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slow start graphics on the screen

Using the graph unit (TP5), on some computers it takes always one or two
seconds before the screen has switched to the graphical mode. In the
mean time the program is running and so it happens that the first steps
in constructing an image that has to be build part by part (sometimes
using "delay") have been set before that part of the image appears on
the screen.
What can be the reason of this phenomenon and how can it be avoided?

Herman Serras
Gent (Belgium)

Herman.Ser...@NOSPAMrug.ac.be

 

Re:slow start graphics on the screen


Quote
Herman Serras <Herman.Ser...@rug.ac.be> wrote:
> Using the graph unit (TP5), on some computers it takes always one or two
> seconds before the screen has switched to the graphical mode. In the
> mean time the program is running and so it happens that the first steps
> in constructing an image that has to be build part by part (sometimes
> using "delay") have been set before that part of the image appears on
> the screen.
> What can be the reason of this phenomenon and how can it be avoided?

 Some monitors need to readjust themselves to the new frequencies when
 you switch certain modes. When they do that they turn the image off for
 a sec to prevent damage if the frequencies are out of bounds.
 I think this is what you are seeing. There is not much you can do about
 that except putting in a small delay when switching modes.
Quote
> Herman Serras
> Gent (Belgium)
> Herman.Ser...@NOSPAMrug.ac.be

Re:slow start graphics on the screen


Quote
Herman Serras wrote:
> Using the graph unit (TP5), on some computers it takes always one or two
> seconds before the screen has switched to the graphical mode. In the
> mean time the program is running and so it happens that the first steps
> in constructing an image that has to be build part by part (sometimes
> using "delay") have been set before that part of the image appears on
> the screen.
> What can be the reason of this phenomenon and how can it be avoided?

Happens to me, too. I doubt it can be avoided, it's probably rather a
hardware "problem".

Re:slow start graphics on the screen


Quote
Herman Serras wrote:

> Using the graph unit (TP5), on some computers it takes always one or two
> seconds before the screen has switched to the graphical mode. In the
> mean time the program is running and so it happens that the first steps
> in constructing an image that has to be build part by part (sometimes
> using "delay") have been set before that part of the image appears on
> the screen.

The newer multimode monitors blank the screen for a few seconds
whenever the horizontal or vertical frequency changes. Since the
text mode VGA screen has 400 visible lines, but the graphic mode
VGA has 480 lines, the frequencies change and the monitor blanks
out. You cannot avoid this except with 2 secs of delay before you
start painting.
--
Franz Glaser, Glasau 3, A-4191 Vorderweissenbach Austria ++43-7219-7035
Muehlviertler Elektronik Glaser. Industrial control and instrumentation
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