Daqarta for DOS Contents
Binary data files are used where saved data will be accessed again by Daqarta. This file type includes a header that preserves all major parameter settings. When reading these files, the parameters will be shown in the appropriate menus, just as though PAUSE had been hit right after the data was recorded originally.
When the proper key is hit to request file input or output, a prompt appears on the message line along with a default file name, such as:
Load binary file: C:DATA.000The text input cursor will be positioned at the beginning of the file name. If this is the desired file, ENTER will load it. Otherwise, use the text editor keys to change to the desired file path and name. Since the prompt takes up part of the message line, the editor will restrict text entry to 42 characters for the file specification.
Certain characters are forbidden in DOS filenames, and Daqarta will reject them after ENTER by giving an alert and placing the cursor on the offending character. Forbidden characters are
" + , / ; < = > [ ] |and embedded spaces.
If DOS wildcard characters * or ? are used in the file name, a list of matching files will will pop up in the trace area. Use the normal Right/Left or Up/Down cursor keys to move the highlight to the name desired. The currently highlighted name is also shown as the message line prompt as the highlight is moved. If there are more possible matching files than will fit on one screen (96), use the page keys to see more. HOME and END will take you to the the start or end of the current page, while CTRL-HOME and CTRL-END will move to the start or end of the entire file display.
Any directory entries in the list will be noted with <DIR> after them, including the .. <DIR> entry that indicates the parent of a current subdirectory.
ENTER will cause the highlighted file to be selected. If a directory is selected, all files in that directory will be displayed for further selection (or retreat via .. <DIR>).
If only a path is entered initially, the file display will show all files in the indicated directory as though you had given the path with '*.*' for the file name. If you provide no file name or path (for example, by clearing the default prompt with ALT-DEL), all files for the current directory will be shown.
With any wildcard search, you can use the alphanumeric keys to jump to the "wild" section starting with that character. For a general search, this is similar to the way the Help Index system works: Hit 'A' to see all the entries that start with 'A', and so forth. But what if you had entered 'DATA.*', so that all the entries started with the same letter? When this happens, Daqarta switches strategies and assumes you are interested in the first column that shows a difference. For example, if you had files DATA.000 through DATA.037 and you hit '1', you would see all the files starting from DATA.010 onward.
Hitting ESC during the file list display will return to the prompt line, and hitting ESC from the prompt line will exit the file operation. This allows simple viewing of your files: Hit any file operation key (like I for binary Input), use ALT-DEL to clear the default filename, and hit ENTER to see the files. Hit ESC twice to exit the file operation.
Note that it is perfectly acceptable to navigate the entire drive by selecting appropriate <DIR> and .. <DIR> entries.
If the initial name entry is a specific file without wildcard characters, ENTER will select it directly without further file display. You can use the IncNm option to have Daqarta offer sequential file names automatically.
If the file operation is to write a file, you will be asked to confirm overwriting of any file that already exists.
DATA.000 for OutDt or InDat ARRAY.000 for Memory Array OutDt or InDt. LIST.000 for OutTx SAMPLE.000 for DDisk files SCRN000.BMP for OutSc screen capture.If you access a file of another name, either by entering it at the prompt or scrolling through the file access system, that name becomes the default prompt for the next operation of that type.
If you will be saving many files in succession, however, you have to give each a different name. You can have Daqarta auto-increment the prompted name by activating the IncNm option with the ALT-I key. Under this scheme, only the right-most digits of the name will be incremented, wherever those digits appear in the overall name-plus-extension. (Daqarta versions prior to 1.13 only acted upon the 3-character file extension.)
Typically, you would begin a session by entering a descriptive name for the first 8 characters, plus your desired first extension digits. Then on each subsequent write of that type (DDisk, OutDt, or OutTx), Daqarta will prompt with the next higher extension, as in:
SPEAKER.000 will increment to SPEAKER.001 FRACTURE.001 FRACTURE.002 EABR.N00 EABR.N01
However, if the saved file will be used by other software that expects a certain extension, like .BMP for screen images, you may want to move the active digits to the 8-character portion of the name. Daqarta searches from right to left for digits, and considers the active portion to be all adjacent digits in the right-most group found. These will all be considered free to change as needed. For example:
SCRN1999.BMP will increment to SCRN2000.BMP S2999999.BMP S3000000.BMP SC399ABC.BMP SC400ABC.BMP 99FEB499.BMP 99FEB500.BMP
Besides .BMP screen image files, you may want to use this approach with DDisk files that will later be read as .WAV files by other software.
The period separating the 3-character extension from the 8-character file name will act to end the active portion. For example, in the name 12JUN01.59A only the 59 in the extension is free to change.
When the active portion is in the 8-character part of the file name, IncNm uses only digits 0-9 just like a car's odometer. However, it will not advance beyond the "all nines" state in the right-most group of digits.
Special rules apply when the active portion is in the 3-character file extension. Daqarta will use extensions from 000 to 999, then A00 to A99, and so on up to Z99. Only the most significant digit of the extension rolls through the alphabet.
This scheme was chosen to avoid possible conflicts with file name extensions for unrelated files, since most of those have 3-letter mnemonics like .EXE, .COM, .CFG, .BAT, etc. Daqarta will thus never try one of these names. In the unlikely event that a conflict does arise, you will be required to verify any overwrite, as usual.
Starting with Daqarta version 1.13 you can use IncNm with palette files (which typically use a .PAL extension) for saving and loading series of many different palette files, each of which can hold several different palettes.
The IncNm option, when used with InDat, is also very handy to quickly review the contents of all files in a series... hitting just two keys, 'I' followed by 'ENTER', will bring each successive file (which may itself be an array of traces) onto the screen.
'Hit Y to overwrite C:\DATA\FILENAME.XXX'where the specified path and file will be shown. Hitting any key other than Y (shifted or unshifted) will cancel the file operation.
Only a file that is actually about to be overwritten will cause an overwrite confirmation request, not a file with the same name in a different directory.
For safety, the write confirmation key normally can't be included in a Key Macro. In addition, if write confirmation is needed during a running macro, the macro is immediately exited at that point. This prevents any possibility of a misguided macro trashing your data.
There is one exception to the above rule: If file extension auto-increment (IncNm) is inactive and no changes have been made to the prompted file name, then write confirmation will work with Key Macros. This still protects your data files, except one default file of each type (with .000 extension), or the last file saved.
The purpose of this exception is to allow macros to repeatedly save and read a "scratch" file. A typical use is with a DDisk file where you want to see near-real-time spectrograms with more overlap than can be supported in real-time with any given system speed. You can write a macro that records to a single file, possibly on a RAM drive for speed, then read it back in spectrogram mode with any desired overlap set via the DskRd overlap control. This macro can then be executed repeatedly without filling up your drive with temporary files.
DDisk and OutDt files will be written using the RIFF .WAV format. In addition to the standard header and data areas, the Daqarta format includes a LIST INFO section with all relevant parameters and the 64 character comment line.
The Memory Array file format is equivalent to a concatenation of all the individual files, each with its own .WAV format and LIST INFO section, and all in a single RIFF "wrapper".
DDisk files should be readable by any software that adheres to the RIFF rules for handling file "chunks" it doesn't understand. There is a possible exception to this, however, depending upon the native data format of the board used for acquisition: The standard .WAV file format expects values over 8 bits to be recorded in high-justified two's complement binary format, and those of 8 bits and less as offset binary.
BITS VALUE RANGE ZERO VALUE 8-bit 0 to 255 128 16-bit -32768 to +32767 0 12-bit -32768 to +32752 (by 16s) 0
Makers of sound cards adhere to this convention, but makers of laboratory-grade acquisition boards often don't. Laboratory boards are most commonly 12-bit boards. Some of these are incompatible with the .WAV format because they justify their 12 data bits to the low end of each 16 bit word, so the range runs from -2048 to +2047. Others use offset binary as well, so the value range runs from 0 to 4095 with 2048 representing a zero input.
A stand-alone format conversion utility is planned for use with Daqarta, to allow you to convert DDisk files from boards with these non-compliant data formats into standard .WAV data formats. Although this could have easily been done during DDisk recording via special drivers for those boards that use interupt-driven RTime sampling, this would have slowed the maximum sample rate. Boards that use DMA would have fared even worse.
Memory Array to a file for later recall by InDat. You will be prompted for the file name to save as. You may accept the default with ENTER, or enter another file name directly. You may also use the Daqarta File Access system to navigate your directories if you want to replace a file you have used previously, or just see what else is there. If you enter or select a file name that is already in use, overwrite confirmation will be required.
Separate file name series are maintained for individual or Memory Array files. If you have an individual trace on the screen when you invoke OutDt, the default file name prompt will be DATA.000 or whatever name you last used for an individual trace in the current session. If you have a Memory Array on the screen, however, the default prompt will be ARRAY.000 or whatever array name you last used there. If IncNm is active, each prompt will be one more than its prior value, but the two prompt systems will always be kept separate.
The file will contain all relevant internal parameter settings and any current comment line, and all will be viewable when the file is later read by InData. The file format is a modified form of the standard .WAV format, but don't expect to be able to read it with other programs. A simple waveform may be readable, but waveform averages and simple FFTs use 32 bits per sample and FFT averages use 48... all according to the .WAV standards, but more than most other programs are probably expecting.
If you are saving data after a Joint Average, note that OutDt only saves the currently displayed trace. To save both the waveform and spectrum averages you will need to use OutDt separately for each.
File Access system to replace an existing file or review names. You will be asked for overwrite confirmation of any file that already exists. The trace must be Paused to use this option.
The file will be in plain ASCII text, suitable for use by many other programs. The actual data appears in two columns, with header information lines above so you can identify the data. A typical example is shown below for an FFT average:
TRIG 512 pt PsS Rect Magn Spectrum 32 FFT sweeps Your comment line appears here. kHz mVolt 0.000000 9.798049 0.039062 9.681928 0.078125 10.005226 ... ...
This is a good way to get data into programs that prepare publication-quality charts and graphs, or for any other advanced analysis. Most plotting and analysis programs allow plain ASCII text input, though you may need to provide the program with a "template" or otherwise instruct it as to what to expect.
Some programs evidently assume that you can store all the information you need about your data in the file name, and won't accept the header text (or will make it very difficult). If you must use one of these, first see if it supports some method for automatically deleting the 4 header lines, maybe with a keyboard macro. If not, see if there is some simple way to edit the data from within the program, and delete these lines manually with the program's internal editor. If all else fails, you can always use a separate editor to prepare a copy of the file that has the header lines removed. Be sure you DON'T just remove the header from your original and resave with the same name, or you will no longer have a record of the contents of the file... it will just be two strings of numbers that will be really hard to identify later.
Even if you simply want to print the screen directly, this is often a better option than Print Screen because Windows supports more printers than the GRAPHICS.COM driver used by Print Screen, and you don't have to bother with loading the driver first. In addition, Windows 95 and later systems no longer supply that driver for DOS applications.
The OutSc file save only takes a second or two, compared to the time for printing an entire graphics screen, so you can save many images rapidly during a volatile experiment and print them out later. (Of course, you could also save the data with OutDt and later recall it with InDat for printing.)
As soon as you hit SHIFT-O, the system enters Pause mode if it wasn't there already, "freezing" the screen image to be saved. You will be prompted for a file name for the saved image, starting with SCRN000.BMP as the default. You can accept this default with ENTER, use another name by editing the default name, or use the File Access system to review prior names or overwrite an existing file (with overwrite confirmation).
The standard file name auto-increment system (IncNm) can be used to simplify repeated screen captures. Note that the default filename uses the .BMP extension expected by other programs. IncNm will preserve that part (since it is not numerical) and instead work on the right-most digits of the 8-character portion. You are free to change the base name as desired (IMG00000.BMP, MYTEST00.BMP, etc.).
These .BMP files use no compression (which makes them more widely accepted by other software) and are each 112118 bytes in length. The current color palette is preserved in the file.
File Access system to select an existing file or review names.
You may enter or select either an individual trace file such as DAT.000, or a Memory Array file such as ARRAY.000. Name prompts for each file type are maintained separately, and incremented separately if IncNm is active. Daqarta determines what sort of file to load based upon reading the file itself, not the name. If you intermingle individual and array files within the same name series, like DAT.000 for an individual and DAT.001 for an array, Daqarta will still load them properly, but IncNm operation might get confusing.
After you enter or select the name, the trace will change to show the contents of the file. The Pause option will be highlighted but the Status display will show 'File' instead of 'Pause'. Various readouts and parameter settings will take on the values at the time the file was saved, including the averager sweeps count if the original was an average. The original comment line will be shown. The cursor will be locked out of some control menus to tell you that the values shown are those of the trace data, not those that would be in effect during Live operation. Previous settings will be restored when you go back to Live by toggling Pause off.
If you load a Memory Array file, all of its individual traces must fit into trace memory. You will be asked if you wish to Add to any existing memory traces if there is room, or Replace them with the new array.
The InDat option only applies to files previously saved with the OutDt option, not those saved with DDisk. However, if you try to load a file that Daqarta determines to be a DDisk file, Daqarta will automatically exit InDat and attempt to invoke DskRd instead. Since the DskRd option is only available when Board is inactive (Virtual Source active), you may get the following error message:
'No DskRd from this mode.'
DDisk or OutDt data file and memory trace, and are temporarily installed in the appropriate places in Daqarta when the trace is recalled. Thus the X and Y axes will show the proper scaling, the title will show the channel, number of averager sweeps, and so forth. Other values may be seen by invoking the relevant menu, just as if you were going to adjust that parameter on a Live trace. For example, to see what sample rate was used, invoke the X-axis menu. The cursor will be "locked out" to prevent you from changing these recalled parameters.
Parameters that are set via plug-in modules (those modules that appear in the DQA.CFG file) are not saved in the standard header. Important parameters can be sent to the comment line instead for reference.
The saved parameters include:
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