thanks.

Ed

[DFGray]

My apologies; I meant to add a link. The VCD data plugin can be found here. Data plugins are a modular way to add support for more file types to LabVIEW and DIAdem. In LabVIEW, they are accessed from the File I/O » Storage/DataPlugin palette. You can search for other data plugins here.

I have confirmed that the DWE does not have batch file conversion capabilities.

[EdHopkins]

This appears to be for a separate tool (DIAdem) ... is that something that can be executed from within LabVIEW vi's?

Is there a separate cost for this tool?  Is THAT tool scriptable?

Ed

[DFGray]

Data plugins can be useed by DIAdem or LabVIEW. In LabVIEW, they are accessed using the VIs in the File I/O » Storage/DataPlugin palette.