Daqarta
Data AcQuisition And Real-Time Analysis
Scope - Spectrum - Spectrogram - Signal Generator
Software for Windows
Science with your Sound Card!
The following is from the Daqarta Help system:

Features:

Oscilloscope

Spectrum Analyzer

Signal Generator
(Absolutely FREE!)

Spectrogram

Pitch Tracker

Pitch-to-MIDI

DaqMusic
(Free Music... Forever!)

Remote Operation

DC Measurements

True RMS Voltmeter

Sound Level Meter

Frequency Counter
    Period
    Event
    Spectral Event

    Temperature
    Pressure
    MHz Frequencies

Data Logger

Waveform Averager

Histogram

Post-Stimulus Time
Histogram (PSTH)

Macro System

Multi-Trace Arrays

Trigger Controls

Auto-Calibration

Spectral Peak Track

Spectrum Limit Testing

Direct-to-Disk Recording

Accessibility

Applications:

Frequency response

Distortion measurement

Speech and music

Microphone calibration

Loudspeaker test

Musical instrument tuning

Animal sound

Evoked potentials

Rotating machinery

Automotive

Product test

Contact us about
your application!

Arb Files 0-7

Controls: Gen Dlg >> Stream >> Wave >> Arb >> 0-7
Macros : Arb0-Arb7, ArbX0-ArbX7

By default, the 8 Arb file locations show as simply Arb 0 through Arb 7 when Arb files are not loaded. To load a file to a particular location, click on that button. A standard Windows Open dialog will open to allow you to select a file.

Arb files are assumed to reside in Daqarta's own User_Data directory. See the Open Existing Data File topic for tips on opening files in other directories, as well as copying, moving, or deleting files.

Arb files may hold 1024, 2048, 4096, or 8192 samples. If you load a file of some other size, it will be truncated to the largest that will fit. Files shorter than 1024 samples are not accepted.

An Arb file is assumed to hold exactly one cycle of an arbitrary waveform. If it contains instead a higher integer number of cycles the overall operation will be the same, but the Freq and Phase controls will be off by that same factor since a single cycle is assumed. Even more important, the resolution is reduced needlessly since there are less points per actual cycle at the output.

Files may be either ordinary .WAV or .DQA files, or custom user-created .DAT binary files, or even text files. A .DAT file is assumed to be a series of 16-bit signed integer values in 2s-complement binary format. A .TXT (or .CSV) text file is assumed to be a list of signed values in the range of +/-32767; decimal fractions will be rounded to the nearest integer.

Although a special Text File to .DAT option is provided in the File menu to allow conversion of plain text files to the .DAT format, this is not strictly needed for Arb files.

The .WAV or .DQA files may be mono or stereo. If you load a stereo file, it will appear in two adjacent Arb locations. The .WAV files may be either 8-bit or 16-bit. 8-bit files will be converted to 16-bit data internally when loaded.

Regardless of the file extension, Daqarta first looks inside the file for the .WAV header (which is also present in a .DQA file), and if that is not present the file is assumed to be a headerless 16-bit mono .DAT file unless a .TXT or .CSV file extension is found. There is no DAT File Format Dialog to adjust for other formats here, as there is for a normal Open operation, so if you have another file type that is not 16-bit mono you may want to open and re-save it with a .WAV or .DQA format ahead of time, to adjust the format.

Otherwise, you can use whatever file extensions suit your needs. However, note that the file selection dialog will only show .DQA, .WAV, and .DAT files by default, and .TXT and .CSV by selection from the Files of Type control. If you want to see some other type, such as .ABC, enter '*.ABC' in the file name field.

Once the file is loaded, the button will change to show the file name instead of the Arb 0-7 default. The small square button at the right end will change to [X] to allow subsequent removal of that file from the setup.

If you load a stereo file, it will occupy two adjacent buttons. Both will show the same file name, but the small removal buttons at the right ends will show [L] for the upper and [R] for the lower to show that these are Left and Right channels of a stereo pair, and must be removed as a unit.

When you first load an Arb file, the message line on the main Daqarta screen will also show the number of bits, the file type (.DQA, .WAV, or .DAT), and the number of samples. You can view this information for any loaded Arb file by right-clicking on its button. (Right-clicking on an unoccupied button will take you to this Help page.)

Much more detailed file information is available from the File Info dialog ( ALT+F, I), but that only shows the file most recently loaded and will be overwritten by any subsequent file load, whether it is Arb, Play, or a regular data file.

If you save a Daqarta Setup that uses Arb files, the file names and/or paths are included in the setup. If a file resides in Daqarta's own User_Data directory then only the file name is included, since Daqarta always knows how to find the directory. A file that resides in any other directory will have its full path included, which must be no more than 260 characters total.

If you are planning to copy a setup file to another system running Daqarta, you should make sure the Arb files are in User_Data on both systems. If they are anywhere else the full paths may not match between systems, especially on modern systems with paths that typically include a user or system name.

Also, regardless of where the Arb files are, you must make sure you don't delete, move, or rename them. That may be easier to insure if they are in Daqarta's default User_Data directory.

Note that any Arb files that are part of a setup will always be loaded with that setup, even if they are not active in any stream. Thus, if you modify a setup and no longer need an Arb file, removing it will make less demands upon the system.

If you wish to remove a file from a setup that you otherwise want to save, click on the small [X] (or [L] or [R]) button at the right end of the file button. You will be asked to confirm that you want to remove this file from the setup, after which the file button will be restored to its original 'Arb n' state with a blank removal button.

For stereo files, clicking on either the [L] or the [R] buttons will remove both channels together.


Macro Notes:

Use A.L.1.Arb0="MyFile.DQA" to directly load the indicated file as Arb0 for Left Stream 1, and also set that as the Wave type. As long as the file is present and compatible, there will be no user prompts. This will work no matter what dialogs are open.

If you don't use the A. prefix and the Arb dialog is not open, the command will be ignored.

If the Arb dialog is already open, Arb0= without a name will open the File Open dialog showing all .DQA, .WAV, and .DAT files, but with no default name. To specify a default filename, it must be enclosed with quotes.

When there are multiple Arb files loaded, only one may be selected (button depressed) in any given stream. That one will be activated by Wave=Arb for that stream.

Loading a file to a given stream will also select it for that stream. The file will be present in all other streams of both channels, but not selected. To select it for a specific stream, use Arb0=1 to Arb7=1 as needed for that stream.

Use A.L.1.ArbX0= (value ignored) to unload Arb0, if present, from Left Stream 1. There will be no confirmation prompt and the Arb dialog does not need to be open.

If you don't use the A. prefix the Arb dialog must be open, or the command will be ignored. You will be prompted to confirm the removal.


See also Wave Dialog, Arb Wave.

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