Contents

Selecting a monitor

Testing your monitor

Advanced controls

Exiting the program

Advanced Monitor Adjustment / Introduction

Advanced Monitor Adjustment / Overview

Horizontal video parameters

Vertical video parameters

Advanced controls / General panel

Non-Interlaced / Interlaced option

Advanced controls / Use Pixel Touch checkbox

Advanced controls / All Pixel Depth checkbox

Advanced controls / Test button


Selecting a monitor

The MGA Monitor Selection utility identifies your monitor to the MGA hardware, and tests the display. Double-click on the MGA Monitor Selection icon in the MGA PowerDesk group Window to start the program. Click on the Monitor Selection button, then highlight your monitor from the list. If your particular monitor is not listed by name, highlight the generic category that it falls into. Click on OK. (You can also delete monitors from the list with the Delete key.)


Testing your monitor

Click on the Test button. The Monitor Test dialog box appears. Using the Resolution and Pixel Depth panels, select the mode that you wish to test. When you click on Test you will see the test screen of a grid and a color spectrum bar. If you want to make monitor timing adjustments and see the results immediately, you will have to run MGA Monitor Selection in Advanced mode. See Advanced controls

The Advanced mode allows you to perform sophisticated high-level signal adjustments that should only be undertaken by experienced technicians. If you proceed with the advanced settings, remember that the `U` key will undo your last adjustment, and that the `Esc` key exits the program.

See Advanced Monitor Adjustment for more details.


Advanced controls

To enable adjustment to your monitor timings you must start the MGA Monitor Selection program with the `/a` parameter. To do this, click once on the MGA Monitor Selection icon and then select File/Properties in Windows Program Manager. In the Command line box type c:\mga\cpanel\mgaset.exe /a and then click on the OK button. The next time you start the application, you will be able to adjust your monitor timing when you click on the Test button. To interactively adjust your monitor, click on the Test button in the Monitor Test dialog box. You will see the test screen with the a panel of adjustment controls floating on top (you can reposition the panel).

The controls for adjusting your monitor are explained below. Note that in some cases excessive adjustment may cause the display to turn completely black. Don't be alarmed - simply press `U` to undo the last change or `Esc` to exit the dialog box:

Pixel Clock	This adjustment is a means of simultaneously adjusting both the horizontal and vertical frequencies of the MGA board to provide the optimal display for your individual monitor. These are quite subtle corrections that are required for only the most exacting standards. Your best bet is to avoid using this function unless you are completely familiar with video parameter programming. The horizontal and vertical frequencies that result from the Pixel Clock adjustments are displayed in the Frequency panel at the bottom of the dialog box.

Size	These four arrows let you resize the raster image both horizontally and vertically for this particular display mode. When the arrow turns from blue to black, you can no longer continue the adjustment in that direction.

Move	These four arrows allow you to move the entire raster image left, right, up, or down for this particular display mode. When the arrow turns from blue to black, you may no longer continue the adjustment in that direction.

Keys	The `Z` key toggles through zoomed displays (2x, 4x, 1x) of the same mode. Note that in some cases excessive adjustment may cause the display to turn completely black. Don`t be alarmed - simply use one of the following two keys to remedy the situation:

U:	This key undoes the last adjustment

Esc:	This key exits the adjustment dialog box

If you press Esc to exit from a blacked-out screen, be sure to not save the changes when you exit the program. See Also: Exiting the program.

Frequency	The horizontal and vertical frequencies that result from the Pixel Clock adjustments are displayed in the text boxes at the bottom of this panel. Refer to your monitor's instruction manual to determine the frequency ranges that are supported by your monitor.


Exiting the program

The structure of the program allows you to change your mind at every turn, so if you accidentally follow the wrong path, you can still correct the situation by carefully following the screen prompts. To navigate through the two most common scenarios, consult the following instructions:

·   I have made an adjustment that I'm happy with, and I wish to save it.

1. Press the Esc key.

2. Click on Save.

3. In the Monitor Name dialog box, click on OK to permit the current monitor data to be overwritten, or provide a new name, then click on OK. If you retained the original monitor name, you'll be prompted before the monitor data is altered.

4. In the MGA Monitor Selection dialog box, click on the Save and Exit button.

·   I don't like the adjustment I made. I want to exit without harming my current setup.

1. Press the Esc key.

2. Click on Close.

3. Click on the No button in the message box that states The video parameters have changed. Do you want to save them?.

4. In the MGA Monitor Selection dialog box, click on the Cancel button.


Advanced monitor adjustment / Introduction

Advanced signal adjustments should only be undertaken by experienced technicians. If you proceed with the advanced settings, remember that the `U` key will undo your last adjustment, and that the `Esc` key exits.

The Advanced Monitor Test dialog box contains edit boxes in which you may input precise video parameter information to be relayed to your monitor from the MGA board. Refer to your monitors specification sheet or users manual for the range of values that are supported by your monitor.

Before you begin to fine tune the monitor signals that are generated by your MGA board, you should first ensure that your monitors built-in controls are set properly, and that they produce an acceptable display.

See Also:	Advanced Monitor Adjustment / Overview

Horizontal video parameters

Vertical video parameters

Advanced controls / General panel

Advanced controls / Use Pixel Touch checkbox

Advanced controls / All Pixel Depth checkbox

Advanced controls / Test button


Advanced Monitor Adjustment / Overview

The signals that are generated by your MGA board control many aspects of your monitors display. Internally, the MGAs frame buffer is configured for certain display modes by our software, and the pixels that originate from the frame buffer are organized by the MGA and monitor hardware as raster lines on your screen.

The horizontal and vertical sync signals from the MGA board control your monitor`s raster scan circuits. These sync signals create a timing framework within which the display information is generated on a frame-by-frame basis.


Horizontal video parameters

The horizontal frequency, or `line rate`, represents the number of lines that can be drawn per second. The relationships between the horizontal video parameters and the signals used to generate the video are shown in the following illustration (not to scale):

The `sawtooth` pattern represents the voltages that control the horizontal movement of the monitors guns as they travel across the screen.


Vertical video parameters

The relationships between the vertical video parameters and the signals used to generate the video are shown in the following illustration (not to scale):

The vertical frequency, or `frame rate`, represents the number of frames that can be drawn per second.

The most flexible method of adjusting the size and aspect ratio of the raster is to alter the blanking intervals. The Monitor Selection program gives you the ability to adjust the blank by adjusting its individual components, which are the Front and Back Porch and the Sync. You can also make adjustments to the horizontal frequency and pixel clock parameters.


Advanced controls / General panel

To understand how the pixel clock affects the display, you should understand that the MGA board generates this clock pulse as a timing signal. Even though part of the signal is devoted to pixel display and part is devoted to sync and blank, the pixel clock is still running throughout. You might imagine that imaginary pixels are still being sent even when no display occurs. A display of 1024 pixels includes the time it takes to output 1,024 displayed pixels (the display time) as well as to output several hundred other (blanking time) pixels. Therefore, adjustments to the pixel clock also serve to alter the blanking intervals.

Non-Interlaced / Interlaced option

Most modern monitors offer non-interlaced displays. In this case, the default setting should not be changed. However, if your monitor is interlaced, you can click on the Interlaced option button to reconfigure the display.


Advanced controls / Use Pixel Touch checkbox

When you use the Pixel Touch zoom feature of the MGA Control Panel, the horizontal sync value must be a multiple of 32 in order for the zooming to occur. When you enable the Use Pixel Touch check box, the horizontal sync values will increment 32 pixels at a time when you use the H. Sync scroll arrows. When the Pixel Touch zoom is not being used, the horizontal sync increments in multiples of 8 pixels when you use the H. Sync scroll arrows.


Advanced controls / All Pixel Depth checkbox

The All Pixel Depths box serves a dual purpose:

1. Before you modify anything, if the box is checked, this indicates that the timing you are about to edit is being used for all the pixel depths at this resolution. When you start to change timing values the check box will become cleared, to indicate that this new timing will not apply to all pixel depths.

2. If the check box is cleared, you can impose this timing on all pixel depths by clicking in the box. You will see a warning message telling you that all other pixel depths for this resolution will be set to these timing values.


Advanced controls / Test/Adjust button
Advanced controls / Test button

When you press the Test button, the monitor adjustment controls are available. In addition, you will see readout panels that show the precise numerical values for the timing parameters as you adjust them.

The following controls function in the same way as previously described:

·Pixel Clock	·Size

·Move	·Keys

The Horizontal panel displays the current values of:

·Horizontal frequency	·Front Porch

·Horizontal Syncronization	·Back Porch

The Vertical panel displays the current values of:

·Vertical frequency	·Front Porch

·Vertical Sync	·Back Porch

Pixel Clock/MHz:	Displays the current pixel clock value.

Zoom Factor:	Displays the current zoom level (1x (the normal view), 2x, or 4x).