Quantum Data 801GC, 801GF, 801GX manual

The upper right corner shows the Pixel Rate. The pixel clock is the master clock used to generate all of the format’s timing information. The pixel clock period is also shown.

The remainder of the top half of the screen is taken up by the horizontal and vertical parameters. These parameters deal with the output signal timing and physical size of the active video area. The names of the parameters are shown at the far left of the screen. The horizontal timing and size parameters are shown in two columns. Most of the information in the left hand column is in machine units and most of infor- mation in the right hand column is in real time units. The only exception is the physical size. You can always enter the size in either inches or millime- ters. The vertical parameters are set up in a similar manner.

❖See a later section in this chapter called “Creat- ing your own format file” for more descriptive information on format parameters and how they relate to each other.

The first line for both sets of parameters is the “Rate.” The horizontal rate is the number of times per sec- ond your display scans in the horizontal direction. The vertical rate is number of times per second your display scans from the top to the bottom of the screen. This rate is equal to the frame rate for non-inter- laced formats and twice the frame or picture refresh rate for interlaced formats.

Entering a new value for the pixel rate, horizontal rate or the vertical rate will cause the other two rates to change. This is because the newly entered rate becomes the reference used to calculate the other two. The ratio of the pixel rate to the horizontal rate will always be equal to the total number of pixels in one horizontal period. The ratio of the horizontal rate to the vertical rate will always be equal to the number of lines in one vertical period for non-inter- laced formats. The ratio will always be equal to one

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