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Daqarta for DOS
Data AcQuisition And Real-Time Analysis
Shareware for Legacy Systems

From the Daqarta for DOS Help system:


Color submenu values that control the screen color of the selected upper menu item may be adjusted in two ways:

  • The COLOR number is a value from 0 to 63 that refers to a particular color.
  • The Fine ADJUST values allow control over the mix of the three primary colors (Red, Green, and Blue) that make up the final color referred to by the above color number.


For VGA boards, the fine adjustments allow values from 0 to 63 for each of the 3 primaries, for 262144 different possible colors that could be assigned to any given color number. The color number is thus completely arbitrary. For example, color number 9 normally has [red, green, blue] values of [0, 0, 63], so it is very blue. But these could be adjusted to [63, 0, 0] and the color would be bright red... and in fact identical to the normal color number 36.

When VGA fine adjustments are made, the new primary values become associated with that color number, not the screen item that uses that number. All screen items that use that same color number will thus appear in the same color.

If you attempt to make fine adjustments of the primaries and find that you only get a step size of 21 (and the color number changes as well), that means you are operating in EGA mode instead of VGA mode.

First, be sure that you really have a VGA graphics card in your system. If you are uncertain, check the connector on the back of the card: It should have 3 rows of pin holes. If it only has 2 rows, it is not a VGA card.

If there are two connectors, your monitor must be able to operate while plugged into the one with 3 rows of holes. Some older monitors allow switching between EGA and VGA by means of a switch marked "Analog / TTL"... it must be in the Analog position for VGA.

Another possibility, especially with an early VGA clone card, is that it doesn't support the IBM video detection standards properly. In that case, you can try forcing VGA mode by setting V:v on the INIT line of the DQA.CFG file. This will use the standard (slooowww) VGA BIOS function for palette changes. V:V invokes Daqarta's direct (default) method to eliminate flicker during palette changes, especially on slow systems. No guarantees here!

Note that if you have an EGA monitor connected to a VGA card (via the card's second connector, with two rows of holes), the card may still report your system as VGA. Daqarta will try to update the border or "overscan" area surrounding the main display to match the Panel color. Unfortunately, the EGA display timing isn't really fast enough to support this, so you will probably get a retrace streak near the bottom of the screen. Force EGA mode with V:e to eliminate the border.


Gray-scale summing (SHIFT-G) allows a color VGA monitor to show the view that would be seen with a monochrome VGA monitor. This allows color palettes to be optimized for other systems like monochrome laptops while working on a color system.

The GrayS option is crossed out on EGA systems.


For EGA boards, there are only 64 possible colors, and the relationship between a color and its number is fixed. Thus the fine adjust is interlocked with color number, so in the above VGA example color number 9 would actually change to other numbers as fine adjustments were made, ending at number 36. The smaller number of possible colors is translated into larger steps in the primary values as well... each primary may only have values of 0, 21, 42, or 63.


VGA users may force EGA values by holding down the SHIFT key while making fine adjustments. This allows design of color schemes that will be compatible with EGA systems. Just as for EGA systems, the forced primaries will cause a new color number to be selected that has the matching EGA values. The old color number primaries will be unchanged, even if they were not EGA-compatible due to prior VGA fine adjust.

If you are going to do a lot of this, consider setting V:E on the INIT line of the DQA.CFG file to force EGA mode.


  • A color palette is the set of all screen colors used at one time.
  • Multiple palettes can reside in memory.
  • Select the 'Palette' item from the menu to choose a new palette from memory. Up/Dn cursor keys scroll through palettes.

Whenever a change is made to any color of a current palette, the palette is copied and given the name 'Work'. All further changes are to 'Work', leaving the original unchanged.

After the Work palette is created, it resides in memory with the other palettes, but with a "provisional" status. It is not lost when scrolling to another palette, and can be scrolled back to be modified, but it will be overwritten by modifying any other palette unless it is first saved to memory using the CTRL-PgUp Palette Operations submenu MEM option.


CTRL-PgUp while in a Color menu invokes a special submenu for Palette operations. Move the menu cursor to the desired operation and hit ENTER. The submenu will immediately vanish, and you will be guided by prompts on the message line. You can hit ESC at any time if you change your mind. To exit the submenu without perfoming any of the operations, hit ESC or CTRL-PgUp or CTRL-PgDn.


MEM replaces the current palette with the Work palette, if any, or allows renaming the current palette if not. If the current palette is Work, it will be converted into a regular palette with whatever name you choose.

You will be prompted for a name for the new palette, with the default being the current palette name. So if you want to replace that with the Work palette and keep the same name, you can just hit ENTER at the prompt.

Palette names are strictly for your own reference, and there is nothing to prevent duplicate names. Only the current palette can be replaced, and the prompt is just a way to allow you to rename it. Entering the name of another palette will NOT cause that palette to be replaced instead of the current one... you will just end up with duplicate names.

If the current palette is Work, you should enter a name that will be meaningful to you. Don't accept the 'Work' default name, or that will become its regular selection name. Then the next time you change any palette, another Work will be created that may confuse you.

Palette memory capacity is limited to 23 normal palettes and 13 spectrogram palettes beyond those loaded at startup.


ERASE allows the current palette to be erased from memory. This may be needed to make room for other palettes, or simply to get rid of distractions if you make a lot of trial palettes while searching for one that is optimum for your setup. You will be prompted for confirmation and allowed to ESCape.

You will not be allowed to delete the main Help palette, but you can always replace it. You will likewise not be able to delete the last regular palette in either main or Spectrogram modes.


FILE saves all main or Spectrogram palette memory to disk as a multi-palette file, after prompting for a file name. The default names are SGRAM.PAL and MAIN.PAL, or whatever files were loaded at startup on the third and fourth lines of the DQA.CFG file.

Note that during DDisk recording this option and the LOAD option will not be accessible to prevent drive access conflicts.


LOAD prompts for the name of a multi-palette file to be read into memory, replacing all current main or Spectrogram palettes. The default names are SGRAM.PAL and MAIN.PAL, or whatever files were loaded at startup by the DQA.CFG file.

During DDisk recording this option and the FILE option will not be accessible to prevent drive access conflicts.


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