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Arb Files 0-7
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 folder. 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, 8192, or 16384 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 hold a single channel, as a list of signed values in the range of +/-32767; decimal fractions will be rounded to the nearest integer.
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 file type drop-down 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.
As noted, clicking on an unused Arb location will open a File Open dialog to load a file there. However, if you click on an Arb location that is already loaded, that Arb will be selected as the active one for that stream.
If you want to replace a particular Arb, you must first remove it with its [X] button, then click the now-unused location.
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; clicking either button will remove both.
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 folder then only the file name is included, since Daqarta always knows how to find the folder. A file that resides in any other folder 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 folder.
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.
Arb0= without a name will open the File Open dialog showing all .DQA, .WAV, and .DAT files in the User_Data folder. You can click on the file type drop-down control to limit the display to one specific type, or alternatively see .TXT and .CSV text files. The selected file will be loaded to the Arb0 button in the Arb dialogs for all streams, and set as the Wave type for the default Left Stream 0.
L.1.Arb0="MyFile" will open the File Open dialog with the default name set to MyFile. (Note that quotes are needed around all filenames in macros.) If you accept this by hitting Enter or the Open button in that dialog, Daqarta will assume you want to open a file named MyFile.DQA and will fail if that file is not found. If it is found and opened, it will be loaded to Arb0 and set as the Wave type for the specified Left Stream 1.
You can also use "wildcard" names such as Arb0="Data*" to see all files whose name start with "Data", such as "Data001" and "DataFile". You can specify a particular file type such as Arb0="Data*.DQA" or Arb0="*.DQA".
A.L.1.Arb0="MyFile.DQA" will directly load the indicated file as Arb0 and also set that as the Wave type for Left Stream 1. As long as the file is present and compatible, there will be no user prompts. This will work no matter what dialogs are open.
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 will also select it for the specified stream, or Left Stream 0 if none is specified. The file will be present in all other streams of both channels, but not selected. To select a previously-loaded Arb for use by a different stream, use the prefixes for that stream and set the Arb "value" to 1. For example, R.2.Arb0=1 will select a previously-loaded Arb0 file as the Wave type for Right Stream 2.
Unlike manual operation, a macro can directly replace the file at an already-loaded Arb button, without first unloading it. If the file to be loaded is stereo it will require 2 buttons, so you must use the form Arb0#2="MyFile.DQA", where the #2 denotes that it is OK to overwrite the next Arb button with the Right channel.
The file name may be a quoted string as shown above, or it may be a string variable or expression. However, in that case you should always use a #1 or #2 to not only indicate the number of channels, but to also indicate that the left-side variable is a name string and not a value. Examples are A.L.1.Arb0#1=Str0, or A.L.1.Arb0#2=Field1, or A.L.1.Arb0#1=Buf0(a2), or L.1.Arb0#2=Str2 + "*.DQA"
After a load operation Posn?f will be 1 if the user actually loaded a file, or else 0 if the File Open dialog was closed via the Cancel or [X] buttons, or the Escape key. This allows your macro to exit gracefully or take other action.
N=Arb0 will set N to the number of samples in Arb0, or else 0 if it is not loaded. If it is a stereo file, the value is the number of samples in each channel. Note, however, that this approach won't tell you if a file was replaced as discussed above; if the user cancels the File Open dialog, N will show the original size. The Posn?f approach will show 0 if the file was not replaced.
In any of the above macro commands you can either use an explicit button number 0-7 as in the Arb0 examples here, or you can use ArbV to refer to a button specified ahead of time via the Ch Channel Select command.
Use A.ArbX0= (value ignored) to unload Arb0, if present. If it was in use by any stream, that stream's Wave type will be set to Sine. 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.
As with the ArbV command, you can use ArbXV to refer to the Ch variable instead of an explicit button number.
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